European spacecraft set to unravel mysteries of Mercury

A UK-built spacecraft will set off for Mercury this week in a first mission of its kind to determine if the nearest planet to the Sun contains water.

The European Space Agency's (ESA) BepiColombo mission will send two orbiters to explore the fiery world where the surface temperatures reach about 450 degrees Celsius. "There are some interesting quirks about Mercury that we still don't understand," said Professor Emma Bunce from the University of Leicester in the UK, which built one of the instruments on board.

The mission is hoped to answer questions raised by the previous missions such as whether the planet holds water, 'The Telegraph' reported. Despite being very close to the Sun, the tilt of Mercury means some areas are permanently in shade and temperatures can fall to minus 180 degrees Celsius, allowing ice to form on the planet.

Researchers also want to learn more about Mercury's magnetic field. It was thought that the planet was solid all the way through; however, previous missions discovered a magnetic field suggesting it may have a molten interior.

Till now, only two spacecraft have been to Mercury, NASA's Mariner 10 which flew past the planet in 1974 and 1975 and the US space agency's Messenger which orbited the planet between 2011 and 2015. "Messenger told us a great deal but also raised more questions," Bunce was quoted as saying.

The spacecraft will launch from the European Spaceport in Kourou, French Guiana, on October 20 and will take seven years to reach Mercury arriving in 2025.

During its 5.2 billion miles journey it will make a complex series of fly-bys of Earth, Venus and Mercury to help it slow down enough to avoid the huge gravitational pull of the Sun.