How to bring a 3.3 tonne laboratory from 21,240km/h to zero in 7 minutes...

[antipody]

Was reading Science in the bath tonight and there was a good article about Curiosity's landing next week. Linked to the NASA JPL animation. Pretty cool preview...

http://scim.ag/rovervideo

Not only will NASA have to slow the most massive load ever delivered to another planet's surface from hypervelocity bullet speeds to a dead stop, all in the usual "7 minutes of terror". But NASA is also attempting to deliver Curiosity to the surface of Mars more precisely than any mission before, within a 20-kilometer-long elipse, some 240 million kilometers from Earth.

Six times before, NASA has managed to land spacecraft safely on Mars, starting with the two Viking landers in 1976. This time, NASA planners wanted a bigger and better -and therefore heavier- rover to advance the search for life. Curiosity, clamped inside its entry vehicle like the innards of a clam, weighs in at 3.3 tons-three times larger than any previous entry vehicle. Still, as in past missions the job of safely braking the rover from 21,240km/h falls to the drag of the wispy martian atmosphere. Starting at Mach 20, the bullet like heat shield bears the brunt of the slowing. Then a lone parachute deploys at Mach 2.

What happens next is bloody awesome...

[Doso]

Absolutely unbelievable, unfortunately most Australians wont give two shits about this but rather what happens next in the Olympics/the shire/being lara bingle etc

sad really

[power]

Science just gives me the biggest buzz, this makes me tingle all over - true progress not a shiny apple device!

[Phido]

I really hope the landing goes well.
We need this rover to make it. Nasa is finally taking Mars seriously.

[RobRoySyd]

After watching the video of how complex this landing is all I can say is even if it goes wrong, serious kudos to them for trying. There must have been a lot of doubters, pushing it through must have been a task in itself.

[Oosh]

Anyone got something that explains the use of this hover-rocket crane-gantry approach as opposed to the simpler retro rocket method like the previous Russian Mars landers and manned US Moon landers?

[sub429]

The video here describes what's involved in the landing. Crazy stuff.

[slobber]

Originally Posted by Doso

Absolutely unbelievable, unfortunately most Australians dont give two shits about the 'lympics
sad really

DL'ing the 310MB vid now from NASA

[kingjam]

Originally Posted by antipody

What happens next is bloody awesome...

Serious nerds

[RobRoySyd]

Originally Posted by Oosh

Anyone got something that explains the use of this hover-rocket crane-gantry approach as opposed to the simpler retro rocket method like the previous Russian Mars landers and manned US Moon landers?

The video does explain why. It's because the rockets will throw up a lot of dust and that could damage the instruments on the rover. I think the Russians landed their unit inside a pod.

[Oosh]

Originally Posted by RobRoySyd

The video does explain why. It's because the rockets will throw up a lot of dust and that could damage the instruments on the rover. I think the Russians landed their unit inside a pod.

So I wonder why not use a pod this time around.
I don't doubt they have good reasons but on the surface it does seem needlessly complicated. At least to me.

[antipody]

Originally Posted by Oosh

So I wonder why not use a pod this time around.
I don't doubt they have good reasons but on the surface it does seem needlessly complicated. At least to me.

Accuracy.

Opportunity used the crane too but finished with an awesome super bounce around the surface for nearly a minute before it stopped. Freaking awesome (even if that video is surreal with the American flag, Arnie and Al Gore).


I wouldn't try that with 3 tonnes. Even if you have a slightly lower g value than on Earth, it's still a massive piece of equipment.

22 June Science explains why Curiousity is special.

"The limited targeting accuracy of the previous generation of rovers [which continue to rock on] kept them out of Gale crater, whose central mound boasts a Grand Canyon-like exposure of Early Mars history.

[Oosh]

Not sure how a pod-based design fundamentally impacts on accuracy.

I appreciate the bouncing bubble wrap version does, but what about a hard aero-shell, opens after landing and rover drives out?

[antipody]

Originally Posted by Oosh

Not sure how a pod-based design fundamentally impacts on accuracy.

I appreciate the bouncing bubble wrap version does, but what about a hard aero-shell, opens after landing and rover drives out?

How do you slow it down? Retrorockets?

What if the thing thinks it's touched down and ready to open when it really hasn't?

NASA reckon that happened to the Mars Polar Lander that didn't survive the 7 seconds of Terror. RIP.

Retrorockets to land on legs worked for the Viking but Curiosity is 3.3 tonnes while the Viking lander was 572 kg.

You've also got to make sure your "aero-shell" doesn't for some reason orient itself upside down or against a cliff obstructing the thing's exit I guess.

From the mag

But landing the much bigger Curiosity on a legged, powered platform would be trickier, Sell says. The bigger lander would be less stable on uncertain slopes, and the whole system would be more sensitive to the critical timing of engine shutdown.

[Diode]

What could possibly go wrong?

Well I'll keep my ears open for teh news, so Monday 6th 3:31pm AEST?