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Hubble Space Telescope
Late Breaking News

Changes since the Cycle 25 Call for Proposals has been Frozen

February 03, 2017

Proprietary Period Discrepancy in Call for Proposals, HST Primer and APT

In section 10.7 of the Cycle 25 Call for Proposals (CP) and section 7.2 in the HST Primer, the default proprietary period wasn't changed from 12 months to 6 months, as was changed in all other sections of the documents in the released version of the documentation. Today a new version of the CP and Primer were uploaded to fix this issue. The default proprietary period for Regular GO, Medium GO and Snapshot proposals in Cycle 25 is 6 months.

APT currently allows the selection of 12 months. Please do not select 12 months and justify this in the proposal. The options are only 0, 3 and 6 months as defined by the Call for Proposals. We hope to update APT with this change before the deadline. Any proposal submitted with 12 months will be flagged and changed to 6 months.

February 01, 2017

APT 25.0.3 has been Released

The Space Telescope Science Institute is pleased to announce the release of APT 25.0.3 and its associated documentation. This is the version of APT that needs to be used to support HST Cycle 25 Phase I submissions. This is also the version that should be used to support JWST Early Release Science (ERS) and Guaranteed Time Observers (GTO).

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 25 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..

Special Programs from Past Cycles

Status of Current and Past Programs:

Past Proposal Opportunities