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Hubble Space Telescope

Electronic Document Formats

The Call for Proposals and HST Primer are (only) available electronically in HTML and PDF formats. The HTML version is optimized for on-line browsing, and contains many links to related or more detailed information, both within the document itself and within other STScI documents. You are therefore encouraged to use the HTML version electronically. Nonetheless, some people may prefer to read a hardcopy, and with this in mind, the PDF version was optimized for printing.

Printing the Documents

If you wish to print either document, we recommend that you use the PDF version. PDF documents are provided in both US Letter Size format and in European A4 Size format. Please choose the format appropriate for your printer. Any links to information on the internet will appear as underlined text in the hardcopy print. You can look up the internet address of the corresponding link in Appendix E (Call for Proposals) or Appendix D (HST Primer).

Browsing the HTML Document

You can consult the HTML versions of the documents using your favorite internet browser. Depending on your browser, you may obtain a nicer layout if you instruct your browser to use its default fonts, instead of the document-specific fonts.

Netscape users who want to override document specific fonts should take the following steps:

(a) choose `Preferences' from the `Edit' menu;
(b) Choose `Appearance' from the pop-up menu, and then `Fonts';
(c) Mark the setting `Use my default fonts, overriding document-specific fonts';
(d) click `OK'.

Users of other browsers should consult the documentation for their browser, if necessary.

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