Effect of large constellations on lifetime of satellites in low earth orbits

Dynamical reliability analysis and remaining useful life prediction for an on-orbit satellite camera

“…Moreover, since satellite camera (SC) is the main payload on remote sensing satellites, its on-orbit health state has long been recognized as an essential part of satellites design. However, the dramatic temperature change, space debris 7 and the complicated radiations 8 will cause irreversible damages to SCs. 9 If in-orbit SCs fail, they cannot be repaired and thus the satellite must retire.…”

Prototyping operational autonomy for Space Traffic Management

“…As outer space becomes increasingly congested with satellites, due to miniaturizing hardware, cheaper launches, more automated operations, entry of emerging economies and proposed megaconstellations, the satellite population in Low Earth Orbit (LEO) is expected to grow from ~1000 to over 16000 in 10-20 years [1], [2]. The increased population will be susceptible to greater risk of physical collision with each other or debris, radiofrequency interference, space weather, lasers and directed energy impacts, and thus create more debris exponentially (Kessler Syndrome).…”

Are mercury emissions from satellite electric propulsion an environmental concern?*

“…More recently, the environmental impacts of combustion emissions from rocket engines are being examined (Ross and Vedda 2018). Plans for massive satellite constellations are expected to increase the number of satellites in Low Earth Orbit (LEO, altitude <2000 km) by a factor of ten over the next 10-20 years (Ailor et al 2017, Le May et al 2018, Peterson et al 2018. For efficient orbit raising and orbital station-keeping (maneuvers required to maintain the desired altitude and path), many of these satellites will include electric propulsion systems, predominantly Hall thrusters (Lev et al 2017a(Lev et al , 2017b.…”

“…The potential magnitude of mercury emissions from satellite electric propulsion depends on the propellant mass per satellite and the number of satellites. Satellites in the proposed constellations have masses in the range of 100-500 kg (Ailor et al 2017, Le May et al 2018, and propellant typically comprises a large fraction of the mass of satellites due to the large velocity changes required for orbital maneuvering (Gallimore 2008, Lev et al 2017b. As a representative magnitude, 2000 satellites (the average size of two approved constellations (Federal Communications Commission 2017, 2018)) each containing 100 kg of mercury propellant would emit 20 Mg of mercury per year over a 10 year lifetime.…”