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Getting the Latest Rover To Mars
derGoldstein writes "New Scientist has a great video up detailing every step of how the latest Mars rover will reach its target and get deployed. It's drastically different than the bouncing air-bag delivery system previously used (YouTube video)."
This rover is FAR larger the current ones, those tires? Not cute cart wheels, they are roughly the same size as a car tire. The entire vehicle is easily the size of a large SUV although far more open. (Hey nasa, if you want to make things understandable how about instead of adding sounds in space, maybe project a human next to thing so we get a sense of scale)
A bouncing ball for this vehicle wouldn't need to be far to large. It is the old story of how spider won't even notice a 4 meter fall, a human would shatter bones and an elephant would go splat.
There are a lot of risks with this method, so many parts that can fail, but if you want something big to land safely...
Not that this is new. There are airdrop uses on this planet that involve just wrapping what you want to drop in something bouncy and throwing it out of an aircraft, works for small supplies in remote areas where a parachute might drift to far and the russians have used rocket decelerated chute systems for dropping tanks out of aircraft. Because finding enough bubble wrap for a tank is a hard.
Did I complain yet about the sound in space? Yes? Well, it is a pretty big fucking issue. Everything you need to know about the US can be summarized as a NASA science video having sound in space... why not go the whole way and include cute green aliens on mars to show the life you might have found if Mars wasn't the hell hole it is?
MMO Quests are like orgasms:
You may solo them, I prefer them in a group.
The rover is too big/heavy for the bounce trick they used for the previous ones.
Heat shield/parachute entry is not complicated. Apollo era technology.
The retro rockets are like what the moon landers used. Also Apollo era technology.
The only new thing here is the tether. I suspect it uses explosive bolts to release and that is Apollo era tech.
While it looks complicated, I think we should have mastered those things pretty well by now.
When I saw the last stage I almost fell out of my chair!. What the hell happened to keeping it simple!
It's no worse than the various lunar landers. The real question is whether they can get the budget to send that much mass to Mars.
Landing anything big on Mars turns out to be quite hard. There's not enough atmosphere for a soft parachute landing. But there's enough atmosphere to require a heat shield while plowing through it. Then there's not enough atmosphere to brake from Mach 5 to Mach 1 before running out of altitude. There's too much gravity for a full rocket-powered descent. A rocket facing into the atmosphere won't work until the craft has slowed below supersonic speeds.
That's what leads to what looks like an overly complex system.
http://en.wikipedia.org/wiki/Mars_Science_Laboratory#Power_source
The Curiosity rover will be powered by radioisotope thermoelectric generators (RTGs), as used by the successful Mars landers Viking 1 and Viking 2 in 1976.[29][30] Radioisotope power systems are generators that produce electricity from the natural decay of plutonium-238, which is a non-fissile isotope of plutonium used in power systems for NASA spacecraft. Heat given off by the natural decay of this isotope is converted into electricity, providing constant power during all seasons and through the day and night, and waste heat can be used via pipes to warm systems, freeing electrical power for the operation of the vehicle and instruments.[29][30]
The Curiosity power source will use the latest RTG generation built by Boeing, called the "Multi-Mission Radioisotope Thermoelectric Generator" or MMRTG.[31] Based on classical RTG technology, it represents a more flexible and compact development step,[31] and is designed to produce 125 watts of electrical power at the start of the mission and 100 watts after its minimum lifetime of 14 years.[32][33] The MSL will generate 2.5 kilowatt hours per day compared to the Mars Exploration Rovers which can generate about 0.6 kilowatt hours per day.[13]
I am in absolute awe after watching the video about the new rover. As people bicker over whether NASA's miniscule budget is worth it, because "space isn't important", it's nice that NASA can still bring out that child-like wonder in me. How can you not be amazed that we can send a robot like this to another planet, land it safely with precision, and study the composition of the planet from millions of miles away? Isn't that awe worth a few billion dollars a year, even if "it doesn't benefit me"?
(Also, it has a laser tricorder. I mean, come on.)
"Running out of altitude" is the most awesome synonym for hitting the ground I've yet heard.
Lithobraking
http://michaelsmith.id.au
The only permanent, extra-terrestrial life-supporting, man-made object is the ISS. That needed 14 years of construction (predicted to last only about 14 more once it's finished), needed the Americans, Soviets, Europeans and Japanese to all abandon their individual projects and concentrate on only that, costs about 100bn Euros, and is 200 miles away.
The Moon is 200,000 miles away. Mars is 150,000,000 miles away.
There will be no short-term supply trips to give people several years worth of food (i.e. the time until we can send a "real" supply) - hell, food would constitute the vast majority of their payload because you won't be growing anything self-sustainable on the Moon/Mars for at least a year even under ideal "Earth-like" conditions simulated inside some kind of greenhouse (it's called farming - plant stuff, wait a year, eat it).
There's a hell of a lot less heat and you're going to be constantly pumping heat into a cold void in order to keep things at room temperature (considering we can just about rustle-up a handful of watts for the Mars rovers, or a couple of hundred for the new ones using radioactive materials, your heating bill is going to be... well... astronomical). We just about managed it for a handful of days in the past, for just spacesuits. The Apollo astronauts barely stayed a day.
There will be a bit more than the ISS's 10 major incidents in that time (not counting the VASTLY increased chances of problems with the travel outside the Earth's influence, landing and living on another rock that we can barely keep a rover running on) and no backup to send spare parts within weeks like we've done with the ISS.
Just think about the first few days - if you don't manage to ship enough stuff and people to build a air-tight shelter against the dust storms, warm enough to keep a human happy, pumped full of oxygen, large enough to hold decent amount of food, people and living space, in one of the most hostile environments that humans would ever have set foot upon, you're dead before you even start. That's assuming those humans even make it there - most of the stuff we've sent to orbit Mars hasn't made it at all or lasted anywhere near it's planned lifetime - the exceptions don't bring up the averages much.
Humans are literally two-three days away from death at any time. Rovers can live for decades and we can send 100 of them for the cost of one man (just in a single mission, if we so wanted). It was estimated recently that Apollo cost $170bn (adjusted for today) for a handful of people to walk on the moon for a day. The Mars rovers cost US$820 million originally, nearly $1bn with all the extensions. Curiosity costs about $3bn. That entire program cost less than 1-2% of the cost of putting a couple of men on the Moon for only a day.
Humans aren't built for travel. Wherever we go we have to take Earth with us. And that, quite literally, costs the Earth each time.
And that's exactly why NASA is testing the bejesus out of it. Including delaying for exactly that reason
Bouncy rover is good and simple, but the Sojourney rover is the size of a toy car, Curiosity is about the size of a Mini Cooper.
http://science.howstuffworks.com/mars-rover3.htm
They got burned with rockets (no pun intended) on Mars Polar Lander, but guess what, Viking landed with rockets. And Mars Phoenix, and several other craft.
I'm skeptic about the whole crane thing, but they want that for a 'precision landing'.
how long until