9th IAA PLANETARY DEFENSE CONFERENCE 2025

After the success of the NASA/DART mission (Daly et al., 2023; Chabot et al., 2024), attention has turned to demonstrating alternative technologies for mitigation and deflection. The gravity tractor is one such technology that uses its own gravity to slowly ``tow'' an asteroid and alter its trajectory (Lu and Love, 2005). Using the Gauss planetary equations, we derive a simple first-order...

See attached abstract

Ground-based asteroid surveys have excelled at finding new near-Earth objects (NEOs) over the last three decades. However, the characterization of those bodies often lags due to the increased observation time needed to determine physical properties. With the Vera Rubin Observatory coming online later this year, this problem will only become more apparent. We present a newly funded NASA PDCO...

Thousands of Near Earth Objects (NEOs) are discovered every year, but only a small number of these have their compositions determined. In fall, 2024, we have begun a new program to determine the rough taxonomies and therefore compositions of at least ~1000 very small (absolute magnitude >25, or diameters <30 meters) NEOs over a three year period using the MuSCAT3/4 simultaneous four-channel...

As the threat of hazardous Near-Earth Objects (NEOs) continues to pose a potential risk to Earth’s safety, developing effective planetary defense strategies is becoming an urgent priority. One promising approach is the use of a nuclear deflection mission, leveraging the energy released by a nuclear device to alter the trajectory of an incoming NEO. This abstract outlines the key technologies...

In recent years, eleven small near-Earth asteroids were discovered a few hours before colliding with Earth. They were all about one meter in diameter and they all disintegrated in the atmosphere, generating bright fireballs without causing damage. In some cases – namely 2008 TC3, 2018 LA, 2023 CX1, and 2024 BX1 – several meteorites have been recovered. In cases like these, it is not always...

PDF of abstract included as attachment.

Planetary defense (PD) scenarios present unique mission design challenges compared to typical interplanetary missions. Critically, the target body cannot be selected to conform to predefined science or technology demonstration objectives. Instead, cosmic chance dictates the impending Earth...

Abstract
Keywords: Space debris, Near Earth Orbit, Terminal rocket stage, Mitigation, Hazardous.
Terminal stage in Launch vehicle poses several challenges: space debris, residual propellant and high-pressure gases. Space debris is due to spent terminal rocket stage, explosion or fragmentation of damaged space objects. The increasing space debris leads the risk of collisions with...

As Near-Earth Objects (NEOs) continue to present significant risks to planetary safety, advancing asteroid deflection technologies is crucial for strengthening global defense strategies. Traditional methods, such as kinetic impactors and gravity tractors, have demonstrated potential but face challenges related to scalability, precision, and lead-time adaptation. This study introduces an...

The International Asteroid Warning Network (IAWN) is an organized network established in 2013 and sanctioned by the United Nations to coordinate worldwide entities involved in the detection, tracking, and characterization of Near-Earth Objects (NEOs). IAWN provides means of communicating and developing plans and protocols for responding to impact threats by obtaining and processing...

The OSIRIS-REx and Hayabusa2 missions yielded a wealth of data that is transforming the understanding of rubble-pile asteroids, providing unprecedented insights into their composition, structure, and evolution. Rubble-pile asteroids are highly porous, loosely bound collections of rocks and boulders held together primarily by gravity, with minimal cohesion, and measuring less than a few...

The planetary defense community practices mission-planning to deflect or disrupt any near earth asteroids (NEAs) that are found to be on an Earth-impacting trajectory. Many scenarios must be con- sidered to determine the optimal mission type to recommend. While a kinetic impactor is the first choice for a deflection mission, either a large asteroid or a short warning time may require using a...

Coordinated use of modeling and in-situ radar data can advance our understanding of the internal structure of rubble pile asteroids, essential for planetary defense and planetary science. On April 13, 2029, asteroid 99942 Apophis will pass within 32,000 km of Earth, closer than geostationary orbit. A potential Caltech-led mission could escort Apophis through this encounter, observe its...

The close Earth approach of the Apophis is the first event in which 300 m size asteroid flybys with the altitude lower than GEO ring and the exciting event for mankind. The year 2029 in which the close flyby occurs is designated as “International Year of Asteroid Awareness and Planetary Defence” by the United Nation. Since the flyby occurs only 4 years later, the development of a new...

ASSESSING THE VULNERABILITIES OF THE MEERKAT ASTEROID GUARD

C. Drury (a), M. Frühauf (b) , J.L. Cano (c) , F. Gianotto (a), M. Fenucci (a), L. Faggioli (a)

(a) ESA ESRIN / PDO / NEO Coordination Centre, Via Galileo Galilei, 1, 00044 Frascati (RM), Italy
(b) Technical University of Munich, Lunar and Planetary Exploration, Lise-Meitner-Str. 9, Ottobrunn, 85521, Germany
(c) ESA ESOC /...

The physical and chemical composition of asteroids plays a pivotal role in determining the efficacy of planetary defense strategies. Asteroids are classified into three primary types: metallic (M-type), carbonaceous (C-type), and stony (S-type). Each composition presents unique challenges and opportunities for mitigation techniques, such as kinetic impactors, nuclear disruption, and gravity...

Asteroids show significant variation in the polarisation properties of their reflected light, which are diagnostic of their surface mineralogy, geometric albedo, and texture. These properties have historically been used to characterise them; however, this remains an under-explored method for their taxonomic classification. Potentially Hazardous Asteroids (PHAs) form a particularly important...

(469219) Kamo`oalewa is a small near-Earth asteroid, which is currently a quasi-satellite of Earth. Lightcurve measurements revealed a rotation period of about 30 minutes, while the spectrum is compatible with that of S-type asteroids. This object has been selected as the target of the sample-return Tianwen-2 mission of the China National Space Administration.

In early 2024, we performed...

In this work, we present the first results of the ATLAS (Asteroid Terrestrial-impact Last Alert System) unit that will be installed by the Instituto de Astrofísica de Canarias (IAC) at Teide Observatory (TO) on Tenerife Island, Spain, in January 2025. The ATLAS-Teide unit will operate as part of the ATLAS network (https://atlas.fallingstar.com/) under an agreement between the IAC and the ATLAS...

Low-thrust, long-period asteroid deflection strategies have become a primary focus in planetary defense research. In such strategies, autonomous cooperative navigation for multi-spacecraft landing has been recognized as one of the critical technologies to achieve precise spacecraft deployment on the asteroid surface. However, existing spacecraft autonomous navigation methods based on...

The concept of a ≈10 kg “nanolander” equipped with a customized suite of instruments designed to complement its carrier spacecraft’s science has been proven valuable e.g. with the Mobile Asteroid Surface sCOuT (MASCOT) surface science package on JAXA’s Hayabusa2 mission. MASCOT successfully landed and operated on (162173) Ryugu on October 3rd, 2018, bridging the gap between the results of...

6ROADS, an independent company, owns a global network of fourteen remote telescopes strategically located across six continents. The primary mission focuses on tracking and surveying man-made objects in Low Earth Orbit (LEO), Medium Earth Orbit (MEO), and Geostationary Orbit (GEO), as well as confirming newly discovered Near-Earth Objects (NEOs) approaching Earth’s vicinity. The backbone of...

Keywords: Binary Asteroid Formation, Collisional Spin-Up, N-body simulation
The evolution of rotation rates of small asteroids is subject to mechanisms including: (1) the Yarkovsky-O’Keefe-Radzievskii-Paddack (YORP) effect resulting in a net torque that can secularly modify the body’s rotation rate and orientation; (2) off-spin-axis collisions by projectiles can change the spin state of an...

Reconnaissance missions are a crucial next step when a celestial body threat to our planet has been identified and confirmed to be significant. This helps in studying the body in detail by determining precise orbital characteristics and mapping the physical specifications, thus enabling the all the stakeholders to determine the best possible course of action along with the timelines. Multiple...

With its extremely large field of view of ≃47 square degrees, which scans the entire northern sky every two nights, the Zwicky Transient Facility (ZTF) is a powerful tool for serendipitous detections of near-Earth asteroids (NEAs). This effort aims to both discover new NEAs and refine the orbital information of known objects, anticipating and mitigating future dangerous collisions. We present...

The European Space Agency’s (ESA) Flyeye telescopes will play a crucial role in global planetary
defense efforts, with their unique optical design inspired by the compound eyes of a fly. These telescopes
feature an expanded field of view, allowing a more efficient survey of the sky and improving the
detection of potentially hazardous Near-Earth Objects (NEOs).
We present the status of the...

Keywords: Apophis, OSIRIS-APEX

The OSIRIS-APEX mission will repurpose the OSIRIS-REx spacecraft to study Apophis, rendezvousing shortly after the asteroid’s close approach to Earth on 13 April 2029 [1-3]. The mission will produce and release many data products. We highlight here some that will be of particular interest to the planetary defense community.

• Shape model: We expect to...

The paper proposes an approach to designing transfer trajectories of a spacecraft from its initial orbit in the vicinity of the Sun-Earth libration point to near-Earth asteroids. The features of motion in bounded orbits around libration points, as well as invariant manifolds associated with them, open up the possibility of redirecting a spacecraft to trajectories of rendezvous with near-Earth...

Asteroid spacecraft have significant potential in the field of planetary defense, particularly in preventing or mitigating the threat posed by near-Earth objects (NEOs). These objects, which include asteroids and comets, are classified as potentially hazardous if their orbits bring them into close proximity with Earth. While the likelihood of a catastrophic impact is low, the consequences of...

