OMOTENASHI

OMOTENASHI (Outstanding MOon exploration TEchnologies demonstrated by NAno Semi-Hard Impactor) is a small spacecraft and semi-hard lander of the 6U CubeSat format that will demonstrate low-cost technology to land and explore the lunar surface. The CubeSat will also take measurements of the radiation environment near the Moon as well as on the lunar surface. Omotenashi is a Japanese word for "welcome" or "hospitality".^[1][4]

OMOTENASHI will be one of thirteen CubeSats to be carried with the Orion EM-1 mission into a heliocentric orbit in cislunar space on the maiden flight of the Space Launch System, scheduled to launch in December 2019.^[5]

Overview

The OMOTENASHI mission will land the smallest lunar lander to date on the lunar surface to demonstrate the feasibility of the hardware for distributed synergistic exploration system with multi-point exploration. Once on the lunar surface, the OMOTENASHI lander will observe the radiation environment of the lunar surface. The OMOTENASHI orbiter and lander were designed by the Japan Aerospace Exploration Agency (JAXA). It is a 6-Unit CubeSat measuring 10×20×30 cm, and has a mass of 14 kg (31 lb). The Principal investigator is Professor Tatsuaki Hashimoto from JAXA.^[6] The spacecraft features two deployable solar panels and lithium ion batteries. After measuring the radiation environment as it approaches the Moon, OMOTENASHI's lander module will perform a semi-hard landing on the lunar surface.^[7]

Payload

The lander's scientific payload consist on a radiation monitor and an accelerometer.^[1]

Propulsion and landing

OMOTENASHI uses a cold gas thruster to enter a lunar-impact orbit, and a solid rocket motor for the landing phase.^[3] The entry and landing phases will be informed by the use of an X band two-way Doppler.^[3] The orbiting module will enter at a shallow flight-path angle of ≤7 degrees, and it will be ejected when the solid rocket burn begins the deceleration maneuvre.^[3] The rocket will be ignited with a laser.^[1][8] After the deceleration rocket burn that will last 15-20 seconds,^[8] OMOTENASHI's lander will eject the retrorocket, experiencing a free-fall of about 100 m. Just before impact, the lander will deploy a single airbag about 50 cm in diameter to minimize the impact,^[8][9] estimated to be at 20 - 30 m/s.^[1][3]

See also

The 13 CubeSats flying in the Exploration Mission 1

• Lunar Flashlight will map exposed water ice on the Moon
• Near-Earth Asteroid Scout by NASA is a solar sail spacecraft that will encounter a near-Earth asteroid
• BioSentinel is an astrobiology mission
• SkyFire by Lockheed Martin
• Lunar IceCube, by the Morehead State University
• CubeSat for Solar Particles (CuSP)
• Lunar Polar Hydrogen Mapper (LunaH-Map), designed by the Arizona State University
• EQUULEUS, submitted by JAXA and the University of Tokyo
• OMOTENASHI, submitted by JAXA
• ArgoMoon, designed by Argotec and coordinated by Italian Space Agency
• Cislunar Explorers, Cornell University, Ithaca, New York
• Earth Escape Explorer (CU-E³), University of Colorado Boulder
• Team Miles, by Fluid and Reason LLC, Florida

References

External links

• An OMOTENASHI page, in Japanese but it includes interesting images.