Menu: Skip within this page



MPC Home

MPC Annex


The MPC Users' Group (MUG) invites community feedback on any issues, concerns, or questions about the MPC.


Please provide feedback on the SBN website.

PDS Support

McDonald Observatory 9P/Tempel 1 Spectral Observations

A PDS3 version of this data set can be found here.


Abstract: We report on low-spectral resolution observations of comet 9P/Tempel 1 from 1983, 1989, 1994 and 2005 using the 2.7m Harlan J. Smith telescope of McDonald Observatory. This comet was the target of NASA's Deep Impact mission and our observations allowed us to characterize the comet prior to the impact. In the published paper, we showed that the comet decreased in gas production from 1983 to 2005, with the decrease being different factors for different species. OH decreased by a factor 2.7, NH by 1.7, CN by 1.6, C3 by 1.8, CH by 1.4 and C2 by 1.3. Despite the decrease in overall gas production and these slightly different decrease factors, we found that the ratios of the gas production rates of OH, NH, C3, CH and C2 that of CN were constant over all of the apparitions. We saw no change in the production rate ratios after the impact. We found that the peak gas production occurred about two months prior to perihelion. This data set represents the integrated fluxes and column densities, mentioned in the published paper, which were used to derive the production rates in the paper. These data were migrated from the PDS3 dataset EAR-C-LCS-5-9PTMPL1-SPECTRA-V1.0.

urn:nasa:pds:gbo-mcdonald:lcs-9p::1.0 MD5 Checksums Browse Download (732.5 KB)

Citation to use when referencing this PDS4 collection: "Cochran, A. L., Barker, E. S., Caballero, M. D., Gyorgey-Ries, J., McDonald Observatory 9P/Tempel 1 Spectral Observations (PDS4 Format), urn:nasa:pds:gbo-mcdonald:lcs-9p::1.0, NASA Planetary Data System, 2019."

This PDS4 collection is a part of the following PDS4 bundle:

urn:nasa:pds:gbo-mcdonald::2.0 Groundbased Observations at McDonald Observatory Browse

Useful links: