U of A contributes to eye on Mercury

(Edmonton) When news broke that NASA's Messenger spacecraft finally entered orbit around Mercury no physics researchers could have been happier than the University of Alberta's Robert Rankin and Jan Paral.

Since the observation satellite launched from Earth in 2004, Rankin, a U of A physics professor, and Paral, a PhD student, have been involved with the mission. The two spent months building computer models of the atmosphere Messenger would encounter at Mercury.

Rankin says their calculations were proven correct. "It took six years for Messenger to get in the vicinity of Mercury," said Rankin. "On the fly-bys and approach to the planet, instruments detected a heavy presence of sodium gas, just as we had modeled."

Although Rankin and Paral are not official NASA investigators on the Messenger mission, they plan to work closely with the agency's team assigned to analyzing Mercury's atmosphere.

Rankin says Mercury has puzzled researchers since the 1970's, the last time a satellite got close to Mercury. In 1974, NASA's Mariner 10 detected a magnetic field around Mercury similar to Earth's. "We can't live without our magnetic field. It blocks lethal space radiation from reaching Earth and Mercury's magnetic field plays a similar role," said Rankin.

Rankin says that's why it's vital that we understand the chemical composition of other planets.

It took enormous computer power for the U of A team to build atmospheric models for Mercury. Paral travelled to upstate New York and tapped into IBM's now-famous Watson laboratory. The Watson lab and its BlueGene supercomputers were recently featured in a human-versus-machine competition of general knowledge on the popular TV game show, Jeopardy. IBM won.

Paral says that computing power helped develop a detailed profile of the gases and chemicals surrounding a planet that's 154 million kilometres away from the reams of data gathered by earlier observational space satellites.

"I look at Mercury as a laboratory for studying Earth," said Paral. "Mercury is smaller and less complicated, but we can look at all of its components-the magnetic field, its gravity and even its liquid core-to discover new things about our planet."

Rankin says the next few years will be exciting for he and Paral.

"It's expected that Messenger will be feeding back data until sometime next year," said Rankin. "We hope to be involved all the way along in figuring out Mercury's secrets."