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

• 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.