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

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

#181

Post by swampthing »

stcredzero wrote: post #161
arduanika wrote: post #5

"...and if the dam breaks open many years too soon..." Perhaps interesting to note the origin of this name for spacecraft. The legend "Chang'e flies to the moon" (嫦娥奔月) lies behind the Mid-Autumn Festival (featuring mooncakes, as it were). Point is, the names of Chinese space missions are every bit as carefully steeped in tradition as, say, Mercury/Gemini/Apollo.

The legend "Chang'e flies to the moon" (嫦娥奔月) lies behind the Mid-Autumn Festival (featuring mooncakes, as it were). Point is, the names of Chinese space missions are every bit as carefully steeped in tradition as, say, Mercury/Gemini/Apollo. The People's Republic of China doesn't think of itself as a "Nation State." Instead, it thinks of itself as a "civilization state." A part of PRC's self appointed charge is to p…

That's very interesting to hear. I wonder if it is something specific to that corporation, or perhaps your role at the corporation, though? All the Chinese-born people I know would be pretty surprised if any non-Chinese person could read Chinese.

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

#182

Post by stallmanite »

ohitsdom wrote: post #94
skilled wrote: post #76

Earlier quoted context omitted.

Awesome, great to know. Didn't know about the DSN so going to read upon that.

For others that might not have seen it, there's a cool live dashboard of the DSN so you can see which spacecraft are currently transmitting: https://eyes.nasa.gov/dsn/dsn.html

Thanks for this link, never heard of this and it’s been fun for my son and I.

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

#183

Post by mturmon »

jackconnor wrote: post #174
mturmon wrote: post #173

Earlier quoted context omitted.

The use of a relay is something less than "stunning" and "brilliant". The use of relay satellites when ground stations do not have line-of-sight to the primary spacecraft (or, when you have reduced bandwidth or other restrictive conditions) is standard practice. This concept is used to relay telemetry from Mars landers, for instance.

You realize the words "stunning" and "brilliant" are subjective, right? Your "standard practice" here is both incredible AND the first time ever done in this scenario to achieve something brand new in space travel. Not sure why you need to tell people not to like things, but it's a really bad habit you should break.

I do like the notion of using a relay.

In 1999, JPL lost Mars Polar Lander, and didn't have telemetry to know why. One of the major lessons learned from this loss was to always have telemetry of Entry, Descent, and Landing (EDL). This telemetry is usually provided by a relay. So despite the fact that we both like it, using relays is not new.

(See sec. 5.1 of [1]: "The omission of EDL telemetry was justifiable from a project perspective. However, the loss of MPL without yielding any clues as to the cause of the loss jeopardized the potential for success of future Mars landers. Therefore, the decision was not justifiable in the context of MPL as one element of the ongoing Mars exploration program.")

I like that they put it in an orbit about the Earth-Moon L2 point. I think it's the first such satellite there.

[1] https://spaceflight.nasa.gov/spacenews/releases/2000/mpl/mpl...

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

#184

Post by pugworthy »

joejerryronnie wrote: post #21
XorNot wrote: post #19

Earlier quoted context omitted.

I'm pretty happy if China wants to throw shade at the US over space program accomplishments. I'd prefer a measuring contest over space accomplishments then building more earth-bound weapons systems.

And how long before the space program accomplishments start looking just a little like space-based weapons systems. I’m sure Chinese military leadership can extrapolate as well as the Pentagon can.

Military interest in the moon goes back quite a ways. See https://en.wikipedia.org/wiki/Lunex_Project for example, and https://en.wikipedia.org/wiki/Project_Horizon

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

#185

Post by peter303 »

sizzzzlerz wrote: post #111

Does China have an equivalent to NASA's Deep Space Network tracking stations? By deploying large antennae in the US, Spain, and Australia, the US was able to maintain 24/7 contact with the space missions. Granted, this isn't a manned mission but I'd still think that they'd want to have continuous comms to their lander.

There was a television story about Chinas DSN station in Argentina. I think it was 60 Minutes, but could not find the link. The story alleged China could be spyingof world satellites with these radio dishes. The locals are of mixed opinion. They like the economic infusion from China but fearful they could get more pushy. The Chinese workers mostly keep to themselves, but there is a grocery store and new restaurants for them.

My guess is that they would need a third location for unbroken 360 degree coverage. I would gues somewhere in Africa would do it. They have lots of development projects ther.

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

#186

Post by peter303 »

Israel and India may be sending landers to the Moon too. India has sent orbiters to the Moon and Mars. https://en.m.wikipedia.org/wiki/Mars_Orbiter_Mission_2 https://en.m.wikipedia.org/wiki/Chandrayaan-2

An Israeli group got pretty far with an entry in the lunar lander XPrize. But the prize reached its deadline dates and expired. I hear they may be shopping for a deep space launch vehicle.

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

#187

Post by Retra »

Rebelgecko wrote: post #160
Retra wrote: post #118

Earlier quoted context omitted.

Do you know why NASA doesn't partner up with China? Because it sounds like you think those political differences are insignificant.

It's currently illegal for NASA to work with China. There's been a line in the NASA appropriations bills for the last 5 years or so saying none of the money they're receiving can be used bilaterally or in cooperation with China

That describes the mechanism, not the rational.

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

#188

Post by philwelch »

pastor_elm wrote: post #134
xupybd wrote: post #87

Earlier quoted context omitted.

They have to be careful then. Apollo now means more about the moon landings than the old traditions to me. I don’t know if that’s something the Chinese would like to have happen to their traditions.

better than what Nike is now

The swoosh logo of the Nike company supposedly resembles the wings of the goddess Nike as seen in some ancient sculptures.

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

#189

Post by philwelch »

headsupftw wrote: post #166
Retra wrote: post #118

Earlier quoted context omitted.

Do you know why NASA doesn't partner up with China? Because it sounds like you think those political differences are insignificant.

Speaking of significant political differences, NASA has been partnering with Russia and nobody seems to have a problem with that.

It's not necessarily the case that nobody has a problem with it, it's just the status quo, and the front lines of most political issues are on one side of the status quo or the other. The "don't work with China" side would push across to "stop working with Russia" if they had the strength to.

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

#190

Post by stcredzero »

swampthing wrote: post #181
stcredzero wrote: post #161

Earlier quoted context omitted.

The legend "Chang'e flies to the moon" (嫦娥奔月) lies behind the Mid-Autumn Festival (featuring mooncakes, as it were). Point is, the names of Chinese space missions are every bit as carefully steeped in tradition as, say, Mercury/Gemini/Apollo. The People's Republic of China doesn't think of itself as a "Nation State." Instead, it thinks of itself as a "civilization state." A part of PRC's self appointed charge is to p…

That's very interesting to hear. I wonder if it is something specific to that corporation, or perhaps your role at the corporation, though? All the Chinese-born people I know would be pretty surprised if any non-Chinese person could read Chinese.

All the Chinese-born people I know would be pretty surprised if any non-Chinese person could read Chinese.

My experience is that attitudes are often quite different if you look like a Chinese person.

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