Odysseus has less than a day left on the Moon before it freezes to death | Hacker News Reader

Odysseus has less than a day left on the Moon before it freezes to death

arstechnica.com

44 pointsnickthegreek29 comments

Odysseus is acting out the fictional short story "A Walk in the Sun" [0] where a girl crash lands on the moon and has to keep walking west to stay in the sunlight so she doesn't freeze to death.

[0] https://en.wikipedia.org/wiki/A_Walk_in_the_Sun_(short_story...

Futurama writers must have read that:

https://en.wikipedia.org/wiki/The_Series_Has_Landed?wprov=sf...

> has to keep walking west to stay in the sunlight so she doesn't freeze to death.

Reminds me of the opposite problem we can see in "The Chronicles of Riddick" (2004). Keep running to stay in the night side of the planet to survive the sunrise.

With great music "The Chronicles of Riddick | Outrunning the Sun" https://www.youtube.com/watch?v=sGihB0gxgko

One of the earliest Star Wars novels (now part of the noncanonical “extended universe”) featured a walking mining colony that walked across a planet to stay in its night side.

The story: https://www.baen.com/Chapters/0671878522/0671878522___1.htm

A slightly smarter protagonist would have headed slantwise for the nearest pole. 200 miles/day is a pretty hard slog, but close enough to a pole, you might get along on just one. Being at the crash site so rescuers can find you, besides, would be hard to calibrate.

So both recent landers tipped over?

Yes.

Yeah, that confused me for a bit too; real-life deja vu.

Maybe a Knex-style mesh ball design would be a good way to construct landers where it could land, roll to a somewhat upright position, flatten out or eliminate the ball mesh, and then deploy upright with solar ready to go. Having 2 entire missions that got us to the surface without a hitch and losing the lander just due to positioning is so unfortunate.

Like this, but rockets instead of rotors:

https://www.wired.com/2015/02/drone-bounces-around-disaster-...

I googled quite a bit to find a picture of what I meant and this is exactly spot on

> Maybe a Knex-style mesh ball design would be a good way to construct landers where it could land, roll to a somewhat upright position, flatten out or eliminate the ball mesh, and then deploy upright with solar ready to go.

Kind of like the Mars Pathfinder-style landing system? They were tetrahedrons that could land on any face, then right themselves while unfolding.

It turns out that there is very little wiggle room for lateral motion on the moon. The landers have just as much inertia as they do on earth, but the low gravity means the legs don't help with stability as much as you'd expect. And I couldn't help but notice that Odysseus has a rather tall profile.

But why? Why not build it like a blanket? Force things to fall the right way with physics?

This is mostly because rockets are cylinders. It's easy to get a long thin tube into space than an odd shape.

> So both recent landers tipped over?

Bad design choice. There are better ways to do it.

If only they had thought to ask you!

When you try to land on the Mun in KSP you quickly realize it’s hard as hell to not tip over. It requires a lot of finesse and skillful cherry picking of a landing site. The micro gravity relative to horizontal velocities the grade of crater pits, etc makes it hard. And that’s a video game simulation with human being tweaking the landing.

What baffles me is how they launched without navigation turned on. That like something that shouldn’t be possible by construction.

Whilst I realise that it would eat into the weight budget of such landers, I reckon adding a fuel cell with enough fuel to last through the lunar night, which keeps the lander and its batteries alive, should be a standard and integral part of such craft.

Of course, that would mean taking less science with it, and increase the cost of the lander, and quite possibly if I can think of such a thing, engineers more clever than I am have already considered such.

Still, congrats to the team for managing to at least soft land on the moon. No doubt they'll be learning a lot of lessons from this mission.

Fuel cells aren't some magic solution, they need fuel and it wouldn't be recovered. The normal operating procedure for lunar craft is to expect them to die on their first night. There's not a lot of advantage to sitting around in the same spot, equipping a probe to survive the night isn't worth it.

It's just this one landed badly and "night" for it's panels is going to come sooner than expected.

I’m surprised the battery doesn’t just recharge after one or more cycles.

It’s too cold for too long, the electronics get damaged. Note that the lunar night lasts about 14 earth days.

Sounds like a problem a small pellet of nuclear fuel could resolve even without a reactor.

Sure. That comes with some paperwork, but Mars rovers have nuclear fuel for example.

This may be harder for a commercial lander like this one though.

What was the mission for Odysseus, anyway? Was it just supposed to land there, pretty much?

Landing there is part of it, yes, as part of the Commercial Lunar Payload Services program.

It brought along a bunch of NASA and commercial payloads as well.

https://www.space.com/intuitive-machines-odysseus-moon-lande...

Did we get any footage from this mission?

I’m sorry, but the thing even looks top heavy.

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