Tag: SLIM

After a few days of wakefulness, Japan’s SLIM moon lander has gone dormant once more at the start of a 14-day-long lunar night.

The upended robot sent back a stream of data and imagery while its solar cells were in position to soak up sunlight, and its handlers hope they can get SLIM to wake up again and resume its work after lunar sunrise in mid-February.

The car-sized robot accomplished its primary mission on Jan. 20 (Japan time) when it landed within 100 meters of its target point near Shioli Crater. SLIM — which is an acronym standing for “Smart Lander for Investigating Moon” — was designed to demonstrate a precision landing technique that Japan hopes to use for future missions to the moon and Mars.

Unfortunately, the lander ended up in an upside-down position, with its solar cells pointing off to the side. Mission managers were able to get some data and pictures back — including a photo captured by a mini-robot that documented the lander’s predicament. But within hours, the lander’s batteries ran down to the point that SLIM had to go into hibernation. The mission team could only hope that as the sun moved westward in the lunar sky, enough light would eventually hit the panels to allow for a reawakening.

That’s exactly what happened on Jan. 28: The Japan Aerospace Exploration Agency, a.k.a. JAXA, re-established contact with the charged-up SLIM and commanded the lander to transmit a set of multispectral images showing the area around the landing site — including a variety of rocks named after canine breeds, such as Bulldog, Toy Poodle and Aki Inu.

Update for Jan. 30: The sideways solar cells on Japan’s SLIM moon lander soaked up enough sunlight to allow for the robot’s revival on Jan. 28. SLIM is gathering up science data, including a closeup image of a lunar rock called Toy Poodle, but the power drain is expected to resume Feb. 1 when the 14-day-long lunar night begins.

Now we know why Japan’s lunar lander wasn’t able to recharge its batteries after touching down on the moon last week: The spacecraft appears to have tumbled onto its side, with its solar cells facing away from the sun.

The good news is that the Smart Lander for Investigating Moon, or SLIM, achieved its primary mission of setting down within 100 meters (330 feet) of its target point — and that the mission’s two mini-probes, which were ejected during SLIM’s descent, are working as intended.

Scores of images were taken before and after landing. One of the pictures. captured by a camera on the ball-shaped LEV-2 mini-probe, shows the lander sitting at an odd angle with its thrusters facing upward and its solar cells facing westward.

To conserve battery power, mission managers at the Japan Aerospace Exploration Agency shut down SLIM after the probes transmitted the imagery they collected. But there’s still a chance that the sun’s shifting rays could provide enough power to allow for further operations in the week ahead.

Update for Jan. 21: The Japan Aerospace Exploration Agency said it shut down its moon lander to conserve battery power, but added that the lander might be recharged and revived if sunlight hits the spacecraft’s solar cells at the right angle.

Japan has become the fifth nation to land a functioning robot on the moon, but the mission could fall short of complete success due to a problem with the lander’s power-generating solar cells.

The Smart Lander for Investigating Moon, or SLIM, was launched along with an X-ray space telescope called XRISM from Japan’s Tanegashima Space Center in early September — and after weeks of in-space maneuvers, SLIM touched down today at 1520 GMT (7:20 a.m. PT Jan. 19, or 12:20 a.m. JST Jan. 20).

The Japan Aerospace Exploration Agency reported that the landing was successful. During a news briefing, Hiroshi Kuninaka, director general of JAXA’s Institute of Space and Astronautical Science, said the achievement marked “a major milestone” in Japan’s effort to send spacecraft to the moon, and eventually to Mars.

Kuninaka said SLIM was able to communicate with Earth and respond to commands. “However, it seems that the solar cells are not generating electricity at this point in time,” he said. “And since we are not able to generate electricity, the operation is being done using batteries alone.”