Hubble Cycle 19 Proposal Selection

Rachel Somerville, Claus Leitherer,, & Brett Blacker,


When the Cycle 19 Call for Proposals was released in December 2010, Hubble had already seen a full cycle of operation with the newly installed and repaired instruments calibrated and characterized. The Advanced Camera for Surveys (ACS), Cosmic Origins Spectrograph (COS), Fine Guidance Sensor (FGS), Space Telescope Imaging Spectrograph (STIS), and Wide Field Camera 3 (WFC3) were all close to nominal operation and were available for Hubble observing proposals in Cycle 19. The Near Infrared Camera and Multi-Object Spectrometer (NICMOS) was available for proposers as well. However, when the Call for Proposals was issued, the decision on when the NICMOS cooling system would be restarted had not yet been made, and the instrument was inactive. Nevertheless, the proposers were advised to assume NICMOS would be available during Cycle 19.

The Phase I deadline for Cycle 19 was February 25, 2011. As usual, although some proposals were submitted weeks before the deadline, the majority arrived on the last day, with a rapid rise in submission rate as the deadline, 8 p.m. Eastern time, approached. Due to power issues in Baltimore, Maryland, the deadline was extended incrementally: from 8 p.m. to 10 p.m. on 2/25; then from 10 p.m. on 2/25 to 3 p.m. on 2/26; and then from 3 p.m. to 6 p.m. on Saturday 2/26 (the final deadline).

We received a total of 1,007 proposals, after accounting for duplications and withdrawals.

Review process

Members of the international astronomical community review Hubble proposals. Grouped in panels organized by science category, each panel has one or more “mirror” panels to enable transfer of proposals in order to avoid conflicts. In Cycle 19, the panels were divided into the categories of Planets, Stars, Stellar Populations and Interstellar Medium (ISM), Galaxies, Active Galactic Nuclei and the Inter-Galactic Medium (AGN/IGM), and Cosmology, for a total of 14 panels. One of these panels reviewed Regular Guest Observer, Archival, Theory, and SNAP proposals.

The panel chairs also serve as members of the Telescope Allocation Committee (TAC), which reviews Large and Archival Legacy proposals. In addition, there are three at-large TAC members, whose broad expertise allows them to review proposals as needed, and to advise panels if the panelists feel they do not have the expertise to review a certain proposal.

The process of selecting the panelists begins with the selection of the TAC Chair, about six months prior to the proposal deadline. James Graham (UC Berkeley) served as Chair of the Cycle 19 TAC. Next, we select the chairs of the panels and the at-large members. The recruitment of panel members is usually completed about two months prior to the proposal deadline. The goal is to have a healthy mix of experienced, senior panelists, as well as younger panel members at the postdoctoral level. Other important considerations are gender balance and representation of members of the European Space Agency (ESA) and other countries. In Cycle 18, we saw unprecedented proposal pressure, and actually had to add an additional panel after the Phase I deadline. We anticipated a similar level of interest this year, and so retained the additional panel. The final Cycle 19 assessment process involved 132 panelists and TAC members.

Summary of Cycle 19 Results