Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Athena spacecraft declared dead after toppling over on moon

theguardian.com

Post reply on HN
Print view View original

291–300 of 360 posts

Re: Athena spacecraft declared dead after toppling over on moon

#291

Post by ForOldHack »

spelunker wrote: post #87
nine_k wrote: post #2

One similarly structured craft (thin and tall) reached the Moon a year ago, and also eventually toppled. Maybe next missions will feature less tower-shaped designs and more crab-shaped designs, at least during the landing phase.

I mean, eventually everything is crab right?

Crabs cook well, but do not fly well,not drop in the vacuum of space well. But by no means dismiss this idea. It is interesting, I just do not know how right now. Their exoskelton legs. If the craft rotated like a cat,and landed like one with a dozen crab legs...where is Adam Savage when you need him?

Re: Athena spacecraft declared dead after toppling over on moon

#293

Post by ForOldHack »

modeless wrote: post #169

I was confused because I saw a picture taken from the private moon lander and it was upright. Turns out two private moon landers recently landed and the first one was successful.

Then have the sucessful one walk over and right the others. It could not be that hard? NASA did not have cellphones. They put rovers on the moon. How about putting a couple of spare battery packs and a remote pilot on a rover? Does Uber and Lyft want to start service early?

Re: Athena spacecraft declared dead after toppling over on moon

#294

Post by somewhereoutth »

celsius1414 wrote: post #81
gtirloni wrote: post #71

Not a native English speaker here, my focus stopped at the subtitle "Robotic private spacecraft touched down about 250 miles from its intended landing site on Thursday". It feels odd to read "robotic private spacecraft" instead of "private robotic spacecraft" but I can't explain why.

You are likely aware of the English language's feature of multiple adjectives (that are modifying the same noun) needing to appear in a certain order to sound "correct". So for example "yellow big balloon" sounds wrong but "big yellow balloon" sounds right. This is because SIZE is supposed to come before COLOR in standard English phrases. In this case, "robotic" and "private" could be similar enough in category to be…

Furthermore, (and not really applicable in this case), you can bring an adjective to the front out of order for emphasis - so yellow big car would mean there were plenty of big cars, but the yellow one in particular. In spoken English there would be heavy vocal emphasis on yellow, and in written yellow would likely be italicized, just to make double sure.

Re: Athena spacecraft declared dead after toppling over on moon

#295

Post by ForOldHack »

inamberclad wrote: post #226

Definitely concerned about the laser rangefinders not working on descent. My recollection is that they were very finnicky instruments. A lot of discussion is happening around the aspect ratio of the Noca-C landers. Part of the reason they're so tall and skinny looking is that the lander is built around two linerless composite fuel tanks. Two big tanks are more efficient than four smaller ones. The legs should definit…

There was also lots of dust. Read digital apollo.

If your tanks are empty, they are now dead weight. Use them as pads.

If you had 30 empty tanks on spikes you could bounce, roll onto the surface.

Again tanks as landing gear.

A delivery craft that crashes somewhere else, or flies over the rights the other two. ( Three for one)

Re: Athena spacecraft declared dead after toppling over on moon

#296

Post by ForOldHack »

ChicagoDave wrote: post #173

I seriously do not understand why moon or mars landing structures aren’t some kind of dodecahedron. It can always correct itself after landing and then “unpack” itself. Someone tell me why we’re not doing this.

There are both a ton of rocks and 1100 foot cliffs.

Drop a Tesla tow truck...( A joke... But you would be able to see the explosion from Earth)

Re: Athena spacecraft declared dead after toppling over on moon

#297

Post by chickenbig »

astar1 wrote: post #280

These 2 failures could have been easily avoidable both times. I really wish there was a push in the US government to create and stockpile plutonium-238 and ensure it's readily available, subsidized, and offered for all US probes/rovers/other scientific instruments in space (whether it be for NASA's use who currently has to ration because of how little they have left, or for private use after approval). Like, why aren…

An alternative to Pu-238 is Am-241 https://www.world-nuclear-news.org/Articles/Can-americium-re... .

The UK has around 140t of trans-uranics in its civilian stockpile, of which an estimated 5.6 tonnes of this is Am-241 per https://www.repository.cam.ac.uk/bitstreams/627b4440-37c9-4e....

Re: Athena spacecraft declared dead after toppling over on moon

#298

Post by hermitcrab »

celsius1414 wrote: post #81
gtirloni wrote: post #71

Not a native English speaker here, my focus stopped at the subtitle "Robotic private spacecraft touched down about 250 miles from its intended landing site on Thursday". It feels odd to read "robotic private spacecraft" instead of "private robotic spacecraft" but I can't explain why.

You are likely aware of the English language's feature of multiple adjectives (that are modifying the same noun) needing to appear in a certain order to sound "correct". So for example "yellow big balloon" sounds wrong but "big yellow balloon" sounds right. This is because SIZE is supposed to come before COLOR in standard English phrases. In this case, "robotic" and "private" could be similar enough in category to be…

>So for example "yellow big balloon" sounds wrong but "big yellow balloon" sounds right.

I'm a native English speaker and wasn't even aware of this adjective ordering rule, until I read about it recently. I had internalised it, but wasn't consciously aware of it. I feel so sorry for anyone trying to learn English as a foreign language!

Re: Athena spacecraft declared dead after toppling over on moon

#300

Post by lou1306 »

somenameforme wrote: post #283
dreamcompiler wrote: post #78

Good advice: 1. Never invade Russia in winter. 2. Make sure your robotic lunar lander has a low center of gravity.

It's not just the center of gravity. I think people really underestimate how hard landing on the Moon is, because counter-intuitively, the lack of an atmosphere makes things harder, not easier. Landing on Mars (or even Venus (!!) - which is the first other planet we ever landed on) is easy mode by comparison. With the lack of atmosphere is that there is no 'natural' attitude/orientation correction. If you're tilted 5…

A bit of Kerbal Space Program really makes you appreciate what an ordeal a satellite landing is. And that is a much simplified setting with e.g., no control lag (even on unmanned crafts), a much closer satellite, etc.

Even just designing a craft that will not topple once landed is punishing.

Post reply on HN