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Description
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 estimated mass of ~ 20 million tons passing inside the Geostationary ring, with a nominal distance of ~ 38000 km from Earth, will pose relevant dynamical challenges and potential risks to Earth's satellite infrastructures, and the unique occasion to study how satellites are affected by bulky asteroids very close approaches.
This paper aims at modelling and analysing the gravitational perturbation introduced by Apophis’ passage on Earth satellites, and to estimate the delta-V budget required to counteract Apophis' gravitational pull and maintain satellite operational orbit. In absence of station-keeping maneuvers, the maximum deviation a satellite's orbit can experience due to Apophis' influence is firstly estimated, examining how it will affect their orbital elements depending on the satellite's orbital characteristics, both for LEO and GEO satellites. An effective station keeping strategy is then implemented, which allows an estimation of the total delta-V budget required to counteract the gravitational pull of the asteroid, validated through simulations on well-known mission analysis high precision software. By understanding the specific effects of Apophis' close approach, this research aims to provide valuable insights into the potential risks and challenges posed by near-Earth object close approaches to satellite operations. These results can be used to develop strategies for mitigating the impact of such events and ensuring the continued reliable operation of satellite systems.