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HST Duplication Checking

Use this page to check for duplications with your HST proposal.

Enter a proposal ID or your last name:
This form will check for possible duplications with your proposal. An observation is reported as a possible duplication if:
  • it comes from a proposal other than the one you're checking;
  • it is within 5 arcminutes of one of your observations;
  • it uses the same instrument as your observation;
  • it has been or will be executed in proposal cycles 7 through 16.

Please note: This interface does not yet contain the cycle 17 GTO reserved targets. For Cycle 17 GTO and ERS targets, please see the following pages:
The COS GTO Science Programs
The WFC3 Early Release Science Program

You may do more complex duplication-checking using the HST Duplication Checking form, or with the Proposed and Archived Exposures Catalog.

There is also a help page for these forms.