Mercury as it appears to the human eye (l) and in false-colour to reveal different surface features
The planet Mercury is far more active than first thought with magnetic twisters which dance across its surface, scientists revealed today.
Nasa’s Messenger spacecraft flew past the rocky world last October and took close-up images of a third of the planet’s surface for the first time.
‘This second Mercury fly-by provided a number of new findings,’ said Sean Solomon, the probe’s principal investigator from the Washington-based Carnegie Institution.
‘One of the biggest surprises was how strongly the dynamics of the planet’s magnetic field-solar wind interaction had changed from the first Mercury fly-by in January 2008.’
The photos also revealed a previously unknown mammoth crater that spanned 430miles – the equivalent distance from Brighton to Edinburgh.
The Messenger craft took more than 1,200 high-resolution images on its most recent fly-by
The ‘Rembrandt’ impact basin is well exposed and is the first geological feature found not to be covered by a thick layer of volcanic ash.
‘This basin formed about 3.9billion years ago, near the end of the period of heavy bombardment of the inner solar system,’ said Thomas Watters from the Smithsonian Institution in Washington.
Experts said it showed evidence of concentrated volcanic and deformational activity.
Mercury has remained largely a mystery to Earth’s scientists despite being a close neighbour. This is because probes have to overcome the Sun’s enormous gravitational pull as well as very high levels of radiation. The surface temperature reaches a sizzling 350C during the day.
The Messenger craft was the first probe to visit the diminutive world since the Marine 10 spacecraft’s visit in the 1970s. Before its visit half of the planet’s surface was unknown.
On October 6, 2008, Messenger soared just 125miles above the planet’s equator at a speed of 14,800miles per hour taking more than 1,200 images.
Messenger’s first flyby in January 2008 revealed that volcanic eruptions produced many of Mercury’s expansive plains and that its magnetic field appears to be actively generated in a molten iron core.
The probe is on course to make its third flyby on September 29 this year.
Via Daily Mail