1.2 What’s New This Cycle

The following instruments will be offered in Cycle 20: two cameras on ACS: ACS/WFC and ACS/SBC, COS, FGS, STIS, and WFC3.

NICMOS is not offered for this Cycle. Please check the NICMOS Web site at: http://www.stsci.edu/hst/nicmos for current information.

•	Due to the heavy scheduling in Cycle 20, Large GO programs requesting 100 orbits or more in Cycle 20 must use the shorter target visibility values from Table 6.1, which will be enforced for any of these programs approved for Phase II.

Users are restricted to a maximum of 30 orbits per proposal on targets within each of the following RA intervals:

165 < RA < 205 degrees (11h00m < RA < 13h40m)

350 < RA < 75 degrees (23h20m < RA < 5h00m)

 

Please refer to Section 4.1.8 of the Call for Proposals for further information. The RA restrictions will apply to Cycle 20 only.

•	For WFC3 three new operational capabilities are available: spatial scans, charge injection for the UVIS CCDs, and greatly increased capacity of the Science Header Buffer (sometimes the limiting factor for subarray exposures per orbit). See Section 4.2 for additional details.

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For COS it is possible to observe with a new G130M central wavelength setting, 1222 Å. This setting spans the 1065-1365 Å bandpass, with resolving powers of R > 13,000 at 1135 Å and R > 10,000 at 1340 Å. This setting places the Ly alpha airglow line in the gap between detector segments A and B, eliminating this source of high intensity flux.