Hubble Cycle 18 Proposal Selection

Claus Leitherer,, & Daniel Apai,


When the Cycle 18 Call for Proposals was released on December 9, 2009, Cycle 17 was well underway, and the newly installed—as well as the prior-generation—instruments on Hubble had been calibrated and characterized after Servicing Mission 4. Unlike the situation during the previous Call for Proposals, astronomers could prepare their proposals and estimate resources knowing the instruments were in place and had already been checked out. 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 18. The Near Infrared Camera and Multi-Object Spectrometer (NICMOS) was available for proposers as well. However, when the Call for Proposals was issued, the NICMOS cooling system had not yet been restarted, and NICMOS was inactive. The decision on when the cooling system would be restarted had not yet been made. Nevertheless, the proposers were advised to assume NICMOS would be available during Cycle 18.

The Phase I deadline for Cycle 18 was February 26, 2010. While some proposals were received well in advance of the deadline, most proposals arrived on the very last day, with an ever-increasing number piling up during the final minutes before 8 p.m. Eastern time. As many astronomers living on the East Coast may remember, that particular day was one of many when snowstorms hit the area and caused a snow emergency. The Institute was actually operating under liberal leave on February 26. Luckily, with the help of our dedicated staff, the proposal submission process was completed without major hiccups. In the end, we received 1,051 proposals. The final tally was not known until a few days after the deadline because of duplicate submissions and some withdrawals.