In 2019, the Catalina Sky Survey invited SPACEWATCH® to collaborate with them and the University of Minnesota on a new survey for near-Earth objects (NEOs) using Steward Observatory’s Bok 2.3-m telescope on Kitt Peak in Arizona to discover faint near-Earth asteroids and to search for Earth Trojans. We propose for 6 to 9 nights of dark/grey time each lunation for the new Bok NEO Survey which...

Introduction: After the successful launch of the ESA/HERA mission [1] on 7 October 2024 it is timely to recall what we have learned from The NASA Double Asteroid Redirection Test (DART) impact [2] and ASI/Light Italian Cubesat for Imaging of Asteroids (LICIACube) [3] mission. DART was the first space mission that successfully demonstrated the kinetic impactor technique for planetary...

Planetary defense represents a unique socio-ethical and legal challenge being simultaneously everyone’s responsibility and no one’s. A robust planetary defense strategy depends not only on developing technological capabilities but balancing regional and global political interests and creating a “mandate to act” in the case of an impact hazard. Planetary defense activities have the potential to...

Asteroid search is a global effort for planetary defense. The International Astronomical Search Collaboration (IASC) is the leading global educational outreach program that provides astronomical datasets to citizen scientists to help asteroids discovery worldwide. Since 2021, the Ivorian Astronomy Association is involved in asteroid search endeavors. Two asteroids (2022 SW188 and 2023 TR26)...

Near-Earth objects provide a considerable risk to mankind. To comprehend the issue and safeguard our planet, it is essential to monitor and advance technologies to alleviate the risk. NEOs are mineral-rich and potentially provide fresh resources for future space research missions. Monitoring Near-Earth Objects (NEOs) may enhance our understanding of solar system origin as well.
By analyzing...

This proposed Research article focuses on planning a map for “Economically Feasible” merged method for swift growth in sector of “Asteroid Mining” for metal and mineral’s mining from Outer Space. The most focused point is “Identification of Exploration of Rare Earth” metals and minerals to be identified and processed.

Scientific Rationale of this Proposed Concept is conception of Air...

Keywords: Planetary Defense Ethics, Extramilitary Domain

Age-old concepts of sovereign military power have traditionally transferred into new physical and technological domains (e.g., air, undersea, electromagnetic spectrum) to create security. However, some recent emerging threat domains have been excluded from nations’ military responsibility. Two current examples are cyber security and...

Please see attached PDF.

The hypothetical asteroid threat exercise for the 2025 planetary defense conference includes an intriguing trajectory design challenge for possible deflection missions. The long (17 years) time span between the impact threat announcement and the possible impact date allows one to exploit multiple gravity assist (MGA) trajectories involving the inner solar system planets to allow an otherwise...

Keywords: Dimorphos, Apophis, HERA, RAMSES

CNES contributes to the most essential Planetary Missions of this decade, aimed to the binary asteroid (65803) Didymos, and to the asteroid (99942) Apophis. We start with the Hera mission launched by ESA on October 7th 2024. Its target, Dimorphos, the 151 meters moon of Didymos, was successfully impacted by NASA's DART proe on September 26th 2022....

The damage from asteroid impacts is often measured in terms of areal extent and affected populations from the initial effects from blast waves, non-ionizing thermal radiation, and tsunamis (if the impact is over an ocean) [1-4]. We have considered the potential for additional effects, which could extend both to geographic areas affected and prolong risk to additional populations [5]. In...

The European spacecraft mission HERA is currently flying towards the binary asteroid system Didymos. The spacecraft will arrive in the vicinity of the asteroids at the end of 2026 and thanks to its autonomous vision-based GNC, will be able to fly autonomously down to a distance of a few hundred meters from them. The main purpose of the mission is to characterize the impact of DART (NASA...

Near Earth Objects (NEOs), such as asteroids on an Earth-impact trajectory, are low probability, high consequence natural hazards. To understand the consequences of Earth-impacting NEOs we rely on numerical simulations to model potential damage. In this study we investigate asteroid ocean impacts, focusing on the primary and secondary hazards such as tsunami wave generation and atmospheric...

Keywords: Asteroid Deflection, Asteroid Disruption, Nuclear Mitigation Strategy, Asteroid Composition, Near-Earth Object

Session: Deflection/Disruption Modeling and Testing

Space is perpetually monitored by scientists for near-Earth objects (NEOs) that could potentially collide with Earth. If a problematic NEO is detected early enough, then multiple mitigation options can be devised. One...

The PI method represents an alternative approach to planetary defense from asteroids which utilizes energy transfer to disrupt an asteroid rather than momentum transfer to alter its orbit. The method makes use of various possible configurations of hypervelocity penetrators which can operate in one of six modes, ranging from asymmetrical fragmentation for enhanced deflection (which is useful...

Near-Earth Objects (NEOs) represent a potential hazard to Earth, and effective planetary defense strategies are crucial for mitigating these risks. The Klet Observatory in the Czech Republic plays a pivotal role in both the research and public outreach related to NEOs. Since its establishment as an astrometric NEO follow-up station in 1992, and more recently with the deployment of the 1.06-m...

In this work, we apply jet transport techniques as implemented in the open-source software package NEOs.jl [1, 2] to the problem of orbit determination and impact probability predictions for asteroid 2024 PDC25, the hypothetical scenario for the 9th Planetary Defense Conference 2025. From the astrometry file available for 2024 PDC25 at Epoch 1 [3], we perform a preliminary orbit determination...

This study examines whether the Kinetic Impactor, Nuclear Explosion or Laser Ablation could mitigate the impact threat of asteroid 2024 PDC25, a hypothetical asteroid with 17 years warning created for the 2025 IAA Planetary Defense Conference exercise. The potential impact date of asteroid 2024 PDC25 is April 24, 2041. Its absolute magnitude is estimated to be H = 21.9 ± 0.3 and the size...

Keywords: Planetary Defense, Post-SDGs, fundamental connection, the Year 2025, Apophis,

The Sustainable Development Goals (SDGs), adopted unanimously by United Nations member states at the General Assembly in September 2015, represent a set of international goals aimed at creating a sustainable and better world by 2030. Considering the significance of the SDGs, several space-related...

The IRAC camera on the Spitzer Space Telescope observed 2175 Near Earth Objects (NEOs) during its Warm Mission phase, across three large surveys and a small number of dedicated small projects. We present the final reprocessing of the NEO data and infrared photometry in the 3.6 μ and 4.5 μ regimes [1]. The window of observation has allowed for a small number of complete light curves to be...

Asteroids with sizes below a few km are mostly believed to be loose aggregates bound together primarily by self-gravity, known as rubble-piles. Historically, rubble-pile asteroids have been treated as essentially cohesionless aggregates. Recent evidence from high-resolution spacecraft in-situ observations (e.g. Hayabusa2 and OSIRIS-REx missions) show very low values for cohesion on the surface...

Solar System objects impact Earth’s atmosphere daily, but their small size makes them undetectable before atmospheric entry. To better understand these impactors, we need multi-instrument observations of their disintegration phase [1].
In this study we explore several methods of measuring the pre-atmospheric mass of meteoroids with well-known trajectory, at the source of ton TNT-scale...

Recent events and research have uncovered an additional potential contributor to global risk estimates from airburst and impact events, the Lamb-wave driven global tsunamis. The 2022 explosion of Hunga Tonga–Hunga Haʻapai (HTHH) generated a global Lamb wave that created tsunami waves in the oceans around the world where the water depth provided the conditions needed to create a Proudman...

At the time of writing this abstract, eleven asteroids had been discovered in the sky prior to their impact on Earth. The first one was detected in 2008, but in 2024 alone, four were discovered. This shows that the number of detection is steadily increasing, and we should expect this trend to continue in the coming years with the ongoing improvement of observational techniques and the...

This LOSSOL presentation will focus on current developments in high energy laser technology, merits and challenges, and Planetary Defense application of Directed Energy Systems for timely intervention of bolides threat to high value assets on the Moon and potential for Earh applications as well.

We are part of an expertise group of over two dozen astronomers, computer scientists, data scientists and digital Big Data research platform experts at 11 universities and research institutes in South Africa and Europe. We study Near-Earth Objects (NEOs) for Planetary Defence and scientific purposes.

NEO Discovery. In this talk, we present our programme and results for algorithms and...

The near-Earth binary asteroid (65803) Didymos gained significant scientific attention after the successful impact of NASA's DART mission on its secondary, Dimorphos, validating kinetic impact as a planetary defence strategy (Thomas et al., 2023). This study builds on previous analyses of particle dynamics on Didymos' surface (Trogolo et al.,2023). Using updated physical parameters (Naidu et...

Rapid reconnaissance flyby missions are the fastest means of obtaining asteroid characterization data in a planetary defense scenario. However, the small masses of potentially hazardous asteroids (PHAs) require unreasonably or impossibly close flyby distances to achieve useful mass measurements with ground-based tracking, the current state of practice. This capability gap limits the value of...

Measuring Asteroid Distances from a Single Observatory in One Night with Upcoming All-Sky Telescopes

The successful demonstration of NASA DART mission success in testing the kinetic impact as a planetary defense technique will be enhanced even more by the scientific observations of the upcoming ESA Hera mission. The spacecraft, launched on October 2024, and now on his way to the Didymos-Dimorphos binary asteroid system, will understand in detail the effect of the DART impact and the outcome...

