Skip to comments.NASA spacecraft now circling Mercury — a first (orbit is right on the money)
Posted on 03/17/2011 8:44:44 PM PDT by NormsRevenge
WASHINGTON For the first time, Earth has a regular orbiting eye-in-the-sky spying on the solar system's smallest and strangest planet, Mercury.
NASA's spacecraft called Messenger successfully veered into a pinpoint orbit Thursday night after a 6 1/2-year trip and 4.9 billion miles and tricky maneuvering to fend off the gravitational pull of the sun. It is the fifth planet in our solar system that NASA has orbited, in addition to the Earth and the moon.
(Excerpt) Read more at news.yahoo.com ...
March 17, 2011
MESSENGER Begins Historic Orbit around Mercury
At 9:10 p.m. EDT, engineers in the MESSENGER Mission Operations Center at the Johns Hopkins University Applied Physics Laboratory (APL) in Laurel, Md., received the anticipated radiometric signals confirming nominal burn shutdown and successful insertion of the MESSENGER probe into orbit around the planet Mercury.
First Orbital Image Planned for March 29
Release Date: March 14, 2011
This first planned image is scheduled to be taken on March 29, 2011, 7:40 UTC, or 3:40 am EDT. Over the subsequent six hours, MESSENGER will acquire 364 images in total before beginning to downlink the data to Earth.
John Batchelor just talked about this on his show. How exciting.
Cant wait for the pics of the poles
This must be doing wonders for Islamic self-esteem.
Better to have them circling Mercury than Uranus, I always aay.
Bet they won’t have any trouble with poor lighting on the sunny side.
Uh... this may be a dumb question, but if it’s ninety-three million miles to the sun, why is it four and a half billion miles to Mercury...?
Good question. Another ARTICLE says Messenger traveled 96 million miles. Much more plausible, eh. Amongst other things it made three passes around Mercury before being inserted into orbit.
Orbital mechanics. Our spacecraft don’t have the engines to ignore Newtonian laws yet, so we have to do everything using gravity assist from various other planets. Plus, getting something close to the sun without having it fall in is really tricky. We had to fly the craft by Earth once, Venus twice, and Mercury twice (including the final orbital insertion). That doesn’t include a couple of solar orbits as the craft traversed the intervening space between each of the other planets. You can see the whole trajectory at http://upload.wikimedia.org/wikipedia/commons/5/5e/MESSENGER_trajectory.svg
And that article would be wrong. The spacecraft is now about 93-96 million miles away from earth, but the actual distance traveled is the 4 billion miles. It took more than 6 years to get to Mercury, as it had to do a whole bunch of orbits around the sun along the way. My previous post has a link to the trajectory diagram.
So did the probe go back in time, like the Enterprise when it used the Sun’s gravitational field?
The first time, we get halfway across
when we run out of gasoline.
We got to go back.
Then I take twice as much gasoline.
This time, we were just about to land,
when, what do you think,
we run out of gasoline again.
Back we go and get more gas.
This time, I take plenty gas.
We get halfway over,
when what do you think happened?
We forgot the airplane.
Bet they won't have poor lighting on the other side either. Plenty of mercury in a CFL light, so there must be plenty of CFL light on mercury.
Gotta love a guy that knows his Marx brothers!
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