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Hubble Space Telescope
Late Breaking News

Changes since the Cycle 25 Call for Proposals has been Frozen

January 25, 2018

HST Cycle 25 Mid-Cycle 2 Proposal Deadline Changed

The next Deadline for Cycle 25 Mid Cycle Proposals is now March 21, 2018. Please see the Mid Cycle Page for more details.

August 28, 2017

HST Cycle 25 Long Range Plan has been Released

As announced in the Cycle 25 Call for Proposals, the programs accepted by the Cycle 25 TAC will be implemented over an 18-month nominal duration, extending into Cycle 26. In addition, there is a Cycle ‘tail' that can extend a further 6 months for observations having restrictive scheduling constraints or subscription conflicts with other activities in the nominal Cycle period. The current Long Range Observing Plan is fully subscribed through at least April 2019. A large fraction of the observations are highly constrained and therefore have limited flexibility for when they can be executed. We know that some PI’s with observation plan windows in 2019 will be disappointed that their data cannot be obtained sooner. However, please be aware that every effort has been made to ensure maximum efficiency and equitable use of the observatory on behalf of the HST community.

Please also be aware that the Long Range Plan is continually evaluated to ensure that observatory efficiency remains as high as possible. Changing science and observatory events may open up opportunities for us to move observations forward in the plan. HST planners are vigilant to identify observations that can take advantage of those opportunities and move them early whenever possible. Beyond that, PIs may submit requests to the Telescope Time Review Board (TTRB) for changes in program execution plan windows, but only with a strong scientific justification for doing so. Thank you for your understanding and patience.

March 30, 2017

Policy Clarification for Target of Opportunity Observations in Cycles 25 and 26

Small Target of Opportunity (ToO) programs will not be available via the Cycle 26 Call for Proposals. Proposals to be implemented in Cycle 26 should be submitted by the April 7 Cycle 25 deadline. As with previous cycles, we expect to allow 8 disruptive ToOs + one ultra-disruptive ToO in Cycle 25, and an additional 8 + 1 in Cycle 26 from this one pool of orbits.

March 24, 2017

HST observations to detect plumes/outgassing from Europa

The STScI Director has commissioned a committee to provide advice on optimizing future strategies for using Hubble to investigate potential outgassing from Europa. The committee is currently developing recommendations that will include suggestions for pilot observations in the near future. The full report will not be available until after the Cycle 25 proposal deadline. Consequently, interested parties should not submit proposals at this time unless the observations must be executed before October 27 2017. Time will be set aside for observations at later dates, and proposals related to the Europan plumes will be solicited as part of the first Cycle 25 Call for Mid-Cycle proposals, deadline September 30 2017.

March 21, 2017

Small proposals Cycle 25 vs 26

The Call for Proposals section 1.3 states "With this, the Cycle 25 solicitation, we invite investigators to propose for Small GO programs for Cycle 26." Questions have been raised about how this will be handled:

  • Is there a separate template for Cycle 26?
  • Does our Cycle 25 small GO proposal also count for Cy 26?
  • Do we need to submit 1 proposal or 2 for consideration for both?
  • Is there a place on the template to indicate that I want it considered for both?
You should submit one proposal and it will be considered for one pool of orbits. We're basically separating the selection process from the scheduling. We're allocating extra orbits to the panels and they will rank the proposals, as in the normal TAC. Since they have more orbits, they will recommend more proposals. We will assign proposals to cycle 25 or 26 when we develop the long range plan and see where they schedule.

March 17, 2017

APT 25.0.4 has been Released

The Space Telescope Science Institute is pleased to announce the release of APT 25.0.4 and its associated documentation. The bulk of the work was for JWST. People working on HST Phase I do not have to download this new version. APT 25.0.4 should be used for GTO development. Either version can be use for HST Cycle 25 Phase I Submissions.

March 10, 2017

Policy Update for Snapshot Programs in Cycle 25 and 26

SNAP programs will not be available via the Cycle 26 Call. Consequently, a larger number of SNAPs will be allocated by the Cycle 25 TAC. In particular, the number of spectroscopic COS and STIS-MAMA Snaps (other than those using the NUV-Prism) will be capped at 250, rather than 150.

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 most other sections of the documents in the released version of the documentation. A new version of the CP and Primer was uploaded to fix this issue. Pure Parallel Proposals as stated in section 4.2.2 on page 49 is also incorrect and hasn't been corrected. The default proprietary period for Regular GO, Medium GO, Regular or Medium Pure Parallel 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. 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. Go to the CP.

    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. Go to the Primer.

    Science Justification Templates for Cycle 27 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