Near-earth objects can range from less than one meter to tens of kilometres. While smaller NEOs explode entering the atmosphere, those bigger than 140 m are considered potential hazardous objects (PHO) and are monitored to avoid future catastrophes. Even though early detection and warning systems help us in analysing the threat, we need technology to deflect or destroy the PHOs before they...

Please see attached PDF.

Acknowledgement
Funded by the European Union (ERC, TRACES, 101077758). Views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the European Union or the European Research Council. Neither the European Union nor the granting authority can be held responsible for them.

(See attached file for formatted layout and figures.)

We developed asteroid rubble pile simulations made of crushed basalt. Within the DART community, nearly all computations were performed with basalt as a surrogate for the Dimorphos surface material since it is viewed by many as an appropriate analog to the asteroid material. Basalt was also used by DART Investigation Team members and...

Abstract: Since 1960 TLS (IAU code 033)
has operated the largest imaging Schmidt telescope
with a correction plate of 1.34 m in diameter. Initial
asteroid work by Freimut Börngen aimed at discover-
ing main-belt asteroids. In 2010, it was resumed by
joining the worldwide NEOCP effort. TLS became a
sensor in ESA’s NEOCC program in 2019. It is now
one of the major European observatories...

The South African Astronomical Observatory (SAAO) has made significant contributions to the observation and characterisation of near-Earth asteroids (NEAs), supporting global planetary defense efforts. Located near the town of Sutherland in the Northern Cape, SAAO's diverse array of telescopes, ranging from 10-m to 1-m in diameter, offers capabilities in spectroscopy, multi-filter photometry,...

The analysis of mm-wavelength thermal emission from near-Earth asteroids can be used to constrain thermophysical (thermal inertia, emissivity) and radiative (index of refraction, loss tangent) properties of the top few centimeters of regolith. These properties can be used to constrain the regolith porosity. For near-Earth asteroids (NEAs), regolith porosity is one of the physical properties...

Asteroids are key to unlocking the secrets of our solar system's formation and evolution, as well as assessing potential threats to Earth from impacts. This paper presents a thorough account of a significant asteroid search campaign conducted as part of an international collaborative initiative focused on identifying and tracking near-Earth objects (NEOs) and main belt asteroids...

Keywords: near-Earth object, planetary defense, survey, infrared, detect

The Near-Earth Object (NEO) Surveyor mission is a key element in our future planetary defense portfolio, which will provide a complete survey of our solar system in the infrared.

The mission is designed to detect, track, and characterize small bodies throughout our solar system.
By congressional mandate, NASA must...

Near-earth objects pose a significant threat to humanity, potentially impacting a profound disruption beyond our imagination. Like volcanoes, NEO also played a significant role in shaping the surface of our planet. Whether they explode above the ground or reach the surface, NEO impacts have done significant damage. In 2013, an asteroid about 18 m in diameter called Chelyabinsk exploded while...

This work presents the results of an observation campaign conducted in the second half of 2024 and which will last until the first half of 2025, aimed at the photometric characterization in the BVRcIc bands of the brightest near-Earth asteroids observable from the northern hemisphere.
The observations were mainly conducted using the “G.D. Cassini” 1.52-m F/4.8 Ritchey-Chrétien telescope of...

In this study, we propose the method of frame stacking which is implemented in celestial (equatorial) coordinate system. This method allows to prolong the “effective exposure time” of near-Earth objects (NEOs) increasing the efficiency of capturing faint objects. Additionally, it can be realized using CCD frames obtained by several optical systems simultaneously or at different...

The Kalkkop Crater, located in the Eastern Cape, South Africa, is a deeply eroded small impact structure that was filled with lake sediments following the impact event and formed at approximately 250 ka [1]. The crater was initially drilled for petrophysical studies [2], then later re-investigated to confirm the impact hypothesis [3]. The crater was assumed to have a simple crater morphology,...

Keywords: NEO, Detection, New Programs,

Near-Earth Objects (NEOs) pose a significant threat to Earth. The Chelyabinsk meteor impact in 2013 served as a stark reminder of this danger, releasing energy equivalent to 30 times the Hiroshima atomic bomb, causing widespread infrastructure damage and injuring approximately 1600 individuals. Apophis, is an asteroid approximately 370 meters in...

A nuclear electric propulsion (NEP) vehicle concept and mission were developed for the 2025 Planetary Defense Conference (PDC) asteroid target. The work builds upon recent work by Brophy, et. al. using solar electric propulsion for planetary defense. The results with NEP are different given that the NEP vehicle’s power is not affected by distance from the sun. A relatively near-term NEP...

In this paper, I argue for a new perspective on the design of nuclear weapons for planetary defense missions. At the time of writing, the mandate for Sandia’s planetary defense team is to modify existing stockpile weapons as needed for employment in the deflection of a near-earth object. However, this runs up against a universally acknowledged but seldom-mentioned problem: the placement of...

Keywords: NEOs, NEAs, Near Earth Space

Decameter size NEAs are of particular interest in the context of the NEO problem because the frequency of collisions with such bodies is much higher than that of larger bodies and the consequences of collisions can be still significant. So far, the population of decameter bodies has been poorly studied since they are difficult to observe. To build an...

On September 26, 2022, the DART spacecraft collided with the 160-meter asteroid Dimorphos and shifted its orbital period relative to its 700-meter companion asteroid Didymos by approximately 33 minutes. The Double Asteroid Redirection Test (DART) successfully demonstrated deflection of an asteroid by a high-speed kinetic impactor and enabled in-depth analysis of the experimental results.
The...

The European Space Agency (ESA)’s Lunar Meteoroid Impact Observer (LUMIO) mission represents a cutting-edge advancement in understanding the meteoroid environment around the Earth-Moon system. Lead by Politecnico di Milano (PoliMi) and supported by the Italian Space Agency (ASI), the Norwegian Space Agency (NOSA), United Kingdom Space Agency (UKSA), and Swedish National Space Agency (SNSA),...

In asteroid kinetic deflection missions, the presence of ejecta leads to a phenomenon where the system's momentum appears to be "amplified" after impact. In our previous work, we leveraged this phenomenon and demonstrated, through simulations of kinetic deflection missions to 32 potentially hazardous asteroids (PHAs), that striking a point offset from the geometric center of the asteroid...

The Planetary Science Team at the University of Alicante (Spain) is currently formed by 10 researchers dedicated to modeling and physical characterization of small bodies in the Solar System. Here are some current topics:

\textbf{IEO Survey}: Currently, 34 objects have an Interior Earth Orbit (IEO) that don't pose an immediate risk but may eventually lead to Earth-crossing trajectories due...

The OSIRIS-APEX (Origins, Spectral Interpretation, Resource Identification, and Security–Apophis Explorer) mission will approach and rendezvous with asteroid (99942) Apophis in the spring of 2029, just after its close approach to Earth (DellaGiustina et al., 2023). APEX has three primary mission goals. The first is to study the processes that drive the evolution of small asteroids, including...

Introduction: Asteroid impacts can cause varying levels of damage across different areas, largely depending on the energy of the impactor. The complex processes that cause damage are not limited to the initial effects. First-order effects (those that are triggered directly) such as blast waves, craters, ejecta plumes, seismic activity, and thermal radiation have been the primary focus areas of...

The Taurid Complex is a large interplanetary system that contains comet 2P/Encke, several meteoroid streams, and possibly a number of near-Earth asteroids [1]. The size and nature of the system have led to the speculation that it was formed through a large-scale cometary breakup [2]. Numerical investigations and meteor observations have suggested that planetary dynamics can create a resonant...

The Chelyabinsk meteor entered Earth’s atmosphere on 15 February 2013, producing a shock wave that injured about 1,500 people and damaged thousands of buildings. Despite its relatively large size (~20 m), the progenitor asteroid approached Earth undetected. Its radiant was too close to the Sun for standard near-Earth asteroid (NEA) search programmes. In addition, it was very faint due to the...

Near-Earth asteroids (NEAs) provide valuable opportunities to study the physical and structural properties of small bodies. While most asteroids have rotation periods longer than the "cohesionless spin barrier"—a 2.2-hour limit beyond which rubble-pile asteroids would break apart due to centrifugal forces—some rotate much faster, challenging current understanding of the internal structure of...

Keywords: kinetic impactor, asteroid deflection, asteroid disruption

The potential for accidental disruption of an asteroid during a kinetic impact deflection attempt poses significant risks for planetary defense strategies. As the velocity change applied to an asteroid during a deflection attempt increases, so does the likelihood of inadvertent fragmentation or partial disruption....

In the event of a potential asteroid impact on Earth, if an attempt can be made to prevent it, time will be of the essence. Simple models for determining what mission types are best-suited to deploy based on the circumstances are invaluable tools for facilitating a swift response. When NASA mission designers are exploring the mission space and uncertainties for exercises, such as the one...

Asteroids with MOID less than 1 AU are of significant scientific interest due to their potential for close approaches to Earth's orbit. Characterizing their physical properties—size, shape, and spin state—provides essential insights into their evolution, taxonomic classification, and potential impact threat.

In this work, we present a thorough analysis of the absolute magnitude and slope...

The Pulsar kinetic Impact technology would allow humanity to literally sleep through the threat of a comet or asteroid which posed a threat to Earth. The Pulsar motor is designed to harness nuclear plasma technologies through a direct fusion drive.
Specifications Below:
The Direct Fusion Drive is a revolutionary steady-state fusion propulsion concept, based on a compact fusion reactor. It...

