WASHINGTON: A Nasa spacecraft began orbiting Mars on Sunday, on a mission to study how the Red Planet’s climate changed over time from warm and wet to cold and dry.

The unmanned orbiter has travelled more than 10 months and 711 million kilometres to reach Mars for a first-of-its kind look at the planet’s upper atmosphere.

“Wow, what a night. You get one shot with Mars orbit insertion and MAVEN nailed it tonight,” said project manager David Mitchell.

The data from the Mars Atmosphere and Volatile Evolution (MAVEN) spacecraft aims to help scientists understand what happened to the water on Mars and the carbon dioxide in its atmosphere several billion years ago.

How Mars lost its atmosphere is one of science’s biggest mysteries. The answers could shed light on the planet’s potential to support life — even if that was just microbial life — long ago.

The spacecraft’s findings are also expected to help add to knowledge of how humans could survive on a future visit to the planet, perhaps as early as 2030. “Mars is a cool place, but there is not much atmosphere,” said John Clarke of the MAVEN science team.

“It is very cold, it is well below zero. The atmosphere is about half a per cent of what we are breathing,” he added.

But we know that Mars could change and it was probably different in the past. There is a lot of evidence of flowing water on the surface from Mars’s ancient history.”

Mission begins: The spacecraft will now enter a six-week phase for tests.

It will then begin a one-year mission of studying the gases in the planet’s upper atmosphere and how it interacts with the sun and solar wind.

“We are looking at early November as the official start of science,” said principal investigator Bruce Jakosky.

Much of MAVEN’s year-long mission will be spent circling the planet 6,000 kilometres above the surface.

Published in Dawn, September 23rd, 2014