Reception of the American Moon lander IM-1

On 22 February (UTC), the American spacecraft NOVA-C/IM-1 landed on the Moon. We received its signals with the radio telescope and tracked its progress through their Doppler shift. Our reception was streamed to Youtube, where apparently also from the IM-1 team followed them.

During the landing the signal got very weak, presumably because the antennas on the spacecraft were not directed to Earth. Also after the landing, the signal was only barely visible with our 25 meter dish. The current thinking is that IM-1 tipped over after landing, causing the antennas not to point to Earth.

The signal during and after landing was so weak, that it was almost invisible in our live stream. However, after integrating the signal a bit more and stretching the color scale, one can see the effect of the landing burn on the Doppler shift of the signals.

During the evening of the landing, we had to temporarily stop tracking the Moon due to a storm. Luckily the storm passed before the actual landing, and we could point the telescope at the Moon again.

On 21 February, the day before the landing, the spacecraft performed its Lunar Orbit Insertion Burn. We tracked this maneuver and streamed it. We could see that the maneuver took place exactly at the announced times.

Last month, we also tracked the successful Japanese Moon landing of SLIM. We were one of the two station on Earth to receive UHF signals from LEV-1, the moon ‘hopper’. Other Moon landing attempts we tracked with the Dwingeloo telescope were those of Beresheet (Israel) and Chandrayaan-2 (India) in 2019. In 2022, we tracked the American mission Artemis-1 for a month in an official collaboration with NASA.