NASA, Johns Hopkins University of Applied Physics, Carnegie Institution of Washington on AP
The European Space Agency sends a mission to explore the mysteries of Mercury
BepiColombo, named after Italian mathematician and engineer Giuseppe "Bepi" Colombo, launched at 21:45. ET Friday aboard an Ariane 5 rocket from a spaceport in French Guiana
The spacecraft actually consists of two probes: one will go into orbit near the planet, while the other will be delivered by the Japan Aerospace Exploration Agency "You can look at the Mercury magnetic field from two different perspectives," says Nancy Chabot, a planetary scientist at Johns Hopkins University Applied Physics Laboratory. This gives a clearer picture of what changes during the 88 days Mercury takes to make one turn around the sun.
Mercury also has an unusual composition. Like the earth, it has a metal core. But Mercury's metal core occupies 80 percent of the planet.
"It can be thought of as a huge metal ball surrounded by a small boulder," says Chabot.
One of the most fascinating things about Mercury is that despite the fierce temperatures on the sunny parts of the planet – temperatures that can reach 800 degrees Fahrenheit – there are places in craters near the poles that never see the sun.
"In these permanently shaded regions," says Chabot, "It's cold enough that water ice is stable for billions of years."
Radar measurements from Earth first hinted that ice was on Mercury. At the beginning of this decade, NASA's Messenger mission confirmed that the ice was actually there.
But Messenger only got close enough to see the ice at Mercury's North Pole. The real icy action, says Chabot, is located at the South Pole.
"The largest crater for these water ice deposits is located directly on the south pole of Mercury," she says. "And I'm very excited that BepiColombo will be in orbit much closer to the southern hemisphere."
BepiColombo will take a rather complicated road to Mercury. It will fly once on Earth, twice on Venus and six times on Mercury, before it is in the right orientation to enter orbit around the innermost planet of our solar system. The entire journey will take a little over seven years.
And there is another Mercury feature about which Chabot is particularly curious.
"Messenger's crater," she says.
Chabot was one of the scientists in the Messenger team. When the spacecraft ran out of fuel, the mission leaders decided to send them to the planet, where a crater estimated at about 60 feet was created.
"Once BepiColombo gets into orbit, they should be able to reach the target area, take the highest resolution image they possibly have, and we might see the final resting place of Messenger."
It is more than a feeling that makes Chabot curious about the crash site. The effect of Messenger will undoubtedly have left a lot of trash.
"And maybe we could learn something about the freshly exposed material," she says. "So it's fun to believe that even in its demise, Messenger can help expand our knowledge of Mercury."