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After more than a dozen laps through the inner solar system, NASA's Messenger spacecraft will move into orbit around Mercury on March 17, 2011. The durable spacecraft - carrying seven science instruments and fortified against the blistering environs near the sun - will be the first to orbit the innermost planet.

The orbit insertion will place the spacecraft into a 12-hour orbit about Mercury with a 200 kilometer (124 mile) minimum altitude. At the time of orbit insertion, Messenger will be 46.14 million kilometers (28.67 million miles) from the sun and 155.06 million kilometers (96.35 million miles) from Earth.

Messenger has been on a six-year mission to become the first spacecraft to orbit Mercury. The spacecraft followed a path through the inner solar system, including one flyby of Earth, two flybys of Venus, and three flybys of Mercury. This impressive journey is returning the first new spacecraft data from Mercury since the Mariner 10 mission over 30 years ago.

Once in orbit successfully, Principal investigator Sean Solomon, of the Carnegie Institution of Washington, is hoping for some remarkable discoveries in the following months. "We started the Messenger mission as a proposal to NASA 15 years ago. We have been building for the orbit insertion and the observations that will follow for a decade and a half. To say that the science team is excited about what is to come is a huge understatement. We're really pumped."

The spacecraft is scheduled to remain in orbit for a year, allowing the probe to fly around Mercury 730 times. And if Messenger stays in good health and the funding allows, a one-year mission extension is likely to be granted.

The European and Japanese space agencies (Esa and Jaxa) are also sending a mission to Mercury this decade: Bepi-Colombo consists of two spacecraft - an orbiter for planetary investigation, led by ESA, and one for magnetospheric studies, led by JAXA.

This news item originally appeared on the NASA and BBC News websites.