Hubble Space Telescope Observations of 19P/Borrelly During the DS1 Flyby

Details Hubble Space Telescope Observations of 19P/Borrelly During the DS1 Flyby Hubble Space Telescope Observations of 19P/Borrelly During the DS1 Flyby

Dec 2001

adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2001dps....33.5806w&link_type=abstract

American Astronomical Society, DPS Meeting #33, #58.06; Bulletin of the American Astronomical Society, Vol. 33, p.1561

Astronomy and Astrophysics

Astronomy

Scientific paper

In support of the Deep Space 1 (DS1) flyby of Comet 19P/Borrelly on UTC 22.938 September 2001, we employed the Space Telescope Imaging Spectrograph (STIS) on the Hubble Space Telescope (HST) to obtain mid- and far- ultraviolet (UV) spectra of the comet, along with contemporaneous high-resolution optical images. HST/STIS observations were made both before (UTC 21.653-21.884 September; r=1.361 AU, Δ =1.478 AU, r-dot=+1.22 km/sec, and phase angle=41.2 deg) and after (UTC 23.459-23.891 September; r=1.362 AU, Δ =1.469 AU, r-dot=+1.56 km/sec, and phase angle=41.3 deg) the time of DS1's closest approach to the nucleus. Based on analysis of the spatial brightness profile for the OH(0,0) band, we derive a preliminary value of Q(water)=(4.0+/-0.5) x1028 molecules/sec, but the observed OH spatial profile is clearly asymmetric and is somewhat flatter than predicted by the model. The peaks of both the OH and CS(Δ -v=0) spatial brightness distributions are significantly displaced from the position of the continuum peak, roughly by 0.5"=535 km in projection. The projected solar vector was at 45 deg to the long axis of the slit, and the emissions are brighter in the sunward-facing hemisphere. A conventional model in which CS is the daughter of CS2 produces a spatial profile which is much narrower than that observed when using the nominal CS2 lifetime of τ =500 sec (at r=1 AU). For τ =500 sec, we derive Q(CS2)=2.5x1025, while for τ =1000 sec we obtain Q(CS2)=4x1025. Thus, CS2/H2O 0.0006--0.001, which is in the ``normal" range (Meier & A'Hearn, Icarus, 125, 164-194,1997). Both the OH and CS spatial profiles are somewhat ``flatter'' than expected, and this may imply an ``extended source" for their parents (i.e., not all of the H2O and CS2 sublimate directly from the nucleus). The offsets between the gas and dust spatial brightness profiles could be related to the offsets measured in the ion distribution by PEPE aboard DS1.

Affiliated with

Also associated with

No associations

Rating

Hubble Space Telescope Observations of 19P/Borrelly During the DS1 Flyby does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Hubble Space Telescope Observations of 19P/Borrelly During the DS1 Flyby, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Hubble Space Telescope Observations of 19P/Borrelly During the DS1 Flyby will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFWR-SCP-O-1102950