Thursday, January 3, 2019

Congratulations to the China National Space Agency

        Chang'e 4 touched down on the floor of Von Kármán crater at 02:26 GMT today. This is the first image from the lander:

photo: CNSA

        There is no direct communication between Earth and Chang'e 4. Data is relayed via a satellite called Queqiao (trans: Magpie bridge) at the L2 libration point, 64,000 km beyond the Moon. Queqiao was pre-positioned in May last year. I don't know whether the relay has spare channels that might be available to other nations' far side landers, if and when they arrive.

        Von Kármán is an enormous crater, whose Eastern edge is right on the 180° longitude. The cross marks the exact landing point, 45.471° S 177.606° E.

        Here's where it is in relation to the whole far side. The very large dark area at 26.5° N, 148° E is the Mare Moscoviense, one of the very few maria on this side of the Moon. Tsiolkovsky, the crater that Ken Johnston says contains an alien base, is also notably dark, at 20.4° S, 129.1° E (almost due NW from Von Kármán). The so-called "crashed spaceship" visited by the non-existent Apollo 20 mission is at 18.66° S, 117.68° E; NW again from Tsiolkovsky and well over toward the near side.


Trivia: The crater is named for Theodore Von Kármán (born Kármán Tódor in Budapest), a mathematician and aeronautical engineer who was one of the founders of JPL. The public auditorium at JPL is also named for him.

Update 4 January:

photo: CNSA

        This is how far the Yutu rover has progressed. It will now go into sleep mode for six days to assure survival during the hottest part of the lunar day.

Update 11 January:
The real-time descent and landing video is now available.


Chris said...

Well done China, the first step to a lunar-based radio telescope!

Trekker said...

And of course, the dimwits are already out in force on various comments sections, either denying it outright, wondering what's lighting the scene as it's on the 'dark' side, or asking if it's not going to check on the Apollo landing 'site' (singular) to see if the flag is there or not. You can't fix stupid.

THE Orbs Whiperer said...

I have a funny, feeling about this. Today started out unusual for me from the beginning. If there were to be a military base established on the far side, it would be out of direct line of attack from Earth, yet a boulder could be rolled off the edge to land on US.

Bill said...

This is great news, I hope more pics and even video can be sent soon.

SpaceJames said...

Yutu 2 has begun its journey.

Trekker said...

"a boulder could be rolled off the edge to land on US."


Anonymous said...

Boulder "rolled off the edge..."??? Serious suggestion: Get a book on orbital dynamics. Rolled off the edge indeed...

OneBigMonkey said...

Your estimate is slightly out.

I overlaid the last image released from the descent camera on the LRO map and got this:

The centre of that image is marked on this image:

and the coordinates there are -45.4564, 177.5963

The image is still roughly 3.25 km across at that point, so there is still some distance to go. The elongation of the overlay suggests that the camera is at a slight angle, so the actual landing spot will be somewhere west of that point, but not by much :)

OneBigMonkey said...

..and as an addendum to my previous post, I found a video source which zooms in closer than the photo I grabbed from the CNSA webasite. Overlaying that shows that they were definitely homing in on the area in the centre of the image I posted previously.

This time the image covers an area around 1.25km across.

expat said...

I thought Theadora's "boulder rolled off the edge" would amuse people, I allowed it to publish just for a giggle.

Thanks Monkey and SpaceJames. I've added some text but not edited my image.

Aleck Schmart said...

In the low gravity environment of, Earth's Moon, a boulder large enough to devastate the planet, could easily be projected off the surface of the Moon, and the Earth's gravity would draw it down at sufficiently, high velocity to simulate an asteroid impact.

This scenario is presented in the novel, "The Moon Is A Harsh Mistress".

Trekker said...

Space James, I'm surprised at the poor quality of that photo. Is that the best we're going to see?

expat said...

« a boulder large enough to devastate the planet, could easily be projected off the surface of the Moon »

Easily? The escape velocity is 8,568 km/hr. It'd take quite some energy to accelerate your big boulder that much.

expat said...

The grumpy old men over at The Hidden Mission aren't impressed, apparently. Keith Laney posted "chinese space craft = junk. how long did their last little moon rover last?
they're going to be the first freeze dried people on the moon in a loong time. people wow about china doing something... like they'll be any better or open than anyone else... nope!
We have private companies that will beat China to the moon with men."

Vianova wrote "Lots of expendable Chinese taikonauts ready to die in punk-ass Chinese spacecraft. Trash cans with rocket propellant, and limpy gimpy rovers."

Some people are just hard to please (Also remarkably ignorant).

expat said...

BTW the answer to Keith's question is 31 months, cf. 3 months expected life. The rover could not move after its second lunar night but continued to gather and transmit useful data.

Aleck Schmart said...

Are you saying that the Chinese are too, weeny to be able to launch a, goddess of liberty statue, off the Moon?

expat said...

Landing site pic updated.

SpaceJames said...

@Trekker - There is speculation among Chinese rocket spotters that CNSA will release high quality images and video. Everything I have seen comes from

Trekker said...

Space James - that's good to know. The poor quality of the first images just adds fuel to the deniers' claims of fraud and fakery.

Merv Ritchie said...

Wow, congratulations to the Peoples Republic of China and the Chairman.

This is a remarkable achievement. As respectable a world citizen as the Chinese Nation is the world as a whole is better off today than it was previously.

Maybe they will bring greater peace to the world as our western culture has only brought conflagration.

Welcome to Space China!

OneBigMonkey said...

CNSA are being pretty good at posting updates:

I believe they will eventually release everything - their entire image collection from the previous 3 successful lunar missions are all available on their website here:

You need to register to download but it's not caused me any issues.

though they may take their sweet time about it if previous experience is anything to go by. their images from CE-2 are extremely good.

Two Percent said...

FWIW, the BBC has a different pic:

Not sure what the ghost is under the LH solar panel.


OneBigMonkey said...

I've been looking at other data sources for the crater and have come up with this from Japan's Kaguya 3D data.

The yellow dot marks the landing site, and the hills in the distance are about 10 km away and are what I believe can be seen in the background of the lander images. The vertical has been exaggerated to make them stand out more.

OneBigMonkey said...

I have to withdraw my previous estimate of what we were looking at!

As someone pointed out on a forum I post in, those hills are insignificant, and we are suffering from the 'small, far away' problem! On checking the shadow direction on the rover, it seems we are looking south, so I had another look and came up with this:

The image is rotated 180 degrees so South is at the top. The coordinates of the crater I picked out with the red arrow are -46.8049 178.3877

expat said...

Thanks guys.

jim oberg said...

Some background on the target region, one of the most interesting scientific AND resource-utilization regions on the moon, as scientists realized years ago ==
Aitken Basin mission, “Astronomy” magazine, Dec 2005

Chris said...

Scott Manley has a nice video studying the landing in detail, comparing it with images of the moon.