Phase I Proposing

At this point you should have assembled all the information you need to submit your Phase I HST observing-time proposal. During the course of this process you should review the items listed below.

For All Proposals:

• Check the catalog of previously executed and accepted programs to search for any duplications, and if present, provide a justification for duplicate observations.
• Justify any special requirements (e.g., SHADOW, interactive acquisition, CVZ, target-of-opportunity, time-critical scheduling, or the re-use target capability).
• Consider any special calibrations (e.g., unusually accurate wavelength determination requiring additional (non-automatic) wavecal exposures, fringe flats, or slitless spectroscopy), and account for their time in your request.
• Check your exposure times and configurations to ensure they are sufficient to provide the desired signal-to-noise ratios and accuracies, without saturation.
• Allocate time for a target acquisition with appropriate centering accuracy. If a pre-acquisition image is needed, include the necessary extra orbit in the total orbit-time request.
• Consider the need for, and benefit of, obtaining coordinated parallel exposures with other instruments. Take into account any applicable data volume restrictions.
• Include all applicable overheads so that in Phase II you will have enough orbits available to successfully implement your observations.
• If applicable, justify the use of any available-but-unsupported modes, and explain how you plan to deal with calibration issues.
• Check the Phase II web page for any updates. You can also find there instructions for requesting changes to your program and observing policies.

For CCD Observations:

• Check that you are not exceeding the CCD full well counts pixel^-1 limit for pixels (emission lines or objects) of interest.
• Allow time for CR-SPLIT observations and dithering, as needed.

For MAMA Observations:

• Check that your source does not exceed the absolute bright-object count-rate limits for MAMA exposures. For target-of-opportunity programs, explain how you plan to show that the target does not exceed the bright object limits.
• Check that you are not exceeding the MAMA 65,536 counts pixel^-1 buffer- imposed limit over pixels (emission lines or objects) of interest.
• Check that no MAMA visit is longer than 5 orbits.
• Justify the need for both MAMA and CCD scientific exposures in a single visit, or have allowed sufficient orbital time to allow separation of MAMA and CCD science exposures, if applicable.
• If early acquisition images in support of MAMA bright object checking are necessary, they must be included in the Phase I orbit request.

Phase I Orbit-Allocation Examples

A sample Phase I orbit-allocation worksheet is presented in the Phase I Proposal Instructions. Examples of Phase I orbit estimations are worked through in this Handbook (see Examples Used in this Handbook, Exposure Time Examples, and Orbit Use Determination Examples).