Multiphysics simulations involve a number of modeling choices, including material strength, meshing strategies, and equation of state. These methods are often verified using ideal scenarios (e.g., uniform mesh, analytic solutions available), but there are scenarios during which this approach is not feasible. Planetary defense, a research subject focused on protecting Earth from impacts from...

We present the use of the University of Tasmania's (UTAS) optical and radio telescopes to conduct observations of near-Earth objects from 2021 to 2024. The Canberra Deep Space Communications Complex transmitted at 7159.45 MHz, with the radar echo detected by the UTAS radio telescopes. The method of accounting for the Doppler shift between the stations and the near-Earth object will be...

Keywords: Near-Earth Objects, Radar, radio telescopes, binary asteroid

From 2019 to 2022, the ESA funded the “NEO Observation Concepts for Radar Systems” pilot project, aimed at the future development of a European radar system for NEOs, enhancing planetary defense, mission planning, and advancing the scientific study of Near-Earth Objects. Contributions from INAF, SpaceDyS, and the...

Meteoroids are the solid remnants of asteroids and comets, ranging from micrometres to decametres in size. Upon entering Earth’s atmosphere, they follow a ballistic trajectory that is partly determined by their composition and internal structure. They display a variety of behaviours including harmless disintegration, meteorite deposition (e.g: Nqweba), explosive airbursts (e.g: Chelyabinsk),...

The Vera Rubin Observatory Legacy Survey of Space and Time (LSST) will provide an unprecedented number of potential Near-Earth Object (NEO) discoveries. Many of these new NEO detections will require additional detections for confirmation and orbit refinement. While follow-up strategies have been actively developed, it is expected to take a significant dedicated amount of time and resources to...

Rapid reconnaissance and characterization of asteroids and comets is one of the stated priorities for planetary defense in the 2023 decadal survey on planetary science and astrobiology1. Traditional asteroid reconnaissance spacecraft like OSIRIS-REx, Lucy, or Psyche have years long development cycle to launch, extensive post-launch trajectory arrival times, and cost hundreds of millions of...

Keywords: Rapid Response, Reconnaissance Spacecraft, Mitigation Spacecraft, Short-Warning Time

The Planetary Defense Community has worked tirelessly over the last 30 years to detect and catalog potential asteroid and comet impact threats to the Earth. Great progress has been made in our knowledge of the compositions and orbits of the millions of asteroids and comets in the solar system....

To assess the risk of an impact from a Near Earth Object (NEO), it is crucial to estimate both the size and density of the object. These estimations can be more easily inferred if the albedo of the object is known. In this context, polarization observations are a key tool for swiftly determining the size of a NEO, and consequently, their potential threat to Earth.

The degree of linear...

Konkoly Observatory is conducting the most successful NEO survey project in Europe with a total number of NEOs found in the past four years in excess of 250, with three imminent impactors discovered between 2022 and 2024. Recently, supported by the European Space Agency, we started the implementation of a new search technique that is using machine learning algorithms to accelerate real-time...

Keywords: planetary defense, reconnaissance mission, asteroid impact, NEOs

If an asteroid or comet is found on a potential Earth-impact trajectory, a top priority should be to reduce uncertainties in whether the object will impact the Earth and in the potential consequences of the possible impact. Ground- and space-based telescopes will provide essential data for reducing some...

Keywords: asteroid flyby, asteroid reconnaissance, mass estimation, mass uncertainty

The near-Earth object (NEO) discovery rate has increased in recent years, and the discovery rate is expected to further increase dramatically when new telescope systems such as LSST and NEO Surveyor come online during the next several years. Significant increases in NEO discovery rate makes it more and...

Performing a stable and robust surface landing on small celestial bodies is essential for future scientific exploration and planetary defense missions. However, in practical missions, due to the weak gravity and complex surface topography, the widely adopted rigid landers are prone to rebound or overturning upon touchdown. This paper reviews a novel landing mode, namely the flexible landing,...

Keywords: Risk perception, public awareness, near-Earth objects, research design, emergency management

Near-Earth Objects (NEOs) are a low probability-high consequence hazard with potentially catastrophic impacts. The Chelyabinsk impact in 2014 and recent technological advancements such as the Double Asteroid Redirect Test have brought planetary defense to the fore....

In 2018, a scandal in the space industry raised legal questions that still concern the legal community today. In January of that year, a US start-up launched four Cube satellites using an Indian rocket without holding an FCC license to use communications technology on these satellites. While this illegal use of the satellites was ultimately punished with a $900,000 civil penalty, it...

Satis is an ESA planetary defence mission study. The mission consists of a stand-alone 12U-XL CubeSat that aims to rendezvous with a Near-Earth Object (NEO). Satis serves as pioneer to demonstrate a completely new class of small, fast-response missions for planetary defense. Here, we present the Satis mission and its science and planetary defence objectives.

The main objectives of the...

Near-Earth object (NEO) impacts pose a significant risk to the Earth, with potential consequences ranging from localized destruction to global-scale environmental disruptions. A critical aspect of NEO consequences is the vapor and ejecta distribution, which can cause environmental consequences far from the impact site and even globally due to atmospheric effects. Using a suite of 2D and 3D...

Keywords: Long Period Comets, Meteor Showers, Early Warning

We describe a software tool that can be used for planning dedicated searches for long-period comets based on the projection of their meteoroid streams against the sky.

Long period comets with orbital periods in the range 250 to 4000 years produce dense enough meteoroid streams to be detected as meteor showers on Earth [1]. Those...

Please see attached PDF.

Acknowledgement
Funded by the European Union (ERC, TRACES, 101077758). Views and opinions expressed are however those of the author(s) only and do not necessarily reflect those of the European Union or the European Research Council. Neither the European Union nor the granting authority can be held responsible for them.

Keywords: Communication, Asteroids, Comets, meteorites, Space Situational
Awareness

Sorvegliati Spaziali – Looking Up to Space to Protect Our Planet is a communication project by the Italian National Institute for Astrophysics, endorsed by NASA’s Planetary Defense Coordination Office Outreach Office. It represents one of the world's first coordinated, comprehensive, and coherent public...

Keywords: Near-Earth objects, radar observations, radio telescopes
Astronomical radar observations have been used to probe surfaces of all the solid planets and many smaller bodies in the solar system. This led to a growing interest in the use of radar to characterize near-Earth asteroids (NEAs) and determine their orbits more precisely. There
is a three-fold motivation for performing radar...

Abstract
Apollo and ATEN class asteroids representing a hazardous form of deep space debris, are now being routinely monitored and researched from the Southern Hemisphere longitude of Australia. A bistatic radar and optical program developing since 2015, brings together the resources of the Universities of New South Wales, Tasmania, Western Australia, Curtin and Federal agencies CSIRO and...

Telescopic characterisation of asteroids and the study of meteorite geochemistry in the lab are fundamentally linked: they study the same objects. However the two disciplines have been mostly disjointed so far, if we exclude the handful of asteroid sample return missions. If we can detect and characterise an asteroid while it is in space, and recover meteoritic samples of it after it impacts,...

The first NEO observations were conducted in 2017 using the new wide-field telescope of the “Sazhen-S” quantum-optical station of the National space Facilities Control and Test Center (NSFCTC) of the State Space Agency of Ukraine. Regular observations, including the follow-up of new objects discoveries, began in 2019. By the end of 2024, three telescopes of NSFCTC in different parts of Ukraine...

This time, we have time. 2024 PDC25 takes 16 years, 10 months, 2 weeks, and 6 days from its fictitious discovery to its fictitious impact on Wednesday, April 24th, 2041 – and it will, because this is an exercise! 2021 PDC was not so kind, leaving us only 6 months to play with it. The coming close encounter of (99942) Apophis on Friday, April 13th, 2029, when it will get to within 31650 km...

Keywords: Near-Earth Objects, Astrometry, Orbit determination
The increasing availability of astrometric data from a wide range of observatories requires a full statistical evaluation of their performances to ensure reliable orbit determination for small bodies, particularly Near-Earth Objects (NEOs). This study presents a systematic statistical analysis of astrometric post-fit residuals for...

The powerful method of stellar occultations is an unbeatable technique uniquely approaching, in some aspects, the performances of planetary space missions. It allows to derive, from ground using small aperture telescopes, asteroids' positions at Gaia-level accuracy [F22], thus extending the time- coverage of Gaia ESA mission. Moreover, it allows to determine the physical size of these...

As demonstrated by the Chelyabinsk event on February 15, 2013, collisions of small (decameter-class) Near-Earth objects (NEOs) with the Earth pose a danger to inhabitants of our planet. These bodies are faint and can only be systematically detected in near-Earth space. Moreover, half of these bodies approach the Earth from the day-time sky and can only be detected by special space-borne...

Since implementing the warning network systems for near-earth objects and bolide events, everything has changed for the safety of the planet [1, 2]. However, this has not been the case in the past, as
in the case in 1908 in Tunguska, Siberia, when an extraterrestrial object burned around 2150 km2 without any injury. Nowadays, the IAWN (International Asteroid Warning Network) is tasked with...

The threat of asteroid impacts on Earth has driven the development of advanced deflection technologies, forming a cornerstone of planetary defense strategies. This paper reviews the latest advancements and challenges in asteroid deflection technologies, focusing on kinetic impactors, gravity tractors, nuclear explosive devices, and hybrid methods. Each technology is evaluated for its...

