PIA00477: Venus - Possible Remnants of a Meteoroid in Lakshmi Region
 Target Name:  Venus
 Is a satellite of:  Sol (our sun)
 Mission:  Magellan
 Spacecraft:  Magellan
 Instrument:  Imaging Radar
 Product Size:  1633 x 1392 pixels (w x h)
 Produced By:  JPL
 Producer ID:  P38605
 Addition Date:  1996-11-26
 Primary Data Set:  Magellan MIDRs
 Full-Res TIFF:  PIA00477.tif (1.833 MB)
 Full-Res JPEG:  PIA00477.jpg (1.037 MB)

Click on the image above to download a moderately sized image in JPEG format (possibly reduced in size from original)

Original Caption Released with Image:

This full resolution mosaiced image covers an area of approximately 100 kilometers by 120 kilometers (62 by 74 miles) and is located in the Lakshmi region of Venus at 47 degrees north latitude and 334 east longitude. Due to the dense Venusian atmosphere, primary impact craters of less than a 3 kilometer (2 mile) diameter are nonexistent. The dark circular region and associated central bright feature in this image are thought to be the remnants of a meteoroid smaller than the size necessary to create an impact crater entering the atmosphere at a low velocity (approximately 350 meters/second.) The central bright feature appears to be a cluster of small secondary impacts, ejecta and debris from the original meteor that broke up in the atmosphere. Even though most of the meteorite did not hit the surface, the atmospheric shock wave could be great enough to modify the surrounding region. One explanation for this radar dark circular formation, called dark margins, could be that the shock wave was energetic enough to pulverize the surface (smooth surfaces generally appear radar dark.) Another explanation is that the surface could be blanketed by a fine material that was formed by the original meteor's breakup through the atmosphere. More than half of the impact craters on Venus have associated dark margins, and most of these are prominently located left of center of the crater. This is another effect which could be caused by the dense atmosphere of Venus.

Image Credit:
NASA/JPL

Image Addition Date:
1996-11-26