Small Innovative Missions for Planetary Exploration

Small Innovative Missions for Planetary Exploration (SIMPLEx) is a planetary exploration program operated by NASA. The program funds small, low-cost spacecraft for stand-alone planetary exploration missions. These spacecraft are intended to launch as secondary payloads on other missions and are riskier than Discovery or New Frontiers missions.^[1]

The LunaH-Map spacecraft

The program selects missions from multiple proposals and gives them some money to begin development. After early development they are analyzed to see if they are cost-effective and scientifically valuable during Key Decision Point-C. If they pass Key Decision Point-C then they move into full development. The missions must weigh less than 180 kg.^[2][3] So far only the first two missions have launched, and the remaining missions have struggled to stay within budget and find missions to launch with, and have been removed from multiple launches.

Missions

On August 8, 2015, the first two SIMPLEx missions were selected: Q-PACE and LunaH-Map.^[4] They were both CubeSats and each had a maximum budget of $5.6 million.^[5] Q-PACE launched on a Virgin Orbit LauncherOne as part of the ELaNa 20 mission. LunaH-Map is a 6U CubeSat that will map hydrogen on the Moon. The mission launched as a secondary payload on Artemis-1.^[6][7]

Three SIMPLEx-2 missions were selected in 2019. Janus was going to launch with Psyche and fly past multiple binary asteroid, but was removed from that mission due to the Psyche spacecraft being delayed. Lunar Trailblazer will launch with the IM-2 mission to study the Moon's geology and map its water.^[8] EscaPADE will send two small satellites to Mars to study its magnetosphere.^[2]

So far, only two missions in the SIMPLEx program have launched.

SIMPLEx missions

Name	Selection	Target	Launching with	Launch date
Q-PACE	SIMPLEx-1	Early protoplanetary disks	ELaNa Rideshare	17 January 2021
LunaH-Map	SIMPLEx-1	Moon	Artemis-1	16 November 2022
Janus	SIMPLEx-2	Binary asteroids	TBD	TBD
Lunar Trailblazer	SIMPLEx-2	Moon	IM-2	early 2024
EscaPADE	SIMPLEx-2	Mars	New Glenn^[9]	Late 2024

Q-PACE

Main article: Q-PACE

Q-PACE is a 3U CubeSat that would have studied the interactions of small particles in space in order to better understand early protoplanetary disks. The mission launched on January 17, 2021 on Virgin Orbit's LauncherOne as part of NASA's ELaNa program. Contact was never established with the CubeSat.^[10][11]

LunaH-Map

Main article: LunaH-Map

LunaH-Map (Lunar Polar Hydrogen Mapper) is a 6U CubeSat that was to map Hydrogen on the Moon using a neutron spectrometer. This mission launched as one of ten secondary payloads on Artemis 1. The mission was designed, built, and tested by Arizona State University. It would have take over a year for LunaH-Map to reach its science orbit, after which its 60-day science mission would begin.^[12][13] However, after it launched, the spacecraft ran into problems with its propulsion system.^[14]

 

Janus Artistic Rendering

Janus

Main article: Janus

Janus will send two small spacecraft to explore binary asteroids. The two spacecraft were scheduled to launch with Psyche on a Falcon Heavy rocket. The two identical spacecraft (Janus A and B) are being built by Lockheed Martin and are powered by solar panels and rechargeable batteries.^[15][16] The originally intended launch date for Psyche was August 1, 2022, but when that date was delayed to September 20, NASA had to replan the trajectories for the Janus spacecraft.^[17] The Psyche launch was then moved to October 2023, but this new launch date will not allow Janus to complete its mission, so Janus was removed from the Psyche launch plan.^[18]

Lunar Trailblazer

Main article: Lunar Trailblazer

Lunar Trailblazer will study water ice on the Moon and determine how it formed, how common it is, and where it is. The small spacecraft will be capable of looking inside permanently shadowed craters for water ice. The mission is managed by NASA's Jet Propulsion Laboratory.^[19][20] The spacecraft is scheduled to be completed in 2022 and will launch in early 2024 as a secondary payload on IM-2, Intuitive Machines' second lunar landing.^[21] The original plan was to launch Lunar Trailblazer as a secondary payload with the IMAP mission in 2025, but since the spacecraft would have been ready years before it was scheduled to launch, NASA found an earlier launch opportunity.^[10]

