Sure Hubble's pictures are prettier, but there's a lot of cool science coming out of the nifty MESSENGER spacecraft. She's up for a third Mercury fly-by in two weeks. She'll go into orbit in 2011 and she's the first spacecraft there for 30 years!
Already we've seen her video leaving Earth on a 2005 fly-by. Her first two Mercury fly-bys showed part of the planet we had never seen, and also answered some questions about the Caloris basin (and its formation), the planet's exosphere, and the planet's magnetic field.
Go visit the website to hear more or read from the special issue of Science from May 1, 2009.
Here's a picture from her last fly-by:
I am very excited to see what more we can learn from this mission.
The mission web site has some good stuff on it, although I think the "gallery" could be done better.
The "Special Issue of Science" (like all other issues) is hidden behind a pay-wall (sigh). On the one hand, I understand the need for Science to charge (but $15 for one article for *24 hour access* - WTF!). On the other hand, taxpayers paid for the mission, the data, and the salaries of many (most?, all?) of the people involved, so why do we have to pay again? This is an old debate; I wonder how it will eventually be resolved, because the current situation is not sustainable.