During a week of not-so-great news in the world (to understate things by quite a lot) it’s nice to report something good: the MESSENGER spacecraft has successfully established orbit around the planet Mercury, beginning its new 12-month mission of mapping and researching the innermost planet of our solar system!

After traveling nearly 5 billion miles over the course of 6.5 years, MESSENGER has achieved what no spacecraft before has done. Mercury is now the final “classical” planet to be orbited by a manmade spacecraft, as well as the last of the inner planets to currently have an active orbiting research satellite of some sort.

“Achieving Mercury orbit was by far the biggest milestone since MESSENGER was launched more than six and a half years ago. This accomplishment is the fruit of a tremendous amount of labor on the part of the navigation, guidance-and-control, and mission operations teams, who shepherded the spacecraft through its 4.9-billion-mile  journey.”

– Project Manager Peter Bedini, APL

At 9:45 pm EDT this evening, after completing various burn maneuvers to enter orbit, MESSENGER rotated its antenna back to face Earth and returned data confirming success.

Over the next few weeks mission engineers will be checking systems on the spacecraft, and on March 23 the instruments will be activated. The main science phase of the mission will commence on April 4.

Images from MESSENGER in orbit won’t be arriving until at least the end of March. (So we will have to be patient!)

MESSENGER’s orbit about Mercury is highly elliptical, 200 kilometers (124 miles) above the surface at the lowest point and 15,193 kilometers (9,420 miles) at the highest.

The Planetary Society issued a statement this evening, in which Executive Director Bill Nye (a.k.a. “The Science Guy”) said:

“MESSENGER is orbiting Mercury! It’s rocket science at its best. Before this success, Mercury was the only inner planet that had never been orbited by a spacecraft.”

And as of today that is no longer the case. Congratulations to everyone on the MESSENGER team!

Read the official press release on the mission site, or the article on Universe Today for more info.

Also, check out this wonderful video by YouTube user nasagogblog showing some great photos from the MESSENGER mission, from assembly and launch to its previous three flybys of Mercury!

Looking forward to the next 12 months of discovery – with the possibility of a mission extension as well! 🙂

Image credits: NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington