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Comment by yummybear | Hacker News Reader

What a shame. The only consolation, if any, is that they are not the first ones to crash on Mars. If I remember correctly the historic chances of landing successfully on Mars is about 50/50.

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Reminds of the "Seven Minutes of Terror" video that NASA put out ahead of the Curiosity landing explaining how they intended to make it safely to the surface.

https://www.youtube.com/watch?v=Ki_Af_o9Q9s

(Note: I get goosebumps every time I watch this, absolutely amazing problem solving.)

I'm still amazed that it succeeded. I was prepared to bet quite a bit of money that at least one of the many quite complicated stages of the landing would fail. I'm happy I was wrong.

To me, the air bags[1] used to land the Spirit and Opportunity rovers seemed like a saner way to go than trying to deposit them gently directly on to the surface using a sky crane. The reported reason the sky crane was used for Curiosity is that it was too heavy for the air bag approach.

[1] - https://www.youtube.com/watch?v=XRCIzZHpFtY

It's 185 kg vs 899 kg. I am already a bit surprised that it worked to land Spirit and Opportunity, but the lower gravity probably helps.

But the Spirit and Opportunity EDL also involved retrorockets in addition to a heatshield, a drogue chute, a parachute and the airbags - it's just that the retrorocket part didn't have to be as precise as with Curiosity.

I actually laughed the first time I saw it because it looked so much like a Goldberg machine... But it cost 500M$... And they only got one try.

Just about! For lots of fun info, check out the interplanetary Expensive Hardware Lob League:

https://www.strudel.org.uk/lob/

Ha! This deserves some credit. The tone of the writing makes me think of Starship Troopers. Very tongue in cheek and very funny.

This deserves its own thread entirely! Awesome.

It was a trial run lander, the real one comes later. The primary purpose of the mission was the orbiter which is functioning, and lander testing, which failed but hopefully they get useful data from the failure.

The chances of landing are 100%.

But not successfully...

I believe rocket scientists make a distinction between landing and impacting.

Different intensities of lithobraking.

rapid unschedualed disassembly event.

Some landers failed to reach Mars and crash land. Check the list at https://en.wikipedia.org/wiki/List_of_missions_to_Mars

He means that whether it crashes or not, it's a landing.

However there are projects that completely miss their target and just float in space, so even then it's not 100%.

That was my point, better worded :-)

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