Mercury Craft Shows ''Spider,'' Asteroid Assaults

Mercury Image Show Volcanism, Asteroid Assaults
<< Previous   2 of 4   Next >>
Louise Prockter of Johns Hopkins University, a member of the MESSENGER science team, says she and her colleagues are mystified by a unique feature they're calling ''the Spider,'' seen above.

The formation lies in the middle of the large, 3.8-billion-year-old impact crater called Caloris Basin, and it consists of more than a hundred narrow troughs radiating from a complex central region.

The whole feature is raised off the floor of the basin. The scientists aren't sure whether the small crater near the center of the Spider has anything to do with its odd, raised shape.

One interpretation suggests that the troughs formed when materials in the Caloris Basin floor broke apart.

 More Photos in the News
 Today's Top 15 Most Popular Stories
 Free Email Newsletter: "Focus on Photography"
—Image by NASA/Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington
 
NEWS FEEDS    After installing a news reader, click on this icon to download National Geographic News's XML/RSS feed. After installing a news reader, click on this icon to download National Geographic News's XML/RSS feed.

Get our news delivered directly to your desktop—free.
How to Use XML or RSS




 

50 Drives of a Lifetime

Listen to your favorite National Geographic news daily, anytime, anywhere from your mobile phone. No wires or syncing. Download Stitcher free today.