EscaPADE

Main article: EscaPADE

EscaPADE (Escape and Plasma Acceleration and Dynamics Explorers) will send two identical spacecraft to Mars. The spacecraft will be built by Rocket Lab and will be based on its Photon spacecraft bus. EscaPADE will study Mars' magnetosphere and how it has led to Mars' losing much of its atmosphere. The mission was originally going to launch with Janus and Psyche, but was removed from the Psyche launch manifest in 2020.^[22][23][24] On February 9, 2023, NASA announced that Blue Origin's New Glenn rocket would launch EscaPADE in late 2024. Eleven months after launch, EscaPADE will arrive at Mars. No other payloads were mentioned.^[9]

See also

• Discovery Program
• Explorers program

References

1. "NASA SOMA: SIMPLEx- Homepage". soma.larc.nasa.gov. Retrieved 2022-01-06.
2. Almeida, Andres (2019-06-19). "SIMPLEx Small Satellite Concept Finalists Target Moon, Mars and Beyond". NASA. Retrieved 2021-12-25.
3. "NASA selects planetary mission proposals large and small". SpaceNews. 2019-06-27. Retrieved 2022-01-12.
4. NASA, Small Innovative Missions for Planetary Exploration Program Abstracts of selected proposals, August 8, 2015. Retrieved Nov. 17, 2022.
5. "CubeSats to the Moon". The Planetary Society. Retrieved 2021-12-31.
6. "Explore Solar System and Beyond - PAC Meeting" (PDF). NASA. 1 March 2021. Retrieved 25 December 2021.
7. Blufish (2021-07-23). "ASU-led LunaH-Map spacecraft delivered to NASA's Kennedy Space Center". AZ Big Media. Retrieved 2022-01-12.
8. "NASA Confirms New SIMPLEx Mission Small Satellite to Blaze Trails Studying Lunar Surface". NASA Jet Propulsion Laboratory (JPL). Retrieved 2021-12-25.
9. Foust, Jeff (2023-02-10). "Blue Origin wins first NASA business for New Glenn". SpaceNews. Retrieved 2023-02-10.
10. "NASA looking for earlier launch of lunar orbiter smallsat mission". SpaceNews. 2021-03-26. Retrieved 2021-12-31.
11. "NASA - NSSDCA - Spacecraft - Details". nssdc.gsfc.nasa.gov. Retrieved 2021-12-31.
12. "LunaH-Map - Satellite Missions - eoPortal Directory". directory.eoportal.org. Retrieved 2021-12-31.
13. University, Arizona State. "LunaH-Map spacecraft safely delivered to NASA's Kennedy Space Center". phys.org. Retrieved 2022-01-03.
14. Mike Wall (2022-11-23). "Artemis 1 cubesat fails to fire engine as planned during moon flyby". Space.com. Retrieved 2022-11-28.
15. "NASA - NSSDCA - Spacecraft - Details". nssdc.gsfc.nasa.gov. Retrieved 2022-01-05.
16. Tomaswick, Andy. "NASA's Janus Mission is Going to Visit Two Binary Asteroids". Universe Today. Retrieved 5 January 2022.
17. "Psyche launch delay forcing revamp of rideshare mission". SpaceNews. 2022-06-09. Retrieved 2022-06-30.
18. "Janus Mission Removed from 2023 Psyche Launch Manifest – Janus". blogs.nasa.gov. Retrieved 2022-11-19.
19. NASA, Jet Propulsion Laboratory (2020-12-04). "Lunar Trailblazer: NASA Approves New Satellite to Map the Moon's Surface". SciTechDaily. Retrieved 2022-01-05.
20. "Lunar Trailblazer". trailblazer.caltech.edu. Retrieved 2022-01-05.
21. "NASA moves up Lunar Trailblazer launch". SpaceNews. 2022-06-22. Retrieved 2022-08-06.
22. "An ESCAPADE to Mars, on the cheap". The Planetary Society. Retrieved 2021-12-31.
23. "NASA's ESCAPADE Mission – Twin Martian Orbiters – Moves Toward Launch – ESCAPADE". blogs.nasa.gov. Retrieved 2021-12-25.
24. "NASA Mars smallsat mission passes review". SpaceNews. 2021-08-28. Retrieved 2021-12-30.