ispace HAKUTO-R Mission 1 (private Moon lander)

[JMCx4]

ispace HAKUTO-R Mission 1: Landing Live Stream​

Landing very soon.

Click to read more...

 

[JMCx4]

Update: The stream has ended. The Mission Team did capture lunar lander telemetry data during the landing phase, but has since lost comms with the lander. Lots of apologies from official-looking people.

ETA: The Mission 1 webpage for background info.

 

[JMCx4]

NY Times article, posted after ispace went silent (just like their lander did) ... What may have been lost if the Hakuto-R moon lander crashed

ETA: Here is a link to the free-to-read DNYUZ.com copy of the get-on-our-list NYT article linked above.

 

[JMCx4]

Mission 1 Update ...

Based on the currently available data, the HAKUTO-R Mission Control Center in Nihonbashi, Tokyo, confirmed that the lander was in a vertical position as it carried out the final approach to the lunar surface. Shortly after the scheduled landing time, no data was received indicating a touchdown. ispace engineers monitored the estimated remaining propellant reached at the lower threshold and shortly afterward the descent speed rapidly increased. After that, the communication loss happened. Based on this, it has been determined that there is a high probability that the lander eventually made a hard landing on the Moon’s surface. ...

 

[JMCx4]

NASA's Lunar Reconnaissance Orbiter identified evidence of wreckage from the ispace HAKUTO-R Mission 1 lander ...

... On 26 April 2023, the Lunar Reconnaissance Orbiter (LRO) spacecraft acquired ten images around the landing site with the Narrow Angle Cameras (NACs). The images covered a region roughly 40 km by 45 km. Using a NAC image acquired before the landing attempt, the Lunar Reconnaissance Orbiter Camera (LROC) science team began searching for the lander. ...

From the temporal image pair, the LROC team identified an unusual surface change near the nominal landing site. The image shows at least four prominent pieces of debris and several small changes (47.581°N, 44.094°E). The central feature in the image above shows several bright pixels in the upper left and serval dark pixels in the lower right. This is the opposite of nearby boulders, suggesting this could be a small crater or different parts of the lander body. This site will be analyzed more over the coming months as LROC has the opportunity to reimage the site under various lighting and viewing geometries. ...

Ratio image created by dividing the after (M1437131607R) and before (M192675639R) images. The impact created an area of higher reflectance, approximately 60-80 m across [NASA/GSFC/Arizona State University].


See more imagery at: Impact Site of the HAKUTO-R Mission 1 Lunar Lander

 

[JMCx4]

See, it's ALWAYS the software's fault ...

ispace-inc.com > News

ispace Announces Results of the "HAKUTO-R" Mission 1 Lunar Landing​

26 May, 2023

Landing Anomaly Identified for Future Mission Improvements

TOKYO—May 26, 2023—ispace, inc., (ispace) a global lunar exploration company, announced today that it has reviewed and completed the analysis of the flight data from its HAKUTO-R Mission 1 landing sequence on April 26, 2023. The flight data was obtained by operations specialists at ispace’s Mission Control Center in Nihonbashi, Tokyo.

The analysis reveals that the lander fully completed the entire planned deceleration process, slowing to the target speed of less than 1 m/s in a vertical position at an altitude of approximately 5 kms above the lunar surface. ...

On April 26, 2023, at 00:40 Japan Standard Time, the lander began the descent sequence from an altitude of approximately 100 kms above the lunar surface. At the end of the planned landing sequence, it approached the lunar surface at a speed of less than 1 m/s. The operation was confirmed to have been in accordance with expectations until about 1:43 a.m., which was the scheduled landing time.

During the period of descent, an unexpected behavior occurred with the lander’s altitude measurement. While the lander estimated its own altitude to be zero, or on the lunar surface, it was later determined to be at an altitude of approximately 5 kms above the lunar surface. After reaching the scheduled landing time, the lander continued to descend at a low speed until the propulsion system ran out of fuel. At that time, the controlled descent of the lander ceased, and it is believed to have free-fallen to the Moon’s surface.

The most likely reason for the lander’s incorrect altitude estimation was that the software did not perform as expected. Based on the review of the flight data, it was observed that, as the lander was navigating to the planned landing site, the altitude measured by the onboard sensors rose sharply when it passed over a large cliff approximately 3 kms in elevation on the lunar surface, which was determined to be the rim of a crater. According to the analysis of the flight data, a larger-than-expected discrepancy occurred between the measured altitude value and the estimated altitude value set in advance. The onboard software determined in error that the cause of this discrepancy was an abnormal value reported by the sensor, and thereafter the altitude data measured by the sensor was intercepted. This filter function, designed to reject an altitude measurement having a large gap from the lander’s estimation, was included as a robust measure to maintain stable operation of the lander in the event of a hardware issue including an incorrect altitude measurement by the sensor.

One major contributing factor to this design issue was a decision to modify the landing site after critical design review completed in February 2021. This modification influenced the verification and validation plan despite numerous landing simulations carried out before the landing. ispace as the mission operator maintained overall program management responsibility and took into account the modifications in its overall analysis related to completing a successful mission. It was determined that prior simulations of the landing sequence did not adequately incorporate the lunar environment on the navigation route resulting in the software misjudging the lander’s altitude on final approach. ...

 

[hatterson]

Scott Manley details the bug in an easy to understand way for those interested.