Rapid reconnaissance flyby missions represent the fastest means of characterizing a potentially hazardous asteroid in a planetary defense scenario. Flyby trajectories can often reach the asteroid with launches every year and cruise durations as short as months. In these scenarios, the design, fabrication, and testing of the spacecraft is the longest duration event in the overall timeline. In...

The Near-Earth Objects Coordination Centre (NEOCC) is the main component of the Planetary Defence Office (PDO) within ESA's Space Safety Programme. Its mission is to support and coordinate the observations of small Solar System bodies and to assess and track the threats they may pose to Earth. Central to this mission is Aegis (1), an automated orbit determination and impact monitoring system...

Keywords: Catastrophic Disruption, Kinetic Impactor, Laboratory Experiments, Numerical Simulations

NASA’s DART mission successfully altered the orbit of a 160-m-diameter asteroid, demonstrating kinetic impactor technology for Planetary Defense. While successful, the DART mission also raised new questions about the extent at which kinetic impactors could be used in real scenarios. In...

The binary asteroid (285263)1998 QE2 is one of the largest PHAs known, measuring 3.2km with a 800m satellite, with the last known closest approach to Earth of 0.039 au (~15 lunar distances) on May 31st, 2013. During the 2013 approach, high-resolution radar data was collected at the Arecibo Observatory and Goldstone helping with physical and dynamical characterization of the system. With the...

The thermal infrared imager TIRI was developed for the ESA Hera mission, which was launched on 7 October 2024 by the SpaceX Falcon9 launch vehicle from the Cape Canaveral Space Force Station. Hera will rendezvous with the S-type near-Earth asteroid binary 65803 Didymos and its moon Dimorphos in December 2026, and perform a six-month-long observations there for the purposes of planetary defense...

PDC2025
Stellenbosch, Cape town, South Africa

Conference Topic: NEO Characterization (or Public Education and Communication)

Towards angular and rotation tracking of Apophis with Meade telescope in 2029: Citizen science tracking ISS and presenting on public education site

Aron Wolf Siegel(1), Hugo de Jong(2), and Nahum Melamed(3)
(1)Innofacer, Turfschip 328, 1186XZ Amstelveen, the...

To raise awareness of the potential threat that Near-Earth Objects (NEOs) might pose to life on Earth, the 2025 Planetary Defense Conference proposes a hypothetical asteroid impact scenario with the discovery of the “2024 PDC25” asteroid. To address this exercise, this work investigates different mission scenarios to conduct a spacecraft toward the asteroid and simulate an impact. Different...

The destructive power of an NEO impact is closely tied to its mass. Especially in the period prior to or in the absence of a reconnaissance mission, an impactor mass must be determined using an estimated size, and it is this estimated size that is reported in official IAWN notifications and used by the international community to plan subsequent actions.

Currently, asteroid size estimates...

Asteroids are of significant scientific and practical interest, as they represent primordial remnants from the early Solar System. Often referred to as the "building blocks" of planets, these celestial bodies offer unique insights into the processes that governed planetary formation and the evolution of other celestial objects. Additionally, understanding asteroid compositions and orbital...

The Space Mission Planning Advisory Group (SMPAG) is one of the two UN-endorsed groups that deals with the asteroid impact threat. The other group is called International Asteroid Warning Network (IAWN). SMPAG members are space-faring nations, and their task is to discuss how a space-based response to an asteroid impact threat could look like [1].
The critera for SMPAG to become active...

Please find the abstract in attachment.

The 2025 Planetary Defense Conference (PDC) hypothetical asteroid impact threat exercise is being conducted in coordination with the United Nations-endorsed Space Mission Planning Advisory Group (SMPAG), enabling an exercise of SMPAG’s process for producing technical recommendations for space mission options using inputs received from space agencies in participating nations. In this paper, we...

In planetary defense exercise scenarios, most discussions of rapid response reconnaissance missions focus on dedicated spacecraft. These are typically new spacecraft, designed and built specifically for the purpose of surveying a newly discovered asteroid that is potentially threatening Earth. A new reconnaissance spacecraft takes approximately three to five years to reach the launch pad, and...

The growing interest in addressing asteroid threat scenarios is justified by current estimates of the Potentially Hazardous Objects (PHOs) population and by recent impacts on Earth. Since 2015, exercises involving hypothetical hazardous asteroids have been proposed, with various solutions discussed during Planetary Defense Conferences (PDCs). This paper presents and analyses preliminary...

As part of the SMPAG exercise held this year, the ESA NEO Coordination Centre (NEOCC) contributed in assessing potential impact scenarios for the simulated asteroid 2024 PDC25. By using all the available data at epoch 1 publicly realized in July, we used our Aegis system (1) to compute the orbit and the impact probability (IP) of 2024 PDC25 for the next 100 years. We found an IP of 1.6% in...

In planetary defense scenarios, there is often a limited amount of information about the properties of the object during the early phases. Statistical inference methods which leverage prior knowledge about the population of Near Earth Asteroids have successfully been utilized in PDC and IAWN exercises to augment the available measurements about the specific hypothetical impactor. The physical...

Keywords: asteroid, impact risk, modeling uncertainty

Determining the potential damage and risk from an asteroid impact involves many sources of uncertainty. Limited observational data leads to uncertainties in the asteroid properties, orbital uncertainties affect the potential impact location, and the entry and damage models all have some inherent modeling uncertainty. When each of...

A hypothetical asteroid-impact scenario (http://neo.jpl.nasa.gov/pdc25/) will be used as the basis for discussion and analyses during the PDC 2025 table-top exercise. The asteroid is “discovered” on June 5, 2024, and is classified as a potentially hazardous asteroid with a diameter initially estimated between 90-160 meters with a median size of 125 meters and a full-size range of 50-280...

Keywords: Asteroid Threat Exercise, Earth Impact Effects, Impact Monitoring
Abstract
If the mitigation efforts do not succeed to alter the trajectory of 2024 PDC25, the
asteroid will impact near Cape Town, South Africa, depositing 250 megatons of energy
and creating a crater of about 3 km in diameter. If this happens it would be of obvious
interest to observe this impact in as much detail...

The Hera mission, which is part of the Space Safety Program of the European Space Agency (ESA), was launched on 7 October 2024 from Cape Canaveral with a Falcon 9 rocket. By the time of abstract submission it successfully completed most of its near-earth commissioning activities.

Hera will perform a rendezvous with Didymos in the fall of 2026 and investigate it over 6 months. With NASA’s...

Our knowledge of the internal structure of asteroids relies entirely on inferences from remote sensing observations of the surface and theoretical modeling. Is the body a monolithic piece of rock or a rubble-pile, and how high is the porosity? What is the typical size distribution of the constituent blocks? Are these blocks homogeneous or heterogeneous? Direct measurements of an asteroid’s...

On April 13, 2029, (99942) Apophis with a diameter of about 340 meters will approach Earth’s surface at about 31,000 km. Significant tidal torques will be exerted on Apophis, with possible alterations of its rotation state and internal structure, measurable seismic waves and real-time surface disturbances. This very close Earth flyby presents an unprecedented planetary defense and science...

The OSIRIS-APEX spacecraft will characterize asteroid (99942) Apophis over 18 months in 2029 and 2030 [1-3]. The mission is split into phases designed to address specific scientific objectives [3]. Because of the long period and non-principal axis rotation of Apophis, APEX will observe at regular intervals every few hours as it moves through multiple observing geometries to build up coverage...

The planetary defense is an important activity for humankind. JAXA has been involved in this activity for long time, and recently Planetary Defense Team has been established and started to work.
The first thing to do for the planetary defense is to discover celestial bodies that will collide with the Earth and to estimate their orbits accurately. We carry out observations of Near-Earth...

Hayabusa2# is an extended mission of Hayabusa2, which will spend another decade conducting various scientific and engineering investigations highlighted by a flyby at Asteroid (98943) Torifune in 2026 and a rendezvous with Asteroid 1998 KY26 in 2031. Our space flight operations have continuously performed cruise science investigations of exoplanets, comets, and zodiacal light. Recently, the...

To be able to provide advanced warning of future or imminent impacts of asteroids or comets, the first step is to observe the sky and discover these objects by means of dedicated NEO surveys. Most current and planned NEO surveys are ground-based and carried out in the visible wavelength range. However, this approach has some limitations, such as (1) weather dependency, (2) that only a portion...

99942 Apophis was a target of intense optical and radar observing campaigns during the 2012--2013 apparition when the asteroid approached Earth within 0.097 au. Radar observations were obtained on 19 days between 2012 December 21 to 2013 March 16 Brozovic et al. (2018) and lightcurve observations were obtained on 49 days between December 23 and April 15 Pravec et al. (2014). Brozovic et al....

Asteroid Apophis rotates in an excited rotation state described by two periods, rotation and precession, with the values of 263 h and 27.38 h, respectively. Together with other spin parameters and a convex shape model, these periods were derived by [1] from photometric observations carried out in 2012/13. Radar observations are consistent with the spin state derived from light curves, and the...

On April 13, 2029, asteroid (99942) Apophis will pass within 32,000 km of Earth, offering a unique opportunity to study how Earth’s tidal forces affect asteroids, particularly those with complex internal structures. This study investigates possible mass shifts and structural changes within Apophis during its close encounter, focusing on the implications of its bilobed shape, resembling a...

The upcoming close encounter of asteroid 99942 Apophis with Earth in 2029 presents a once-in-7000-year opportunity to study the dynamics, bulk properties, and interior structure of a potential rubble-pile asteroid as it passes through Earth’s gravitational field. Numerical modeling—including via Discrete Element Methods (DEMs)—has helped to develop our understanding of the dynamics and...

