Chang'e 5 test vehicle maps future sample return site
Posted by Emily Lakdawalla
03-09-2015 12:13 CDT
This summer the Chinese space agency has been making progress toward its planned 2017 launch of the Chang'e 5 robotic sample return mission, performing low-altitude imaging of the future landing site. According to an article from the China News Network, the Chang'e 5 test vehicle performed the imaging campaign between August 30 and September 2 from an altitude of 30 kilometers above the lunar nearside. Thanks to Quanzhi Ye for translating the text for me.
It's not clear where on the Moon this is, or what the scale of the image is. Planetary cartographer extraordinaire Phil Stooke attempted to narrow it down from the lengths of the shadows in the craters: "The terminator was crossing the Mare Crisium area over the few days the images were taken. I had been expecting a landing in Oceanus Procellarum, but the sun would have been overhead there, and these images have shadows suggesting a lower sun elevation. Possibly a site in the eastern maria, but west of Crisium. Not much to go on yet."
When I first read this news I was terribly confused because I thought that I'd heard that they had planned a landing on the farside. But I was recalling the wrong mission. It's Chang'e 4 -- the backup module to Chang'e 3 -- that is planned for a future landing on the lunar farside. That launch is not planned until around 2020. In case you are as confused as I was, here's a brief summary of the Chang'e program:
- Chang'e 1 (launched 2007) was a lunar orbiter. It impacted the Moon in 2009.
- Chang'e 2 (launched 2010) was the engineering backup to Chang'e 1. It orbited the Moon and then flew past asteroid Toutatis in 2012. As far as I know, it is still active, in solar orbit. (EDIT: According to this article, Chang'e 2 is not currently in contact with Earth, perhaps because it is too far away; it is expected to return to the vicinity of Earth in 2020. Thanks to Quanzhi Ye for the link.)
- Chang'e 3 (launched 2013) is a lunar lander that carried the Yutu rover to the Moon. Both are still active on the lunar surface.
- Chang'e 5 test vehicle, also called Chang'e 5 T1 (launched 2014) is an engineering test mission consisting of a Chang'e 2-like service module that carried a test sample return module to the Moon and returned it to Earth. It has since traveled to the Earth-Moon L2 point and returned. The service module is still in lunar orbit, now mapping landing sites for Chang'e 5.
- Chang'e 5 (to launch in 2017) will be a robotic sample return mission, landing on the lunar nearside.
- Chang'e 4 (to launch around 2020) was the engineering backup to the Chang'e 3 lander. It will likely be sent to the lunar farside.
- Chang'e 6 is only a rumor at present, but it's very likely that, as with all previous missions, there will be a duplicate Chang'e 5 robotic sample return spacecraft built that could be launched later.