14:00 〜 14:15
[MZZ40-02] Mission Architecture of Deep Space Constellation for Rapid Response and Frequent Asteroid Flyby
キーワード：ミッション設計、深宇宙コンステレーション、即応型探査、小惑星、フライバイ
The U.S. Decadal Survey asserts the importance of rapid-response flyby exploration in planetary defense to understand the characteristics ofhazardous asteroids and to develop effective mitigation strategies. One of the rapid-response mission architectures is to send spacecraft in adedicated launch vehicle as quickly as possible when the target object is discovered. This approach requires a dedicated launch vehicle capable ofrapid response, which poses a high technical and political hurdle for countries including Japan. Among various other architectures, this studyproposes an approach of loitering dozens of micro-spacecraft in deep space, particularly in Earth-resonant flyby orbits, until a hazardous asteroid isdiscovered. In an Earth-resonant flyby orbit, the orbital period of the Earth and the spacecraft exhibit integer ratios, therefore allowing for repeatedEarth flybys.
Dozens of micro spacecraft are inserted into the Earth-resonant flyby orbit in our proposed mission architecture, with the advantage that eachspacecraft has the capability to perform an Earth flyby at a uniquely specified time. By making small trajectory correction maneuvers several weeksto a month before the Earth flyby, the spacecraft can drastically change its trajectory toward the target object utilizing the Earth's gravity assist. Forthis concept to work, at least one spacecraft would need to perform an Earth flyby on a month-to-month cadence; that is, this concept requires alarge-scale deep space constellation. This constellation can be built through rideshare opportunities to deep space or the Moon without the need fordedicated launch vehicles. Earth-resonant flyby orbits expand the reachable region with lower ΔV requirements because the spacecraft has a higherV-infinity with respect to the Earth than low-energy orbits, such as at Lagrange points. These high-energy loitering orbits improve the probability ofreaching interstellar objects and long-period comets.
This proposed mission architecture uniquely offers multiple flybys of NEOs while loitering in an Earth-resonant flyby orbit, as will be demonstrated byJAXA’s DESTINY+ mission. Via order of magnitude calculations, we estimate that ~5-10 NEOs can be directly explored every year if ~10 microspacecraft are deployed. The proposed multiple NEO flyby concept would bolster our collective planetary defense efforts while amplifying thescientific returns of in-situ exploration of this population. It would also solidify our overarching technology for asteroid flyby exploration.
This paper presents missionanalysis of reachable hazardous asteroids and configuration options for deep space constellations. We alsoinvestigate the example of multiple NEO flybys in the loitering orbit. Mission design results indicate the amount of required fuel that can be used toestimate the size of the spacecraft system.
Dozens of micro spacecraft are inserted into the Earth-resonant flyby orbit in our proposed mission architecture, with the advantage that eachspacecraft has the capability to perform an Earth flyby at a uniquely specified time. By making small trajectory correction maneuvers several weeksto a month before the Earth flyby, the spacecraft can drastically change its trajectory toward the target object utilizing the Earth's gravity assist. Forthis concept to work, at least one spacecraft would need to perform an Earth flyby on a month-to-month cadence; that is, this concept requires alarge-scale deep space constellation. This constellation can be built through rideshare opportunities to deep space or the Moon without the need fordedicated launch vehicles. Earth-resonant flyby orbits expand the reachable region with lower ΔV requirements because the spacecraft has a higherV-infinity with respect to the Earth than low-energy orbits, such as at Lagrange points. These high-energy loitering orbits improve the probability ofreaching interstellar objects and long-period comets.
This proposed mission architecture uniquely offers multiple flybys of NEOs while loitering in an Earth-resonant flyby orbit, as will be demonstrated byJAXA’s DESTINY+ mission. Via order of magnitude calculations, we estimate that ~5-10 NEOs can be directly explored every year if ~10 microspacecraft are deployed. The proposed multiple NEO flyby concept would bolster our collective planetary defense efforts while amplifying thescientific returns of in-situ exploration of this population. It would also solidify our overarching technology for asteroid flyby exploration.
This paper presents missionanalysis of reachable hazardous asteroids and configuration options for deep space constellations. We alsoinvestigate the example of multiple NEO flybys in the loitering orbit. Mission design results indicate the amount of required fuel that can be used toestimate the size of the spacecraft system.