The close approach of 99942 Apophis, on April 13th, 2029, will offer a wide portfolio of scientific opportunities to study a near-Earth asteroids physical and orbital properties and how these are affected by close approaches with planets. Yet, although its probability of impact with our planet was definitively ruled out in March ’21, the extraordinary event of a ~ 375 m diameter object and an...

Near-Earth asteroid (NEA) 99942 Apophis is interesting because it will make an exceptionally close approach of the Earth in 2029 at a geocentric distance of 38,000 km making it the closest known flyby by a large NEA. The International Asteroid Warning Network (IAWN) conducts campaigns to test the operational readiness of the global coalition of observers, modelers, and decision makers to...

The flyby of Apophis in 2029 offers an opportunity to prove out rapid planetary defense mission concepts from Earth orbit. We will present a mission concept developed at Lawrence Livermore National Laboratory that achieves key planetary defense objectives of characterizing Apophis with two small satellites placed in flyby orbits from GTO. The spacecraft will be equipped with 25cm aperture...

The Near Earth Object (NEO) 99942 Apophis provides a unique opportunity for an operational Planetary Defense (PD) scenario. Discovered in 2004, Apophis was initially identified as a highly hazardous asteroid that could impact the Earth. Dedicated tracking campaigns have allowed scientists to eliminate any risk of impact during the April 13, 2029 flyby; however, Apophis will pass within less...

The close flyby of asteroid (99942) Apophis on April 13, 2029 presents a unique
opportunity to achieve scientific and planetary defense goals. A multi-spacecraft
mission concept to exploit this opportunity has been developed in a collaboration
between Caltech, JPL and CNES. The Caltech-led mission is being pursued as a
privately funded venture with commercial partners. Its architecture...

An understanding of both surface and interior properties of potentially hazardous objects enables accurate characterizations of their geological and geophysical conditions for planetary defense purposes (e.g., risk assessment and impact mitigation), in addition to their formation and evolution mechanisms relevant to planetary science investigations. Asteroid 99942 Apophis will fly by Earth...

The $\sim$325-meter diameter Potentially Hazardous Asteroid (PHA) designated 99942 Apophis 2004 MN$_{\text{4}}$ will make a historic close approach of Earth on April 13th, 2029, passing within $\sim$31,634 km of Earth’s surface, $\sim$4,152 km closer than our geosynchronous satellites. This is an extraordinarily unique opportunity for collecting data on a several hundred-meter size asteroid...

The physical properties of potentially hazardous small bodies are critical for planetary defense studies. The Sq-type asteroid (99942) Apophis, an Aten asteroid with an Earth-crossing orbit, will pass within ~32,000 km of Earth on Friday April 13, 2029. This close encounter could induce surface alterations of Apophis, such as landslides and mass wasting, due to gravitational interactions with...

We define a mission concept to perform a cratering and deflection experiment at Apophis with an independent impactor spacecraft that leverages the formidable capabilities of OSIRIS-APEX as an observer. This is relevant to both planetary defense and science.

A 65kg spacecraft impacting Apophis at 7km/s will make a crater between 20-50m [1,2], and result in an excavation of 2-8m deep. This is...

The Pan-STARRS-1 telescope in Maui, Hawaii performed a multi-purpose survey of the of the sky north of -30° declination from 2010 to 2014. From 2014 onwards, the main focus of Pan-STARRS has been a survey of the sky for Near-Earth Objects (NEOs), funded by the NASA Planetary Defense Program. With the addition of the second telescope, Pan-STARRS has become one of the leading surveys for...

The Catalina Sky Survey is a world leader in the discovery and astrometric follow-up of near-Earth objects (NEOs) As such, we continuously update and refine our algorithms to improve our operations. Here, we present three recent enhancements to the Catalina Sky Survey operations model in both discovery survey and targeted follow-up.

First, we have recently, in collaboration with the ATLAS...

The ATLAS telescopes have largely operated using a traditional discovery mode in which data from each telescope are processed separately and NEOS are discovered from a series of four "quad" observations from one telescope. Since they operate independently, sky coverage (and therefore NEO discovery) are subject to losses from poor weather; for example, a quad of observations can be spoiled by a...

To detect unknown and potentially dangerous asteroids, ESA’s Planetary Defence Office prepares the operation of a network of so called FLYEYE telescopes.
ESA’s Test Bed Telescope (TBT) project is laying the groundwork for the efficient operation of these telescopes. The project consists of two identical telescopes: one located at ESA’s ground station in Cebreros, West of Madrid in Spain, and...

2022 EB5, 2023 CX1 and 2024 BX1: these are the three recent imminent impactor discoveries from the Piszkesteto Mountain Station of the Konkoly Observatory. They make up about a quarter of all known such events since 2008 and one may ask what makes our survey sensitive to these little impactors. In this talk we describe our recently upgraded survey instrumentation, outline the observational...

We simulated the operations of the Vera C. Rubin Observatory in observing 5,000 virtual impacting asteroids over a range of size bins, whose orbits were chosen to impact Earth over a period of 50 years. We used the Sorcha package to simulate the observations of these impactors for the planned 10-year Legacy Survey of Space and Time. We performed running orbit fits for the state vector and...

The airburst event over Chelyabinsk, Russia in 2013 caused over 1,400 injuries and $30 million in property damage. This object was not tracked until it entered the Earth’s atmosphere, too late for any disaster response, partly because of its small (~20 meter-diameter) size, but also because it approached from interior to Earth’s orbit, obscured by the Sun’s brightness. The Chelyabinsk...

Keywords: Near-Earth asteroids, NEOCP, MPC, impactors

The Minor Planet Center (MPC) serves as the single worldwide location for tracking and cataloging asteroids, natural irregular satellites of the major planets, and comets, making it central to planetary defense efforts. Operated at the Smithsonian Astrophysical Observatory in Cambridge, MA, under the auspices of the International...

Over the past two decades, nearly all Near-Earth Objects (NEOs) have been discovered mostly by dedicated surveys through the use of preselected candidates posted to the Minor Planet Center's (MPC) Near-Earth Object Confirmation Page (NEOCP). Rapid follow-up observations from the astronomical community typically allow for the designation of new NEOs within a few days. As of today, more than...

The motion of an asteroid over its hour long ''tracklet'' (a short sequence of observations) is often used to estimate the likelihood of it being interesting [1] -- that is, not exhibiting the motion typical of main belt asteroids. This is done by computing a numerical score, 0-100, which must be >65 for the object to be considered a Near-Earth Object (NEO) candidate.

However, there are...

A common question from the public is: How many dangerous asteroids could potentially hit the Earth? Our response usually starts by mentioning that the number is size-dependent, because while there are numerous small asteroids, they pose less threat to life on Earth.

We have agreed to use two limits: 1km objects for global catastrophes and 140m objects for regional events.

In the last 25...

Impact risk is normally quantified by summing the product of the probability of an event and some measure of its consequences over the set of all possible events. The probability factor is considered to be more objective and is based on the size frequency distribution of NEOs and an implicit assumption of randomness, which can be described as “stochastic catastrophism”. Impact frequency does...

NASA’s Near-Earth Object (NEO) Surveyor mission is an infrared observatory planned to launch no earlier than September 2027 that is designed to discover and characterize asteroids and comets. Its main objective is to identify those objects that are large enough (>140 m in effective spherical diameter) to cause severe regional damage from impact. The observatory will operate at the Sun-Earth L1...

The United Nations established the International Asteroid Warning Network (IAWN), in 2013 to coordinate worldwide organizations involved in detection, tracking, and characterization of Near-Earth Objects (NEOs). In addition, developing well-defined communication plans and protocols to assist governments in the analysis of asteroid and comet impact consequences and in the planning of mitigation...

Asteroid impacts have profoundly affected the evolution of life on Earth. Over the last 30-40 years, the field of planetary defense has identified the scope of the threat and is working to develop plans and technology to prevent asteroid impacts if possible and mitigate their effects as necessary. In particular, if an object were on a collision course with the Earth, early knowledge of key...

Observational capabilities are one of the key “pillars” of ESA’s Planetary Defence Office activities. This presentation will highlight recent developments, important results and key objectives of our follow-up efforts.

We will begin with an overview of the status and recent additions to our global network of fast-reacting facilities, which are playing a critical role in our follow-up of the...

The Goldstone Solar System Radar on NASA’s 70 meter DSS-14 antenna is the world's most sensitive planetary radar. DSS-14 is equipped with a high-power (~450 kW) radar used for observations of near-Earth asteroids (NEAs), comets, and other solar system targets. Goldstone transmits at a frequency of 8560 MHz (3.5 cm), is fully steerable, routinely tracks down to a declination of -35 degrees,...

Many newly discovered near-Earth asteroids (NEAs) are small ($<$100 m), yet they still pose significant risks if they impact Earth. Therefore, continued research and observation are crucial for the small NEA population, where characterisation significantly lags behind discovery rates. Our program at the South African Astronomical Observatory (SAAO) utilises the robotic capabilities of the...

Near-Earth Objects (NEOs), encompassing both asteroids and comets, are celestial bodies whose trajectories bring them into proximity with Earth, presenting both scientific opportunities and potential collision risks. A comprehensive investigation of their physical characteristics, dynamical behaviors, and orbital evolutions is paramount for planetary defense strategies and advancing...

