I know no one visits my blog for the latest news and opinion on space exploration, but a probe named Messenger just blew past Mercury and took some great photos I think are very exciting. My interests, my blog, my rules.
.
Nobody's visited Mercury since the single Mariner 10 mission more than 30 years ago, and that machine photographed less than half the planet. Messenger will eventually go into orbit around Mercury and shoot the entire thing in high resolution. This pass is just a rendevous to begin to slow it down. Launched in August 2004, Messenger already flew by Venus once, Earth once, and Venus again, using those planets' gravity to change speed and direction, and it'll fly past Mercury again in October 2008 and September 2009 before parking itself in orbit in March 2011.
.
No doubt some interesting science will come out of Messenger, but to me the excitement of a mission like this is more visceral: we are seeing things that literally no one has ever seen before. How often can you say that? Until today, we didn't know what more than half of an entire planet in our solar system looked like. The beauty of modern technology and communication is that everyone on the planet can find out nearly as quickly as scientists download pictures from the probe. And a few minutes later, I can post them on my blog for you.
.
That amazes me.
.
2 comments:
Your last point is one I've been marveling about for the past several days, usually in the context of boring young'uns about how long it took for us to see those Mariner 10 images in '74 and '75 from its three working flybys -- all of which were over the same hemisphere of the planet.
Messenger's convoluted and long course to the third-closest planetary orbit also brings up an opportunity to point out a surprising bit of celestial mechanical trivia: Mercury is the hardest planet to get to in launch-energy terms. Earth orbits the Sun at about 67,000 miles per hour. Essentially all of that has to be canceled out to "drop" a probe down to Mercury, but less than half of that* has to be added to propel one out of the solar system altogether.
*1/sqrt2
I heard about this in Geology class; sounds pretty cool! And the "Messenger" was very well named too, since it will end up in Mercury's orbit.
Post a Comment