New Small Comet Images--Oxygen Trails
The Polar spacecraft's high-resolution Earth Camera for ultraviolet wavelengths has discovered oxygen trails in the vicinity of Earth that are due to the disruption of some small comets as they approach our planet. These trails are distinquished from artifacts due to the penetration of energetic charged particles into the camera's sensors by a sequence of electronic shutter closings during the exposure period for the image. Thus a real oxygen trail is identified by alternate brightenings and dimmings along the trail. An energetic particle track will not have this distinctive fingerprint. Three examples of these oxygen trails are given here which have been superposed upon "Face of the Earth"TM maps of our planet.
|A long oxygen trail from the disruption of a small comet passes by Earth at large distances. This image was taken at 0207:39 UT on 28 August 1996 from a spacecraft altitude of 50,400 kilometers and geographic latitude and longitude 76.6° N and 180.5° E, respectively.|
|An oxygen trail passes above the Pacific Ocean toward the western coast of the United States. This image was taken at 0641:44 UT on 15 September 1996 from a spacecraft altitude of 47,400 kilometers and geographic latitude and longitude 85.7° N and 351.0° E, respectively.|
|This oxygen trail is located above San Diego, California. Such detections emphasize the need for further studies of the small comets. This image was taken at 0650:23 UT on 28 September 1996 from a spacecraft altitude of 27,300 kilometers and geographic latitude and longitude 50.8° N and 279.4° E, respectively.|
All data and images are provided courtesy of Dr. Louis A. Frank at the University of Iowa. Any use of these images must credit Dr. Louis A. Frank, The University of Iowa and NASA.