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Photo solar eclipse from Chinese lunar satellite

Last Wednesday morning, July 3, the Dwingeloo Radio Telescope downloaded this eclipse photo from the Chinese lunar satellite DSLWP-B. The photo was taken on Tuesday evening, July 2, 2019, when a full solar eclipse was seen in South America. That is where the shadow of the Moon fell on Earth. That shadow is clearly visible in the photo.

The ISS and weather satellites have previously taken pictures of the shadow of the Moon on Earth, but this picture is – as far as we can ascertain – the first ever photograph of a solar eclipse taken from an orbit around the Moon. And the Dwingeloo Radio Telescope cooperated!

This year and last year many CAMRAS volunteers contributed to the collaboration in this special satellite webcam project from MingChuan Wei (BG2BHC/BY2HIT) of the Harbin Institute of Technology. A project that will end in the course of this month as the DSLWP-B satellite will crash onto the Moon in a controlled manner.

The CAMRAS-DSLWP-B team consisted of Cees Bassa, Paul Boven (PE1NUT), Tammo Jan Dijkema, Harry Keizer (PE1CHQ), Jan van Muijlwijk (PA3FXB) and André Offringa. Pieter-Tjerk de Boer (PA3FWM) and Simon Bijlsma (PA7SB) enabled streaming over WebSDR; Michel Roelofs (PA1MEF) made it possible to share raw data. In a broader scope, the team consists of the team at Harbin, specifically MingChuan Wei, and Reinhard Kühn (DK5LA) for uplink and Daniel Estévez (EA4GPZ/M0HXM) for analyses of the satellite orbit.

More info about this project in our blog posts Our precious Earth and the lunar far side, Time-laps of the Earth appearing behind the Moon and New photo of Lunar farside and Earth. Also, see our guest blog on The Planetary Society.

New photo of Lunar farside and Earth

On Monday 4th February 2019, the Dwingeloo telescope downloaded a new photo of Earth and the lunar farside. This photo, taken Sunday 3rd February 2019 at 15:20 UTC, shows the lunar farside and Earth (with South America in view). The lunar farside has more visible craters than the side of the Moon which faces Earth.

This photo was taken by the Chinese satellite LongJiang 2 in a lunar orbit. One of the devices on this satellite was made by students from the Chinese Harbin Institute of Technology. They put a (relatively) simple webcam on it that can take pictures on command. These photos are then sent to Earth with a little antenna. Because the satellite is so far away, receiving the signal requires a large radio antenna. The Chinese have asked the CAMRAS volunteers at the Dwingeloo Radio Telescope to help with this. Downloading this photo from the satellite to the Dwingeloo Telescope (16 KB in size) took 20 minutes.

The little Chinese satellite that took this photo has been in lunar orbit since the beginning of 2018. It ‘took a ride’ on the rocket that launched the bigger QueQiao satellite. That satellite also hosts antennas from ASTRON, the original owner and professional neighbour of the Dwingeloo Radio Telescope. ASTRON hopes to use the antennas on the big satellite to receive signals from just after the Big Bang as part of the Netherlands-China Low-frequency Explorer (NCLE) project.

The amateur radio payload that took this picture was developed at the Harbin Institute of Technology by Mingchuan Wei (BG2BHC), Hu Chaoran (BG2CRY), Tai Mier (KG5TEP), Zhao Yuhao (BG2DGR). Taking this photo was coordinated by Wei. While downloading this picture, the CAMRAS Dwingeloo Radio Telescope was operated by Cees Bassa, Tammo Jan Dijkema and Vanessa Moss. The commands were uplinked to the satellite by German radio amateur Reinhard Kuehn (DK5LA) with his home-built yagi array. See more details in blog post Our precious Earth and the lunar far side.

The photo has been color-corrected. Since the satellite camera lacks an infrared filter, colors come out too red. The original is below; we edited it to balance the colors, and make the Moon greyscale.

In October 2018, the Dwingeloo Telescope also cooperated in receiving a lunar farside photo (see blog post Our precious Earth and the lunar far side) and even a time-lapse showing the Earth disappear behind the Moon (see blog post Time-laps of the Earth appearing behind the Moon). At that time, the satellite was closer to the Moon, so the entire Moon did not fit in the picture. In the next months, we expect to receive more of these photos. But in August 2019, this adventure will end: then LongJiang 2 will crash in a controlled manner onto the lunar surface in a controlled manner. QueQiao will continue operating for the foreseeable future.