HAKUTO-R Series 1

Mission specifications

Operator

ispace

Prime contractor

ispace

Launch

2022-12-11

Landing

2023-04-25

Landing site

Atlas crater, Mare Frigoris (planned; impacted at altitude ~5 km)

Customer

private

Payload

Rashid rover (10 kg, UAE/MBRSC) + Sora-Q (0.25 kg, JAXA) + commercialas of 2023-04-25^[1]

Key findings

• 1.Launched 11 Dec 2022 on a Falcon 9 and reached lunar orbit on 21 Mar 2023; by mid-April it had completed all planned orbital-control maneuvers, sitting in an elliptical orbit (~100 km at perilune, ~2,300 km at apolune) — 8 of ispace's 10 pre-defined mission milestones (the final two, landing and post-landing stability, were never reached).
• 2.Travelled roughly 1.4 million km on a low-energy transfer — at the time, the furthest any privately funded spacecraft had flown.
• 3.During the 25 Apr 2023 descent, the lander crossed the ~3 km-high rim of a crater; the onboard software read the sudden altitude jump as a fault and began disregarding the (correct) radar altimeter data.
• 4.Misjudging its true height, the lander hovered ~5 km above the surface until its propellant was exhausted, then free-fell and crashed near Atlas crater in Mare Frigoris.
• 5.Carried the 10 kg Emirates 'Rashid' rover (MBRSC/UAE) and JAXA/Tomy's transformable 'Sora-Q' robot, both lost in the crash; NASA's Lunar Reconnaissance Orbiter located the impact debris on 23 May 2023.

Mission outcome

HAKUTO-R Mission 1 was the first landing attempt by Japan's ispace and the first by a commercial lunar lander of its generation, and although it reached lunar orbit and cleared 8 of its 10 milestones, it crashed during the final descent on 25 April 2023. ispace traced the failure to a software logic flaw: after the lander passed over a tall crater rim, the flight computer treated the abrupt altimeter reading as an error and ignored it, leaving the craft to run out of fuel while hovering roughly 5 km up before free-falling near Atlas crater in Mare Frigoris. Despite ending in failure, the mission flew further than any privately funded spacecraft had before it and yielded the engineering lessons that shaped ispace's subsequent flights.