Here is the apt file for GO/DD 10341, which should be executed as early in June 2004 as possible. All of the visits should be scheduled within 2 days. ----- Submission 57 (Sun May 16 07:07:44 GMT 2004) ----- I'm not sure what's going on. Measuring the D/H ratio in comets is one of the most important scientific objectives in planetary science. A comparison of the D/H ratio in comets to the value measured in the Earth's oceans can be used to assess whether cometary impacts contributed significantly to the delivery of water and other volatiles to the Earth. A comparison of the cometary ratio with the value in other solar system reservoirs (e.g., in the solar wind and the atmospheres of the Giant Planets), and to values observed in the interstellar medium, can be used to determine how primitive cometary matter is. Our recent detection of the deuterium Lyman-alpha line in C/2001 Q4 (NEAT) demonstrates that HST has a new and potentially important role to play in this exciting area of research. Fortuitously, another moderately bright comet, C/2002 T7 (LINEAR), is well-placed for HST observations in early June, and we request 8 orbits of HST time to measure deuterium in this comet. If our observations are successful, the number of comets for which D/H has been measured will be nearly doubled.

See the phase 1 submission. 0 false false false false false SUPPORTED SOLAR SYSTEM COMET LINEAR-2002T7 TYPE=COMET,Q=0.6146012966508876,E=1.000518914314327,I=160.5835486311661,O=94.85955637750945,W=157.7374511774273,T=23-APR-2004:01:28:53,EQUINOX=J2000,EPOCH=24-MAY-2004:00:00:00 SOLAR SYSTEM COMET LINEAR-2002T7-OFF TYPE=COMET,Q=0.6146012966508876,E=1.000518914314327,I=160.5835486311661,O=94.85955637750945,W=157.7374511774273,T=23-APR-2004:01:28:53,EQUINOX=J2000,EPOCH=24-MAY-2004:00:00:00 TYPE=POS_ANGLE,RAD=700.0,ANG=0.0,REF=SUN false false false false false false false false