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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.
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.
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
Actually, an ablative heat shield cools itself by the evaporation of the heat shield material.
It took some more searching, but here's an InSight EDL video from JPL