The 4.3-m Lowell Discovery Telescope (LDT) is a highly efficient facility for the characterization of near-Earth objects. With multiple instruments simultaneously mounted, a combination of astrometric, photometric, and spectroscopic measurements are regularly made. Recent observations at LDT have focused on NEOs such as imminent impactors (2022 WJ1, 2024 XA1), mini-moons and lunar ejecta (2024...

In November 2024, ESA’s Planetary Defence Office (PDO) organized the EU-ESA workshop on size determination of potentially hazardous near-Earth objects, held at ESOC in Germany [1]. The workshop explored how the minor body community can improve the size determination of NEOs. For an Earth impacting object, its size is the key factor in assessing potential ground damage [2]. Newly discovered...

A critical component of planetary defense is accurately assessing the size and surface properties of potentially hazardous asteroids and impactors. Observations and modeling of an asteroid's thermal emission, which depends on its surface temperatures, lead to a direct size determination \citep{2015aste.book..107D}. Characterizing surface properties such as thermal inertia and roughness...

Abstract attached as a PDF file as required according to the guidelines.

Near-Earth object (NEO) models are a useful tool for interpreting asteroid behaviour in near-Earth space (perihelion distances < 1.3 au). They can predict many asteroid properties such the size-dependent transport from the main-belt (Granvik et al., 2018; Nesvorný et al., 2023) and the disruptive processes of low perihelia passage (Granvik et al., 2016; Wiegart et al., 2020). They can also...

Keywords: Meteorite, meteor, Asteroid, Asteroid Families, Source Regions

To date, 74 meteorite falls have been instrumentally recorded by video cameras and still photographs and their pre-impact orbit determined. Two of which are the fall of Saint-Pierre-le-Viger from asteroid 2023 CX1 in France and the meteorite Ribbeck from asteroid 2024 BX1 in Germany.

A recent review paper takes...

Keywords: Gravity Tractor, Slow-pull Mitigation Technique, Binary Asteroids, Mission Concepts

There are a number of possible mitigation strategies that have been identified in the event a hazardous asteroid is discovered. NASA’s DART mission recently demonstrated the kinetic impactor technique [1]. The gravity tractor (GT) is attractive as the next technology for demonstration since other...

The Double Asteroid Redirection Test (DART) mission was a successful planetary defense demonstration of a kinetic impactor on Dimorphos, the satellite of binary near-Earth asteroid 63803 Didymos (Daly et al. 2023). The DART impact changed not only the orbit of the satellite Dimorphos about Didymos (Thomas et al. 2023), but also the orbit of the Didymos system about the Sun (Makadia et al....

Several techniques may be appropriate for deflecting a threatening asteroid on a collision course with Earth. Slow-push techniques, such as gravity tractors, require long lead times. Fast-push techniques such as nuclear standoff bursts require much less lead time but come with a host of additional issues. Kinetic impactors are an alternative fast-push technique that can be used on...

The vast majority of asteroids that pose a threat to Earth have a complex distribution of porosity due to their rubble-pile configuration. As of right now the only proven method for deflecting these potentially hazardous bodies is to use a kinetic impactor, as was demonstrated by the Double Asteroid Redirection Test (DART) mission. Kinetic impacts change the momentum of the target asteroid...

HYPERVELOCITY CRATRING AND DISRUPTION OF THREE L-TYPE ORDINARY CHONDRITES

George J. Flynn(1), Melissa Strait(2), Daniel Durda(3) and Robert Macke(4)
1Dept. of Physics, SUNY-Plattsburgh, 101 Broad St., Plattsburgh, NY 12901 USA (01-518-564-3163, flynngj@plattsburgh.edu),
2Dept. of Chemistry, Alma College, Alma, MI 48801 USA (straitm@alma.edu),
3SwRI, 1050 Walnut St., S-300, Boulder CO...

In an idealized mitigation scenario, one would strive for threat interception to occur as far away–in both space and time–from Earth as possible. However, reality may make such a desirable outcome improbable to impossible, due to hurdles like uncertainty in the threat's characteristics or lack of time for preparation. In a scenario where extended warning time and preparation are out of reach,...

Certain planetary defense scenarios may require the use of nuclear explosive devices (NEDs) for successful mitigation [1]. Planning for these scenarios use engineering models derived from hydrocode simulations, themselves built upon models of x-ray energy deposition in asteroid material [2]. Recent work [3] has advanced the state-of-the-art in energy deposition modeling using...

This study presents a groundbreaking experiment that explores the deflection of Near-Earth Objects (NEOs) using x-rays generated from a stand-off nuclear explosion for deflecting the largest NEOs or for short impact warning times. Conducted at the Z Machine at Sandia National Laboratories, our innovative approach utilized an intense x-ray burst produced by an argon plasma, targeting miniature...

Planetary defense mitigation attempts require significant advanced mission planning and simulation. The modeling work is conducted using hydrodynamics codes and equation of state data (Barbee et al., 2018). The results of these pre-launch simulations are used in mission planning to predict targeting and timing requirements and to quantify the energy and delivery mechanism required to deflect...

Keywords: Nuclear mitigation modeling, deflection, disruption, hydrocode

Asteroid impacts are serious natural disasters that may result in regional to global damage depending on the object’s mass and incoming velocity. However, with adequate preparation time, we may be able to prevent impacts from happening. One such mitigation method is the “kinetic impactor” method, which involves...

Asteroid impacts, though infrequent, have the potential for catastrophic consequences. Space missions offer the possibility of averting such disasters, provided there is adequate warning time and decisive action. Successfully mitigating a potential asteroid impact relies on decision-makers swiftly comprehending the complex mission space and committing to a course of action with enough time for...

Keywords: Planetary Defense, Flyby, Spacecraft Reconnaissance, Near-Earth Object

International and U.S. strategies have identified the need to develop spacecraft reconnaissance capabilities as a priority to advance planetary defense readiness. The UN-endorsed Space Mission Planning Advisory Group and the US Report on Near-Earth Object Impact Threat Emergency Protocols recommend planning a...

Thanks to the success of NASA's DART mission, the Kinetic Impact (KI) method is the only tested way of deflecting Near-Earth Asteroids (NEAs) away from the Earth [1]. However, one important consideration with KI deflections is the potential of disrupting the target while trying to deflect it. A disruption can happen if the NEA is small or if the relative impact momentum of the deflection...

The discovery of a new Near-Earth Object (NEO) with a significant probability of impacting the Earth will inevitably lead to threat mitigation strategies. Three key questions for threat mitigation are: (i) what is the probability that the object impacts the Earth?; (ii) Is the object large enough to threaten loss of life or property?; and (iii) what are the key characteristics of the object...

The 2023 National Academy of Sciences, Engineering, and Medicine Decadal Survey on Planetary Science and Astrobiology lists several key questions regarding the collisional, dynamical, and physical evolution of small body populations in the solar system. Among those objects are Temporarily Captured Orbiters (TCOs), a subset of near-Earth objects (NEOs) that enter the Earth-Moon system and...

As part of the ALCOR program, the Italian Space Agency (ASI) is funding the "Asteroid Nodal Intersection Multiple Encounters (ANIME)" CubeSat mission, which successfully completed Phase A in 2024. The aim is to develop a 12U CubeSat tailored for the exploration of multiple near-Earth asteroids (NEAs) encountered during their transits through their orbital nodes.

ANIME's baseline mission...

The lessons of reusing and repurposing mission assets are relevant to Planetary Defense and Small Body Science objectives, as expressed in the most recent decadal survey for Planetary Science and Astrobiology. As described in [1], the European Service Module (ESM), the element of NASA’s Artemis Program that returns the Orion Crew Module to Earth (Figure), currently is planned for destruction...

A mission to NEA (99942) Apophis would provide a unique opportunity to collect and return a regolith sample from a NEA as it passes very close to Earth. ESA is currently investigating the possibility of an orbiter, as part of the RAMSES mission study, to fly close to (99942) Apophis before it makes its closest approach to Earth on Friday, April 13, 2029, with the aim of observing the tidal...

Introduction. The Milo Space Science Institute, a nonprofit entity co-founded by Arizona State University (ASU) and Lockheed Martin (LM), in partnership with the University of Colorado at Boulder (CU), aims to conduct a pioneering reconnaissance flyby of (99942) Apophis approximately 1 year before its close approach to Earth in April 2029. The mission, called Apophis Pathfinder, would...

On the 13th of April 2029, Apophis, a 400 meter asteroid, will pass within 31 600 km of Earth’s surface in a retrograde orbit, moving through the magnetosphere and encountering the outer radiation belt, ring current, and outer edges of the plasmasphere. Therefore, this event offers a fantastic opportunity to investigate how small scale airless bodies interact with Earth’s magnetosphere.

The...

Ion-Beam (IB) deflection is one of three primary mitigation techniques evaluated for use in the 2025 PDC hypothetical asteroid impact exercise. Unlike the other two techniques, Kinetic Impactors (KI) and the use of Nuclear Explosive Devices (NEDs), the ion-beam option is a gentle, slow-push method that, over the course of months to years, can change an asteroid trajectory significantly without...

The atmospheric breakup of an incoming asteroid and deposition of its energy into both the atmosphere and ground is of great interest to the planetary defense community. The breakup of an incoming asteroid will heat the atmosphere and generate a shockwave and is highly dependent on the asteroid’s size, physical characteristics, and incoming trajectory. In this contribution, we analyze how the...

