LunaH-Map ( Lunar Polar Hydrogen Mapper Mission)

Map the hydrogen content of the entire South Pole of the moon, including within permanently shadowed regions at high resolution.

Map the hydrogen content of the entire South Pole of the moon, including within permanently shadowed regions at high resolution. Measure the bulk hydrogen content, up to a meter beneath the lunar surface, while the instruments on both Lunar IceCube and FLASHLIGHT will tell us about the very top few microns. Create the high-resolution maps of regional near-surface (top-meter) water-ice distribution across the entire South Pole of the moon.

On Nov. 28, NASA’s LunaH-Map spacecraft acquired its first star tracker image, showing the constellation Auriga and its two brightest stars, Menkalinan and Mahasim.

The mission team also made several attempts to image the Earth and Moon; however, these images resulted in saturation of the star tracker. In the coming weeks, additional imaging opportunities of the Earth and Moon will be evaluated to help further demonstrate these novel autonavigation capabilities.

While a recent telemetry downlink showed an unexpected spacecraft reset, a Deep Space Network (DSN) pass has since indicated that, with the exception of the likely stuck propulsion system valve, the spacecraft is healthy with all subsystems nominal and operating as expected.

The problem instead was with the cubesat’s propulsion system, an electric thruster called BIT-3 from Busek that uses solid iodine as propellant. The thruster did not operate as expected in the days after launch, causing the spacecraft to miss its primary opportunity to maneuver into orbit around the moon.

Propulsion system (Busek ion thruster) unable to activate; missed LOI; losing link margin; using DSN arrays to close link.

LunaH-Map Mission Status (Interplanetary Small Satellite Conference 2023):

• Batteries at 70% SOC on deployment (consistent with optimistic predicts from lab data).
• All spacecraft systems were commissioned successfully.
• Neutron data were collected early after deployment.
• Reaction wheel speeds are being managed via reorienting the spacecraft.
• Successfully acquired star field and planet images with star tracker.
• Propulsion system did not ignite after initial attempts prior to the lunar flyby:
  • This was not unexpected given the long wait after spacecraft delivery to launch (over a year) ß more on this later.
  • Doppler ranging data showed detectable spacecraft motion during ignition attempts, and reaction wheel speeds change in directions consistent with minor amount of iodine flow. This suggests a partially stuck valve.
  • The propulsion system has heaters to condition the valve to unstick, however, to date attempts at raising tank and valve temperatures have been unsuccessful.
  • EOM will be end of May 2023 unless ignition is achieved.
  • Contacts 2X per week continue to attempt ignition.

• AVIONICS - Blue Canyon XB1
• THRUSTER - Busek BIT-3
• TRANSCEIVER - JPL Iris Deep Space Transponder
• SOLAR PANELS - MMA Design eHaWK

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