spacetoday.net: space news from around the webin association with SpaceNews


Impact may explain differences in Martian hemispheres
Posted: Fri, Jun 27, 2008, 7:21 AM ET (1121 GMT)
Mars giant impact model (UCSC) The large differences in terrain between the northern and southern hemispheres of Mars can be explained by a giant impact that took place on the Red Planet early in its history, scientists reported this week. The Martian southern hemisphere is primarily composed of rough, heavily cratered terrain, while the northern hemisphere is much lower and smoother, and may have once hosted an ocean of liquid water. In a set of papers published in Nature, scientists reported that this northern basin is most likely the remnant of a crater created when a giant object, between 1,600 and 2,700 kilometers across, collided with the planet at least 3.9 billion years ago. An impact model for the creation of the basin was first proposed many years ago, but discounted because the basin is elliptical, not circular, in shape. Better topographic data from orbiting spacecraft, as well as improved computer models of impacts, led scientists to reconsider the impact model.
<<previous article   next article>>
news in brief

SpaceX launches Indonesia communications satellite
Posted: Sun, Sep 14 4:07 AM ET (0807 GMT)

Soyuz launches Progress cargo spacecraft to ISS
Posted: Sun, Sep 14 4:06 AM ET (0806 GMT)

news links
Thursday, September 18
Rocket Lab Looks To Raise $750M In Share Sale
Aviation Week — 1:53 am ET (0553 GMT)
Update: SpaceX Launch from Vandenberg Rescheduled Due to Weather
Santa Barbara (CA) Edhat — 1:50 am ET (0550 GMT)


about spacetoday.net   ·   info@spacetoday.net   ·   mailing list