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HSTPAEC - HST Planned and Archived Exposures Catalog



This is the HST Planned and Archived Exposures Catalog (PAEC) as obtained from the Space Telescope Science Institute (STScI) Archive which created the original compilation from their Archive and Proposal databases. This database table provides a summary of all approved HST observations, including already completed observations and those which are planned to be executed as part of the current cycle or are reserved for execution by Guaranteed Time Observer (GTO) programs for the upcoming cycles.

This database table provides a summary of both planned and completed HST observations. Much more information can be obtained about each exposure, and the data themselves can be retrieved, using STScI's Multimission Archive (URL is or STScI's Archive Web Interface (URL is Note that a number of solar system and other objects have 0 values for their 2000 equinox RA and declination coordinates in the original HST table and hence also in this HEASARC database.

This HEASARC version of the HSTPAEC will be updated on a regular basis, usually within one month of the data files on the STScI Web site (URL being updated.


The HSTPAEC database table was last updated on 4 June 2017 and contains information on plannned and archived Hubble Space Telescope observations made through May 2017.


The original data files can be downloaded from the STScI Hubble Data Archive (HDA) at


This database table is recreated by the HEASARC on a routine basis, usually within one month of the PAEC data files at the STScI Hubble Data Archive (HDA) being modified.

Data Products

The single data product associated with the entries in this table is a GIF preview file available at the Space Telescope Science Institute HST Archive for which the HEASARC provides a link.


The HEASARC has added an additional field to this database table that is not present in the STScI database table. The proposal_exposure_id field is a simple numerical counter of the exposures, both planned and archived, that belong to each proposal ID. The values are assigned according to the order of the exposures in STScI's PAEC data files. This field was added so that multiple exposures of the same target with the same configuration and proposal ID could be uniquely identified.


The name of the target. In some cases, the name may have been truncated to 16 characters, which is the maximum space allowed for this field in this catalog.

The right ascension of the target in the default equinox.

The declination of the target in the default equinox.

The galactic longitude of the target.

The galactic latitude of the target.

The instrument configuration.

The instrument operating mode.

The apertures used. Multiple apertures are delimited by semicolons.

The spectral elements used. Multiple elements are delimited by semicolons.

The "central" wavelength of the observation, in Angstroms (AA).

A flag indicating whether corrective optics were used (i.e., COSTAR, WFPC2), where 'T' means that they were and 'F' means that they were not.

The length of the exposure time, in seconds.

The unique number assigned to each proposal.

This field has been added by the HEASARC to uniquely differentiate between multiple exposures of the same target in a given proposal.

The proposal cycle for the observation.

The dataset name, if the observation has been completed, will uniquely identify the data for the given exposure; otherwise, it will contain "PLANNED" if the observation has not yet been made.

The date on which the observation becomes/became public.

Contact Person

Questions regarding the HSTPAEC database table can be addressed to the HEASARC User Hotline.

Page Author: Browse Software Development Team
Last Modified: 19-Mar-2015