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MCDONALD OBSERVATORY 9P/TEMPEL 1 DATA V1.0

Metadata Updated: August 22, 2025

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.

Access & Use Information

Public: This dataset is intended for public access and use. License: us-pd

Downloads & Resources

References

https://pds.nasa.gov

Dates

Metadata Created Date January 31, 2023
Metadata Updated Date August 22, 2025
Data Update Frequency irregular

Metadata Source

Harvested from NASA Data.json

Additional Metadata

Resource Type Dataset
Metadata Created Date January 31, 2023
Metadata Updated Date August 22, 2025
Publisher National Aeronautics and Space Administration
Maintainer
Identifier urn:nasa:pds:context_pds3:data_set:data_set.ear-c-lcs-5-9ptmpl1-spectra-v1.0_scq5-22rh
Data First Published 2021-05-21
Data Last Modified 2025-07-17
Category Earth Science
Public Access Level public
Data Update Frequency irregular
Bureau Code 026:00
Metadata Context https://project-open-data.cio.gov/v1.1/schema/catalog.jsonld
Schema Version https://project-open-data.cio.gov/v1.1/schema
Catalog Describedby https://project-open-data.cio.gov/v1.1/schema/catalog.json
Harvest Object Id 021b9272-6434-46a3-bf06-10b0c230832f
Harvest Source Id 58f92550-7a01-4f00-b1b2-8dc953bd598f
Harvest Source Title NASA Data.json
Homepage URL https://pds.nasa.gov/ds-view/pds/viewDataset.jsp?dsid=EAR-C-LCS-5-9PTMPL1-SPECTRA-V1.0
License http://www.usa.gov/publicdomain/label/1.0/
Program Code 026:005
Related Documents https://pds.nasa.gov
Source Datajson Identifier True
Source Hash 0515b9b956c5ffe2955d1c80778649bbddb8b4e0707afa1d9954e3d1a85e7a99
Source Schema Version 1.1

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