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Hubble Space Telescope

The HST General Observer proposal process is divided into two Phases. Phase I proposals contain a scientific justification and abbreviated technical specifications for review by the Telescope Allocation Committee in a particular Cycle. Phase II proposals provide many more technical details for programmes recommended by the TAC and approved by the STScI Director for implementation. The information required by proposers in Phases I and II is provided in the documents below.

The Latest Phase I Info Page Describing the Call for proposals and the Phase I proposal instructions.
Phase II Instructions Describing how to prepare and submit a Phase II proposal.
ACS Exposure Time Calculator The Exposure Time Calculator (ETC) is a web-based application developed in Python to assists Hubble astronomers and engineers in preparing Phase I and Phase II observing proposals. The ETC’s sole purpose is to calculate the Signal-To-Noise (SNR) Ratio for a given exposure time, or, calculate the Exposure Time for a give SNR Ratio.
ACS Dither Patterns A collection of useful ACS Dither Patterns. For the most up-to-date information, please refer to the Phase II Instructions.
WFC/ACS Post-Flash capability Cycle 21 A summary describing tests performed for WFC post-flash capability for mitigating CTE, with recommendations about its use in planning Phase II observations.