Follow Breakthroughs in Astronomy on Twitter - Part 1

When you signed up for your Twitter account, you probably started following and making some friends, promoted your work or started keeping tabs on the news. If you're an astronomy nerd, er, I mean, buff, you can keep tabs on some of the most fascinating astronomical happenings with the simple click of your mouse button. This article is the first in a series highlighting out-of-this-world tweets. Just don't expect follow-backs.

Did you know that NASA has a probe headed to Mercury? It's called MESSENGER, MErcury Surface, Space, ENvironment, GEochemistry, and Ranging. MESSENGER has already had two flybys of Mercury. The third and closest flyby is set for September 29, 2009. It will enter Mercury's orbit and become the first spacecraft to do so on March 18, 2011. Follow @MESSENGER2011.

A little closer to home, you can follow the Lunar Reconnaissance Orbiter (LRO for short). LRO "is leading NASA's way back to the moon." It's looking for potential landing sites, resources like water ice, and it's testing the long-term effects of exposure to lunar radiation. LRO is mapping the Moon's topography and studying its composition. Keep your eyes open for high definition images of the Apollo landing sites! Follow @LRO_NASA.

LRO is not alone up there. The Lunar CRater Observation and Sensing Satellite (LCROSS) is "confirming the presence or absence of water ice in a permanently shadowed crater at the Moon's South Pole." NASA's plan is to have LCROSS release two impactors on October 9, 2009. They will crash into the lunar surface to kick up material for LCROSS to fly through and analyze. "LCROSS will also provide technologies and modular, reconfigurable subsystems that can be used to support future mission architectures," whatever that means. Follow @LCROSS_NASA.

India has a lunar orbiter as well. Chandrayaan-1 is India's first mission to the moon. It was launched on October 2008 and it has been in orbit since November 12, 2008. Chandrayaan-1 is carrying a wide variety of instruments from countries all over the world. The mission objective is to map the lunar surface in 3-D, study the mineral and chemical makeup, search for water ice and carry out X-ray spectral studies. Chandrayaan-1 is the first of several missions India has planned. Follow @Chandrayaan1.

Moving to the Red Planet, Mars is crawling, literally, with rovers and is being orbited by probes. Spirit and Opportunity, or "Oppy" as it's affectionately called, have been slowly rolling over the Martian landscape since January 2004. They are on opposite sides of the planet but both are on the same mission: to find and analyze many rocks and soil samples looking for evidence of a watery past. Follow @MarsRovers.

Yet another rover on Mars is the Phoenix Mars Lander. While no longer active, the mission team is still releasing new data interpretations. Phoenix outlived its three-month expected life-span and returned amazing information. It found water ice in the Martian North Pole, and discovered soil chemistry and minerals that suggests Mars was once warmer and wetter. Follow @MarsPhoenix.

Circling above is the Mars Reconnaissance Orbiter, or MRO. While MRO doesn't have a Twitter account, a key piece of equipment on board does. HiRISE, HIgh-Resolution Imaging Science Experiment, is imaging Mars in extraordinary detail. Scientists can now view 1-meter-sized objects, which allows them to study the surface morphology more thoroughly. NASA says, "These new, high-resolution images are providing unprecedented views of layered materials, gullies, channels, and other science targets, in addition to characterizing possible future landing sites." Follow @HiRISE.

One of the most in-depth studies of a planetary system is coming from the Cassini-Huygens satellite and probe launched in October 1997. It arrived at Saturn on June 30, 2004. The mission was supposed to last only four years but Cassini is working overtime. The project has been extended until September 2010 and is now called the Cassini Equinox Mission. Cassini is making its way around the Saturnian system, with scheduled flybys of the fascinating moons Titan and Enceladus, as well as many of the icy moons. It's taking close looks at the rings and of course, orbiting and studying Saturn itself. if you only follow one of the probes or orbiters on this list, Cassini is the one. Follow @CassiniSaturn.

Even though Pluto has been, well, plutoed, NASA has a probe on its way out there. Launched in January 2006, New Horizons is set to explore Pluto, its moon Charon, and the Kuiper Belt beyond. Don't worry, you have plenty of time to catch up on the New Horizons news, it won't make it to Pluto until July 2015. It will begin its exploration of the Kuiper Belt in 2016 and it will spend four years encountering various objects. Follow @NewHorizons2015.

These nine space explorers are, or will be, collecting invaluable information about our solar system. Keeping tabs on them will give you new insights and knowledge about it, not to mention some really awesome pictures. Stay tuned for more astronomy on Twitter!

Sources:
NASA MESSENGER
NASA Lunar Reconnaissance Orbiter
NASA Lunar CRater Observation and Sensing Satellite
ISRO Chandrayaan-1
NASA Mars Rovers
NASA Mars Phoenix
NASA HiRISE
University of Arizona HiRISE
NASA Cassini
NASA New Horizons