China lands Chang'e-4 on far side of Moon

Post by rsynnott » Thu, Jan 03, 2019, 1:40 PM UTC

A2017U1 wrote: post #4

Copying earlier comment: Wikipedia seems to say the rover mission duration is 3 months, yet the previous rover traveled for a year and transmitted a bit longer. The Chinese seemed quite coy about it failing last time (as with many things) so perhaps underpromising in this case? This all preparation for China's planned permanent radio telescope on the far side which would be a huge boon for astronomers by escaping Ear…

Post by hanoz » Thu, Jan 03, 2019, 1:46 PM UTC

Symmetry wrote: post #96

0nce wrote: post #61

Earlier quoted context omitted.

Lagrange points are found near any couple of large bodies. They are points where a smaller object will maintain its position relative to the large orbiting bodies. The Chinese relay satellite is orbiting the L2 point of the Earth-Moon system. That is beyond the Moon on a line which goes from Earth to Moon. Hence, this L2 point orbits the Earth like the Moon does, and the whole system orbits the Sun as well. Now if th…

I just wanted to add that L2 (and L1 and L3) are unstable in that if a satellite is a bit further than the exact point it will tend to get ever further with time and a satellite that's closer will tend to get even closer. But the closer you are to the exact L2 point the smaller these tendencies are and the amount of fuel needed to remain on station is minimal, a satellite will just eventually run out some day and fal…

Post by betterworldb » Thu, Jan 03, 2019, 1:52 PM UTC

DoreenMichele wrote: post #80

China releases photos from first-ever mission to land on the dark side of the moon https://www.businessinsider.com/photos-dark-side-moon-china-...

Post by Serthys » Thu, Jan 03, 2019, 2:05 PM UTC

betterworldb wrote: post #105

DoreenMichele wrote: post #80

China releases photos from first-ever mission to land on the dark side of the moon https://www.businessinsider.com/photos-dark-side-moon-china-...

Is there a way around the paywall for business insider?

Post by paraditedc » Thu, Jan 03, 2019, 2:16 PM UTC

DoreenMichele wrote: post #106

betterworldb wrote: post #105

Earlier quoted context omitted.

Is there a way around the paywall for business insider?

The photos were originally published here: http://www.cnsa.gov.cn/n6758823/n6758838/c6805034/content.ht... It's the original source. I chose to post the BI article because the original source is in Chinese.