Gemini e-Newscast #33 -- September 2, 2011

by xzhang

1. Trans-Neptunian Binaries and the History of the Outer Solar System

Alex Parker (Harvard-Smithsonian Center for Astrophysics; formerly of the University of Victoria, Canada) and collaborators have studied the mutual orbits of extremely widely separated binaries in the Kuiper Belt. They conclude that these "trans-Neptunian binaries" formed close to their current locations, and (contrary to previous suggestions) that they may have formed from direct collapse. The team took advantage of short observations during excellent seeing conditions to measure relative astrometry at the 0.02 arcsecond level using GMOS on Gemini North, along with other observations. The complete paper will be published in the Astrophysical Journal. A preprint is posted at astro-ph, and some more information is available here.

2. Phase I and II User Tool Improvements

Gemini has begun a significant software development effort to improve the usability of the Phase I Tool (PIT) and the Observing Tool (OT). Features under development for the 2012A OT (to be released in December 2011) include automatic GCAL configurations and automatic guide star selection. A major re-write of the PIT is also underway. The primary goal of this work is to improve the creation of the initial Phase II observations, and significant user interface changes are also planned. Automatic guide star searches will be added and most text sections will be edited using LaTeX or Word templates. Please contact Bryan Miller if you have questions or comments on this project.

3. GMOS-North Upgrades

Gemini has purchased red-sensitive CCDs manufactured by Hamamatsu Photonics for GMOS-N. We have encountered several difficulties working with these devices and the upgraded ARC controller, so their installation in GMOS is delayed. As an interim solution, we intend to install e2v deep depletion CCDs, in order to provide an improved GMOS-N focal plane for the community as soon as possible. See the GMOS status and availability page for updated general information. More details about the Hamamatsu and e2V detectors are also posted on the Gemini website.

The Gemini e-Newscast is sent periodically to Gemini users. To leave this list at any time, send email to with a subject of "unsubscribe Gemini-eNewscast" (without the quotation marks). To subscribe to the list, send a message to with a subject of "subscribe Gemini-eNewscast" (without the quotation marks).  An archive of recent past announcements is available.