Computer Science
Scientific paper
Jul 1994
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1994hst..prop.5713w&link_type=abstract
HST Proposal ID #5713
Computer Science
Hst Proposal Id #5713 Interstellar Medium Absorption Lines
Scientific paper
We request time on the HST to obtain high-resolution (20 km/s) spectra around the 2800A MgII doublet of two stars and one quasar which lie projected toward the high-velocity HI cloud complex A. The prime purpose of this project is to determine the distance to complex A. Using these spectra we will be able to derive for the first time a firm upper or lower distance limit of 2.5 kpc for a HVC, which allows us to exclude several of the many proposed explanations. If we find that the object is beyond 2.5 kpc this will have important implications for the understanding of the structure of the Galaxy, especially for the energy balance and dynamics of interstellar matter and the exchange of material between the halo and the disk. A byproduct of the observations will be the first measurement of the MgII abundance in a HVC. Metal abundances are important for the problem of the origin of HVCs. We discuss the principle and problems of the method used to estimate distances and describe the current status of knowledge. Ground-based observations have been limited by sensitivity and ST allows us to reach stars faint enough so that a clear answer can be found.
No associations
LandOfFree
The Distance of High-Velocity Clouds 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 The Distance of High-Velocity Clouds, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The Distance of High-Velocity Clouds will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-820056