Recent Moon landings

[Shadowy Man]

Should search, but I wonder what reason there is for designing the lander to be top heavy and prone to toppling?

I believe it had to do with the way the fuel consumption would affect the center of mass, but I’m sure there’s a longer answer out there.

Had they come straight down instead of laterally it would have been less likely to topple, so they’ll need to understand what led to the trajectory they had.

But it certainly does seem to suggest potential redesigns.

Straight down will cost you extra fuel, you do not want to kill your horizontal velocity any earlier than you have to.

By “straight down” I was referring to the final moments. They hit the ground moving at an unplanned 2mph horizontal speed. The plan was for 0mph horizontal speed at the time of touchdown.

Which doesn't change the basic issue. Killing your horizontal velocity before you have to costs you fuel. The optimum course has your rocket only reaching no horizontal speed/entirely vertical orientation at touchdown. There is also the issue that control authority always costs, you don't put more of it than you need. (Note: KSP is a horrible model in this regard, control authority is way, way overdone for the sake of gameplay.)

I don’t think we are disagreeing here. They were supposed to touchdown with zero lateral velocity yet they had 2mph. That was likely a major factor in the topple.

It seems clear now that the craft thought it was higher up, which is likely why it still had horizontal velocity. As you point out you want to wait until the very end to null that out.

 

[lpetrich]

Farewell Forever, Odie: Odysseus Lunar Lander Has 'Permanently Faded' - CNET - March 26, 2024 10:40 a.m. PT
noting
Intuitive Machines on X: "As of March 23rd at 1030 A.M. Central Standard Time, ..." / X - 11:45 AM · Mar 23, 2024

As of March 23rd at 1030 A.M. Central Standard Time, flight controllers decided their projections were correct, and Odie’s power system would not complete another call home. This confirms that Odie has permanently faded after cementing its legacy into history as the first commercial lunar lander to land on the Moon. 3/3

So it did not survive the cold lunar night.

Weather on the Moon

The lunar exosphere is too skimpy to trap or spread the Sun’s energy, so differences between sunlit and shadowed areas on the Moon are extreme. Temperatures near the Moon’s equator can spike to 250°F (121°C) in daylight, then plummet after nightfall to -208°F (-133°C). In deep craters near the Moon’s poles, permanent shadows keep the surface even colder — NASA’s Lunar Reconnaissance Orbiter has measured temperatures lower than -410°F (-246°C). These forever-dark places harbor ice deposits that may be billions of years old.

 

[lpetrich]

 List of missions to the Moon

The next one is Chang'e 6 - China - 2024 May - South Pole / Aitken Basin - lander, sample return

followed by two more late this year, and several in the upcoming years.

 

[Elixir]

 List of missions to the Moon

The next one is Chang'e 6 - China - 2024 May - South Pole / Aitken Basin - lander, sample return

followed by two more late this year, and several in the upcoming years.

They're going to steal all the water.

 

[bilby]

 List of missions to the Moon

The next one is Chang'e 6 - China - 2024 May - South Pole / Aitken Basin - lander, sample return

followed by two more late this year, and several in the upcoming years.

They're going to steal all the water.

Mr President, we cannot allow a lunar water harvesting gap!

 

[Loren Pechtel]

 List of missions to the Moon

The next one is Chang'e 6 - China - 2024 May - South Pole / Aitken Basin - lander, sample return

followed by two more late this year, and several in the upcoming years.

They're going to steal all the water.

Mr President, we cannot allow a lunar water harvesting gap!

View attachment 45866

Well, I actually found the Rifle Gap.

Spoiler

It's outside the town of Rifle, Colorado.