The MAVEN spacecraft arrived at its destination, Mars, and is now in orbit around the planet, NASA reports, joined by coverage on CNN.
The 442 million-mile journey to the red planet began on Nov 18, 2013, and on Sept 21 at 9:50 PM EDT, right on schedule, engineers at the Goddard Space Flight Center in Greenbelt, Md., fired the craft’s main engines for 33 minutes and 26 seconds. MAVEN is an acronym for Mars Atmosphere and Volatile Evolution, and its journey had been in progress for 307 days at that point. Orbit within the gravitational field of Mars was achieved at 10:34 PM.
The satellite will collect detailed data about the Martian surface and magnetic field. There’s evidence of water on Mars—the so-called outflow channels, flooding, rivers, and even large oceans—but except for possible water trapped under the ice caps at its poles, the surface of Mars is completely dry at this point.
Two separate theories have been advanced about how water existed on Mars in the first place, a cold-planet theory and a warm-planet theory. But whatever theory you subscribe to, Mars must have had an atmosphere to keep the water trapped in.
The planet’s atmosphere today, which is made up almost entirely of carbon dioxide, must be much thinner than it was when the surface was wet, causing any water that existed on the surface to evaporate into space. The big question for the MAVEN science team is, How’d all the water get out?
Several teams in addition to MAVEN—teams of scientists using rovers (Curiosity, Opportunity) and satellites (Odyssey, Mars Reconnaissance Orbiter)—are trying to determine what happened to the atmosphere on Mars. MAVEN has already started collecting data, but the science side of its mission will begin in earnest sometime in November. Then, we may be able to consider the questions that formed the basis for spending some $671 million to send MAVEN to Mars: Was the Martian atmosphere like Earth’s is today? Can we predict the future of Earth’s atmosphere by studying what happened on Mars?
“We’re trying to understand the context in which life might have existed” on Mars, the Baltimore Sun quoted Bruce Jakosky of the University of Colorado, Boulder, the mission’s principal investigator, as saying in a news conference. “By understanding the processes by which the atmosphere changed, we’re understanding the history of the habitability of Mars.”
The Sun also reported that Comet C/2013 A1 (Comet Siding Spring), will graze the Martian atmosphere on Oct 19. It will fly within 82,000 miles of MAVEN and give researchers a close look at what happens when a comet’s trail envelops a planet’s atmosphere. No modern comet has ever flown that close to Earth.
What was the average speed, in mph and km/h, of MAVEN’s journey to Mars? See Common Core sixth-grade math standard EE.A.2.C for more information.
