15:45 〜 16:00
[PPS04-02] Phantom: An Aerobot Mission to the Skies of Venus
★Invited Papers
キーワード：Venus, Habitability, Aerial Platform, Aerobot, Balloon, New Frontiers
Introduction: The selection in 2021 of the VERITAS, DAVINCI, and EnVision missions heralded the start of a new era of Venus exploration. But even with these missions, there remains an enormous amount we have yet to learn about Venus—including science questions that require atmospheric data taken at multiple latitudes, longitudes, and altitudes, or measurements taken on or of the surface at individual sites or at larger spatial scales.
The Phantom Mission: Phantom is an ambitious New Frontiers-class (~US$1B) mission concept under development at the Jet Propulsion Laboratory, and features an aerial robot (aerobot) paired with an orbiter to address these and other science objectives from within the Venus clouds (image, left).
The Phantom aerobot is a variable-altitude balloon and gondola able to traverse an altitude range of 52–62 km with an instrument payload of ~25 kg. Operating in the middle cloud layer and requiring materials and construction methods to resist the high-acidity environment, the aerobot circumnavigates Venus in 5–7 Earth days1. To minimize battery power consumption, most science operations will be performed on the day side where solar power is available; the nominal lifetime of the balloon exceeds 30 Earth days.
Supporting the operations of the aerobot is an orbiter that also carries a science payload. The orbiter will assume an inclined, elliptical orbit about Venus to permit synoptic imaging of the Venus atmosphere, serve as a communications relay to Earth, and track the aerobot. The orbiter’s lifetime is measured in years, offering continued valuable science at Venus long after the aerobot phase of the mission ends, and operating as a radio relay for subsequent aerial and lander missions.
Mission Theme and Science Objectives: Taking as its core science focus the theme of “volatiles,” Phantom has seven primary science objectives:
1) Establish if the Venus clouds are habitable2;
2) Characterize the nature of aerosols there2;
3) Determine how volatiles are transported to, in, and through the cloud layer;
4) Ascertain how radiative flux drives convection, circulation, and microphysics in the Venus atmosphere;
5) Search for a modern magnetic field or evidence for an ancient record of intrinsic Venus magnetism;
6) Test whether volcanic eruptions inject volatiles into the atmosphere3; and
7) Establish the atmospheric species lost to space.
Technology Development: Although the middle Venus atmosphere is a far more benign environment than the surface, key technical challenges persist. For instance, the Venus clouds are primarily composed of sulfuric acid droplets, requiring the use of acid-resistant materials on the outer balloon envelope, gondola, and solar panels. Further, given the science requirement to take measurements across a range of altitudes, the Phantom aerobot features an outer, metallized, unpressurized balloon that is coated in Teflon, which protects against sulfuric acid cloud droplets and sunlight, and which encompasses an inner, super-pressure balloon reinforced with Vectran; exchanging helium between the inner and outer balloons modulates the aerobot’s buoyancy and thus altitude1.
A one-third-scale aerobot prototype successfully demonstrated this design during test flights in Black Rock Desert, Nevada in July 2022 (image, right). These tests validated the use of variable-altitude balloon technology in temperature–pressure conditions similar to those the full-scale aerobot would encounter in the middle Venus atmosphere, and provided crucial flight data for simulation models of full-scale aerobot operations at Venus1. Work continues to develop ever-higher-fidelity balloons with materials and seams able to withstand the temperatures, pressure loads, sulfuric-acid concentrations, and solar radiative heating conditions that characterize the Venus clouds.
References: 1Izraelevitz, J. S., et al. (2023) JpGU, this mtg. 2Baines, K. H., et al. (2023) JpGU, this mtg. 3Cutts, J. A., et al. (2023) JpGU, this mtg.
The Phantom Mission: Phantom is an ambitious New Frontiers-class (~US$1B) mission concept under development at the Jet Propulsion Laboratory, and features an aerial robot (aerobot) paired with an orbiter to address these and other science objectives from within the Venus clouds (image, left).
The Phantom aerobot is a variable-altitude balloon and gondola able to traverse an altitude range of 52–62 km with an instrument payload of ~25 kg. Operating in the middle cloud layer and requiring materials and construction methods to resist the high-acidity environment, the aerobot circumnavigates Venus in 5–7 Earth days1. To minimize battery power consumption, most science operations will be performed on the day side where solar power is available; the nominal lifetime of the balloon exceeds 30 Earth days.
Supporting the operations of the aerobot is an orbiter that also carries a science payload. The orbiter will assume an inclined, elliptical orbit about Venus to permit synoptic imaging of the Venus atmosphere, serve as a communications relay to Earth, and track the aerobot. The orbiter’s lifetime is measured in years, offering continued valuable science at Venus long after the aerobot phase of the mission ends, and operating as a radio relay for subsequent aerial and lander missions.
Mission Theme and Science Objectives: Taking as its core science focus the theme of “volatiles,” Phantom has seven primary science objectives:
1) Establish if the Venus clouds are habitable2;
2) Characterize the nature of aerosols there2;
3) Determine how volatiles are transported to, in, and through the cloud layer;
4) Ascertain how radiative flux drives convection, circulation, and microphysics in the Venus atmosphere;
5) Search for a modern magnetic field or evidence for an ancient record of intrinsic Venus magnetism;
6) Test whether volcanic eruptions inject volatiles into the atmosphere3; and
7) Establish the atmospheric species lost to space.
Technology Development: Although the middle Venus atmosphere is a far more benign environment than the surface, key technical challenges persist. For instance, the Venus clouds are primarily composed of sulfuric acid droplets, requiring the use of acid-resistant materials on the outer balloon envelope, gondola, and solar panels. Further, given the science requirement to take measurements across a range of altitudes, the Phantom aerobot features an outer, metallized, unpressurized balloon that is coated in Teflon, which protects against sulfuric acid cloud droplets and sunlight, and which encompasses an inner, super-pressure balloon reinforced with Vectran; exchanging helium between the inner and outer balloons modulates the aerobot’s buoyancy and thus altitude1.
A one-third-scale aerobot prototype successfully demonstrated this design during test flights in Black Rock Desert, Nevada in July 2022 (image, right). These tests validated the use of variable-altitude balloon technology in temperature–pressure conditions similar to those the full-scale aerobot would encounter in the middle Venus atmosphere, and provided crucial flight data for simulation models of full-scale aerobot operations at Venus1. Work continues to develop ever-higher-fidelity balloons with materials and seams able to withstand the temperatures, pressure loads, sulfuric-acid concentrations, and solar radiative heating conditions that characterize the Venus clouds.
References: 1Izraelevitz, J. S., et al. (2023) JpGU, this mtg. 2Baines, K. H., et al. (2023) JpGU, this mtg. 3Cutts, J. A., et al. (2023) JpGU, this mtg.