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NASA Will Land InSight on Mars With Cunning -- and Lots of Cork (wired.com)
On Monday, November 26th, NASA will attempt to land the InSight spacecraft on Elysium Planitia, a vast plain just north of the Martian equator. If NASA is successful, InSight (short for Interior Exploration using Seismic Investigations, Geodesy, and Heat Transport) will be the first mission to investigate Mars' deep interior with thermal probes and seismometry, an approach scientists think will address questions about the red planet's formation and composition. But first, the spacecraft must land. From a report: Getting to Mars is hard, but NASA engineers consider entry, descent, and landing -- the seven-minute period in which mission planners are helpless to intervene, due to the tremendous distance between Mars and Earth -- the riskiest sequence in the entire mission. Here's how NASA plans to pull it off.
For InSight, the action will begin Monday, November 26th at around 11:47 am PT (2:47 pm ET). That's when the lander is slated to hit the top of Mars' atmosphere, at an altitude roughly 43 miles above the planet's surface. On contact, the spacecraft will be blazing along at a not-so-cool 5500 meters per second. That's 12,300 miles per hour. At those speeds, the primary concern for NASA's engineers is friction. Mars' atmosphere, which is roughly 100 times thinner than Earth's, plays a vitally important role in InSight's arrival: Bleeding the spacecraft of its kinetic energy. Yet the atmosphere poses a significant threat, as well. The resistance it exerts on InSight's heat shield, a 419-pound enclosure composed primarily of crushed cork, will drive the temperature of the protective barrier to temperatures greater than 2,700 degrees Fahrenheit -- hot enough to melt steel.
For InSight, the action will begin Monday, November 26th at around 11:47 am PT (2:47 pm ET). That's when the lander is slated to hit the top of Mars' atmosphere, at an altitude roughly 43 miles above the planet's surface. On contact, the spacecraft will be blazing along at a not-so-cool 5500 meters per second. That's 12,300 miles per hour. At those speeds, the primary concern for NASA's engineers is friction. Mars' atmosphere, which is roughly 100 times thinner than Earth's, plays a vitally important role in InSight's arrival: Bleeding the spacecraft of its kinetic energy. Yet the atmosphere poses a significant threat, as well. The resistance it exerts on InSight's heat shield, a 419-pound enclosure composed primarily of crushed cork, will drive the temperature of the protective barrier to temperatures greater than 2,700 degrees Fahrenheit -- hot enough to melt steel.
Thus far, NASA is the only organization to have much luck with Mars EDL.
There were a series of Soviet probes in the 1960's and 70's, but the only one to live on the surface was Mars 3, and then only for 20 seconds before it stopped. They also had two probes in the late 1980's, Phobos 1 and 2, but both quit before successfully landing on Phobos. Also their Phobos-Grunt mission in 2011 failed. They did have some luck with flyby missions however.
Likewise Europe's Beagle 2 lander was never heard from again after it touched down on Mars. However the orbiter portion of the mission worked. Europe's 2016 Schiaparelli lander attempt also failed before touchdown and was never heard from again.
NASA had the first full lander success (beyond a few seconds of operation) with Viking 1 and 2 in 1975. Since then they've had a few failures such as the Mars Climate Observer and Mars Polar Lander, but many successes too, even including rovers. NASA seems to be the only space exploration organization adept at landing probes on Mars and making them work. That's no guarantee however, and there are many, many things that can go wrong, some of them unpredictable.
Mars EDL is hard.
Wow, didn't we already landed there like 20 years ago first time?
Viking, 1976: 42 years ago.
Should be easy with current tech?
Easier, perhaps. But not easy.
NASA's been successful with Mars landings since the loss of Polar lander, and that was 20 years ago. But Mars landings are not easy. For the entire planet Earth, the success rate for missions to orbit or land on Mars is 50% successful, 50% not; with the most recent failure the ESA Schiaparelli EDM lander. So, don't take Mars landings for granted.
Or it was all massive BS and a lot of Photoshop?
You know, that isn't really funny, because millions of people actually believe that shit. There really doesn't seem to be any possible satire conspiracy theory so extreme that people don't believe it.
http://www.geoffreylandis.com
Lockheed Martin has produced an animation of the entry descent and landing. Go ahead and watch it, once, then forget about it. It unfortunately is not nearly as informative as, say, the 7 Minutes of Terror video from Curiosity, or the whimsical bounce landing from Spirit and Opportunity.
Reentry heating is primarily caused by rapid compression of the air caused by the speeding vehicle. A bottle of aerosol gets cold when its contents are released and decompressed. Well, the reverse process of compression causes heat to be emitted. And that's what causes most of the heating during reentry, not friction.
https://en.wikipedia.org/wiki/Atmospheric_entry
And give it all to SpaceX.
Which is funded by NASA.
Slashdot commenters seem to forget that the entire reason SpaceX didn't go bankrupt after the third failure of the Falcon-1 is that NASA believed in them and stepped in to fund them to design and build the Falcon-9, at a time when nobody else in the world saw anything in them other than a fringe company that tried to make a rocket and failed.
If you're asking what NASA has accomplished since the 60s: well, this is one thing.
Without NASA there would be no SpaceX.
p>You know, that isn't really funny, because millions of people actually believe that shit. There really doesn't seem to be any possible satire conspiracy theory so extreme that people don't believe it.
Stanley Kubrick filmed the fake moon landings, but he was such a perfectionist he made NASA go to the moon to do it.
The shepherds did so well protecting the flock that the sheep no longer believed that wolves existed.
We made heat shields that did a much harder job in the 60's, bringing Astronauts home; this is something harder?
If you understand the process of EDL on Mars then yes. It's much harder to land spacecraft on Mars than on Earth. It would be better if Mars did not have an atmosphere. The problem is that Mars has just enough atmosphere to where you have to deal with it during EDL. This means you need a good heat shield that problem is basically solved like you said. Because the atmosphere on Mars is so thin it's difficult to slow down the spacecraft unlike on Earth. This requires some atmospheric gymnastic for the spacecraft to perform during EDL in order to slow the aircraft down in the atmosphere of Mars down to ~1000Mph in which case a supersonic parachute is deployed. As you can imagine deploying a parachute that has to be extremely light yet handle 8000+ pounds of load at 1000Mph is no small task. However given that Mars atmosphere is so thin the parachute alone will only slow the load down to 200 Mph. What do you do then?? Well retro rockets have to kick in and slow the craft down to landing speed but it's not that simple, you have can't land the load with retro rockets because the massive amount of dust will be all over the newly delivered load. So you need to use retro rockets in a sky-crane configuration attached to the sky-crane that will lower the load down to the surface from the sky-crane then detach the sky-crane and fly it away so the landing site is not disturbed. And you have to do this with a very delicate science laboratory on wheels and get it there on one piece with out any shock damage what-so-ever.
See here for more information
It appears they're not using a sky crane for this landing.
https://www.youtube.com/watch?v=C0lwFLPiZEE
Of course the public are interested, especially with 4K televisions, just think of looking at beautiful, awe inspiring 4k footage of the Moon every day, as the astronauts explore more and more of it.
Meh, if you've seen one dusty gray crater you've seen 'em all.
"When information is power, privacy is freedom" - Jah-Wren Ryel
Probably by using the same bioburden reduction technique that most of the instruments on this mission go through: dry heat microbial reduction.