Latest Caloris Basin Stories

The solar system's innermost planets are about to put on a beautiful show.This week, Mercury is emerging from the glare of the sun and making a beeline for Venus. By week's end, the two planets will be just 3o apart, an eye-catching pair in the deep-blue twilight of sunset.The best nights to look are April 3rd and 4th. Go outside at the end of the day and face west. Venus pops out of the twilight first, so bright it actually shines through thin clouds. Mercury follows, just below and to the...

As NASA's MESSENGER spacecraft prepares for its second flyby of Mercury, new analyses of data from the first flyby will be presented at the European Planetary Science Congress in Münster on Tuesday 23rd September.Dr Sean Solomon, MESSENGER's Principal Investigator, will present a model that suggests that the origin of the Pantheon Fossae, a radiating web of troughs located in the giant Caloris Basin, is directly linked to an impact crater at the centre of the web.The Caloris Basin is the...

Scientists have argued about the origins of Mercury's smooth plains and the source of its magnetic field for more than 30 years. Now, analyses of data from the January 2008 flyby of the planet by the Mercury Surface, Space Environment, Geochemistry and Ranging (MESSENGER) spacecraft have shown that volcanoes were involved in plains formation and suggest that its magnetic field is actively produced in the planet's core. Scientists additionally took their first look at the chemical...

The surprises continue. Scientists studying the harvest of photos from the MESSENGER spacecraft's Jan. 14th flyby of Mercury have found several craters with strange dark halos and one crater with a spectacularly shiny bottom."The halos are really exceptional," says MESSENGER science team member Clark Chapman of the Southwest Research Institute in Boulder, Colorado. "We've never seen anything like them on Mercury before and their formation is a mystery."Consider the...

After a journey of more than 2.2 billion miles and three and a half years, NASA's MESSENGER spacecraft made its first flyby of Mercury just after 2 PM Eastern Standard Time on January 14, 2008. All seven scientific instruments worked flawlessly, producing a stream of surprises that is amazing and delighting the science team. The 1,213 images conclusively show that the planet is a lot less like the Moon than many previously thought, with features unique to this innermost world. The puzzling...

"Discoveries are at hand!" That's what members of the MESSENGER science team are saying after their spacecraft flew past Mercury on Jan. 14th at a distance of only 124 miles. The historic flyby netted 500 megabytes of data (now safely downloaded to Earth) and more than 1200 photos covering nearly six million square miles of previously unseen terrain."We're inundated with data"”it's wonderful," says mission scientist and planetary geologist Scott Murchie of the Johns...

When Mariner 10 flew past Mercury three times in 1974 and 1975, the same hemisphere was in sunlight during each encounter. As a consequence, Mariner 10 was able to image less than half the planet. Planetary scientists have wondered for more than 30 years about what spacecraft images might reveal about the hemisphere of Mercury that Mariner 10 never viewed.On January 14, 2008, the MESSENGER spacecraft observed about half of the hemisphere missed by Mariner 10. This image was snapped by the...

NASA will return to Mercury for the first time in almost 33 years on January 14, 2008, when the MESSENGER spacecraft makes its first flyby of the Sun's closest neighbor, capturing images of large portions of the planet never before seen. The probe will make its closest approach to Mercury at 2:04 p.m. EST that day, skimming 200 kilometers (124 miles) above its surface. This encounter will provide a critical gravity assist needed to keep the spacecraft on track for its 2011 orbit insertion...