Imaging the Earth and the far side of the moon from Lunar orbit

The Moon and Earth

Via the Planetary Society blog:

Earlier this week, on October 10, radio amateurs all around the world worked together to get the Chinese Longjiang-2 spacecraft to take an image of the Earth and the far side of the Moon.

Radio commands were generated by MingChuan Wei in China, transmitted to the spacecraft by Reinhard Kuehn in Germany after which they were received by the spacecraft in lunar orbit.

In turn, the spacecraft transmitted the image back to Earth, where it was picked up by radio amateurs in Germany, Latvia, North America and the Netherlands.

This image represents the culmination of several observing sessions spread over the past few months where we used the Dwingeloo telescope in collaboration with the Chinese team from Harbin University of Technology, who build the radio transceiver on board Longjiang-2, and radio amateurs spread across the globe.

During these sessions, the team tested receiving telemetry through low-bit rate and error-resistant digitally modulated transmissions, as well as the JT4G modulation scheme designed by radio amateur and Nobel prize winning astrophysicist Joe Taylor (K1JT) for weak signal Moon bounce experiments. Besides telemetry, they performed a VLBI experiment by simultaneously observing Longjiang-2 from China and Dwingeloo, and also downloaded images taken by Longjiang-2 of the lunar surface, lens flares, and the starry sky as seen from lunar orbit.

After a radio-quiet period to avoid interfering with the Chang’e 4 Lunar landing, DSLWP-B became active again on 13 January 2019. The first opportunity to take photos of Earth and Moon were on 3 February, on which a command was sent to take another timelapse. The first image from this timelapse was downloaded with the Dwingeloo telescope on February 4, 2019. For the first time, it the entire Moon and Earth are in view (above).

Read directly from the team’s post on camras.nl.