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Hubble Space Telescope
Current and Previous Cycle Results

Mid Cycle 23 Results
Cycle 24 Results
Cycle 24 Joint HST/XMM Results from the XMM Review Fall 2015
Multi-Cycle Treasury Program Information
These catalogs are all generated from the submitted Phase I proposals. The official Phase II Catalogs are maintained at the Archive website and are created after Phase II submission. You can find the Abstracts, Titles and Planned and Archived Exposure Catalogs at:

Past Programs (Cycle 6 - 23)

Release Documents

    The Call for Proposals describes the policies and procedures for submitting a HST Phase I proposal. Get the CP as: PDF [US Letter Size], PDF [A4 Size], or as HTML.

    The Primer provides an introductory overview of the Hubble Space Telescope and explains how to calculate the appropriate number of orbits for an observing proposal. Get the Primer as: PDF [US Letter Size], PDF [A4 Size], or as HTML.

    Science Justification Templates for Cycle 24 HST Phase I

  • Full Set of HST Documentation

HST Phase I Roadmap

    The Roadmap is a step-by-step guide to proposing and submitting an HST proposal. Download APT here.

DD Time

Up to 10% of the available HST observing time may be reserved for Director's Discretionary (DD) allocation.

Mid-Cycle Proposals

Up to 200 orbits per cycle will be available for Mid-Cycle GO programs. Mid-Cycle programs were initiated in Cycle 23 to provide the community with an opportunity to propose for in-cycle observations of recently-discovered, non-variable objects. As such, they complement Director’s Discretionary programs, which target unexpected transient phenomena and time-critical observations..

Past Proposal Opportunities