In the PDC25 scenario at initial assessment, the asteroid may impact nearly vertically over Cape Town or at increasingly shallow angles moving north over Africa and Europe. This presentation will compare the predictions for blast and thermal damage from coupled radiation-hydrocode simulations using the ALE3D hydrocode and the NERO thermal radiation transport code.

For height-of-burst...

Super-bolides are of particular interest to planetary defense since they can release
vast amounts of energy (500 kton to >10 Mton) during atmospheric entry. Superbolides
such as Chelyabinsk (20m, 2013) and Tunguska (50m, 1908) are two
contemporary examples of the effects airburst phenomena have, ranging from minor
structural damage to prominent land devastation. Smaller scale celestial...

Please find attached an extended abstract for PDC2025 (9th IAA Planetary Defense Conference).

I am the corresponding author, and can be reached at:
michael.aftosmis@nasa.gov

Asteroid strikes can cause extensive blast damage to surrounding regions, either by impacting the surface or bursting explosively during entry. The severity and extent of the resulting blast damage areas depend both upon the energy of the airburst/impact and the airburst altitude at which most of that energy is deposited into the primary blast. For a given blast energy, there is an ‘optimal’...

Initial effects of asteroid impact and airbursts include thermal radiation and overpressure blast waves. If sufficiently large asteroid fragments reach the surface, seismic activity or tsunamis may occur if over land or sea, respectively. However, other effects that could extend the geographic areas affected and/or result in long-term physical hazards are less characterized. We categorize...

Keywords: blast, overpressure, Lamb wave, airburst, tsunami

Atmospheric entry and disruption of very large bodies produces blast waves with damage radii reaching hundreds or even thousands of kilometers. Recent 3D computational simulations of large impactors (above roughly 1 Gt kinetic energy at entry) demonstrate that these large blasts initially expand roughly spherically and then...

Meteorite terrestrial impacts are established as the causes of large circular geological structures, major crustal deformations, large volumes of displaced rocks, extensive ejecta, and ultimately non-ideal debris cloud formation. Statistically, these are rare events, and the physical processes involved in terrestrial impacts and their subsequent induced effects, such as cratering, ejecta...

This paper builds on the 2024 developments within SMPAG and my recently published arguments in Acta Astronautica and Nature Communications. It offers the scientific community and SMPAG delegates a comprehensive roadmap aimed at fostering cooperation in the event of an asteroid being detected on a collision course. The proposed approach seeks to mitigate the challenges typically posed by...

Planetary defense, the protection of Earth from hazardous Near-Earth Objects (NEOs) such as asteroids and comets, has emerged as a critical interdisciplinary challenge that intersects space technology, international law, and global cooperation. Current frameworks like the Outer Space Treaty (1967) \cite{dembling1967evolution} and its associated conventions establish principles for the peaceful...

Most efforts to look at Planetary Defense have only considered protecting the Earth. But there are now concrete plans to establish human settlements and other significant infrastructure on the surface of the Moon over the course of the next several decades. This puts the people – and strategic assets – there at risk from asteroid impacts.

The past several decades have seen our species make...

Abstract
The main aim of planetary defense is to keep Earth safe from any possible asteroid collision which is an essential component of space exploration. The particular issue of liability can be raised by conducting such missions while the existing international legal framework lacks any such treaty, laws, rules, or regulations regarding liability from planetary defense missions. This paper...

Deflecting a hazardous near-Earth object (NEO) away from Earth impact may be done using a variety of techniques. Deflections may be categorized according to whether they are designed to be accomplished, in principle, with a single action, or whether they are designed to require multiple actions spread across time.

An NEO might be deflected with a single kinetic impactor (KI) or a single...

Theoretical studies have considered use of nuclear explosive devices (NEDs) to deflect hazardous near-Earth objects (NEOs) for decades. Questions about how this would work in international relations, especially with respect to the Outer Space Treaty and the Partial Test Ban Treaty, have lingered though—making policy planning and international discussions difficult. Many discussions conclude...

Keywords: planetary defence, nuclear weapons,NPT, legality

Numerous so-called asteroid impact mitigation techniques have been and continue to be discussed. The range of proposed measures goes from gravity tractors to destruction or deflection of asteroids through nuclear explosions.
Especially when faced with very large objects and only a short warning time, the latter option – namely the...

Keywords: Impact Effects, Political, Legal, Social and Economic Consequences, United Nations.

Abstract
The virtual object of the 2025 PDC exercise assumes an asteroid of about 200 Meters diameter, approaching Earth at 14 km/s with a possible impact in 2041. The risk corridor is a north-south line from northeastern Europe across the Mediterranean, the Sahara, and central Africa towards...

Keywords: Value Focused Thinking, VFT, Planetary Defense Strategy, Brazil

ABSTRACT
Recognised as a leader in Latin America, whether for economic, political or territorial reasons, Brazil has worked to ensure its autonomy in the space sector, despite budgetary constraints and operational difficultie. This is made possible by the National Policy for the Development of Space Activities...

How to detect and deflect asteroids and comets that threaten to impact Earth, and how to mitigate the consequences should an impact be unavoidable, is a vital but complex topic that touches on multiple disciplines, involves multiple stakeholders, and presents multiple options to decisionmakers. Related issues have been extensively researched for many years and a large number of papers,...

Recent recorded instances of asteroid encounters at Tunguska (1908), Chelyabinsk (2013), and other sites show that we are vulnerable to impact hazards and the public are often left ill-informed. More importantly, we have not prepared the public for these threats and how to respond to the wide range of potential asteroid impact hazards, evidenced from the nearly 1,500 reported injuries from the...

Social media has become part of our lives, and for many it is already the main source of information. During the Covid pandemic it became clear that misinformation can put people’s lives at risk. Science communication is relying on trusted sources and the accuracy of the information provided. The planetary defense community is aware of this and is successfully raising the public’s awareness...

One implicit assumption in our planetary defense tabletop exercises is that, in the real world, the participants will be competent and acting in good faith. Recent history demonstrates that this may not be the case. In most of our hypothetical impact scenarios, there will likely be winners and losers. The stakes could be enormous in terms of casualties, economic loss, and geopolitics, and the...

Keywords: NEO, planetary defense, public outreach, asteroids.

Since it was founded in 2006, the Virtual Telescope Project has been a leading facility in sharing online, real-time observing sessions of near-Earth asteroids around the time of their flyby with the Earth. Over more than 18 years, it scheduled and produced hundreds of online events, including the record setting, extremely close...

The Kenya Space Agency (KSA) has implemented an innovative Asteroid Search Campaign designed to promote hands-on activities in Astronomy and Space Science. This initiative has demonstrated significant success in engaging students across university departments, notably triggering a remarkable shift of interest from engineering to astronomical sciences.

By providing experiential learning...

It's Saturday, April 14, 2029. The day before, the Apophis asteroid passed within 40,000 kilometers of the Earth. The time has come to draw lessons from the few months that preceded this unique event in the history of mankind: the information campaign by the scientific community, the exceptional media coverage, the flowering of conspiracy sites of both religious and non-religious obedience,...

Keywords: education, outreach, heritage

Division C of the International Astronomical Union collects together the membership with interests in Education, Outreach and Heritage. The work of the division is highly varied covering astronomy education research, competitions, science communication, astronomy outreach, conservation of historical buildings and instruments, history of astronomy and...

The planetary defense community practices mission-planning to deflect or disrupt any near earth asteroids (NEAs) that are found to be on an Earth-impacting trajectory. Many scenarios must be considered to determine the optimal mission type to recommend. While a kinetic impactor is the first choice for a deflection mission, either a large asteroid or a short warning time may require using a...

Future planetary defense systems may need a variety of modular designed platforms to detect, track, characterize and possibly mitigate PHOs and other objects in space. Multiwavelength sensor platforms, equipped with multiuse interceptors for in situ exploration of the target asteroid, kinetic impact, directed energy systems or nuclear explosive devices, could be a viable, effective solution...

The governance and international cooperation mechanisms central to planetary defence are under-explored in academic research despite their centrality to the success of global efforts to mitigate asteroid and comet impact hazards. This study seeks to address a crucial gap: how effective are current international organisations and frameworks in fostering meaningful collaboration and governance...

Panel 1a: Notification of asteroid ?impact threat and early preparedness

Near-Earth objects (NEOs) pose significant threats to human survival due to their potential for Earth impact. This necessitates the development of monitoring and early-warning technologies for hazardous NEOs. Current monitoring systems rely primarily on ground-based observation networks, which lack the capability for all-day, all-sky monitoring. Consequently, space-based monitoring systems,...

An analysis for a conceptual space borne bolide observatory is presented with a mission to char- acterize the small near-Earth asteroid and comet populations. Specifically, we investigate the utility and feasibility of orbital narrow-band spectroscopy. The informed selection of wavelength ranges has the potential to provide diagnostics with respect to impactor properties such as meteorite...

Abstract

As humanity’s ability to detect and mitigate threats from Near-Earth Objects (NEOs) improves, planetary defence has become a critical focus to protect Earth from potentially catastrophic asteroid impacts. However, the methods employed in planetary defence such as kinetic impactors, nuclear deflection and gravity tractors raise significant concerns regarding the environmental...

The Near-Earth Object (NEO) Toolkit, developed by ESA's Planetary Defence Office, is an advanced suite of tools designed to support observation planning, scientific research and monitoring of NEOs. The NEO Toolkit includes:

1. Orbit Visualization Tool (OVT): A 3D graphical tool for visualizing NEO orbits, including past and future close approaches and impactors, allowing exploration of...