Wednesday, September 13, 2006

Mars: Ready for your closeup?

MRO Mars with EVA Astronaut for Scale
After six months, 426 carefully managed orbital "dips" into Mars' atmosphere, and a few well placed thruster burns, NASA's Mars Reconaissance Orbiter (MRO) reached its near-polar scientific orbit on Monday and will soon (November) be ready to start taking pictures of the Mars surface (and doing a lot of other tasks too). The combination of high resolution sensors and a giant antenna (to enable speedy transmission of all those gigabytes of data back to Earth) means that MRO will return a huge bounty of data on the Martian surface and atmosphere.

I tried to set up MRO's final orbit in Orbiter, but I didn't get the sun-synchronous part right (needs more work but too tired now). The near-polar (planned 92.66 degree inclination) orbit is carefully designed to cross the equator at the same local time on each orbit, providing observations of the surface with nearly constant lighting conditions. The periapsis altitude (low point) of the orbit is about 250 km (and near the south pole), while the apoapsis (high point) is 316 km above the surface (near the north pole). More on the orbit design here (PDF), with general information on the mission here.

P.S. Of course there are no EVA astronauts with MRO at Mars, but I added one for the picture above to show how big this thing is - "bus size" as they say. More pix at Flickr. Note also that the MRO add-on for Orbiter is by Brian Jones, available at avsim.com (file mro.zip).

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