Gemini e-Newscast #51

by xzhangIn this release:
Limits on Quaoar’s Atmosphere
2014A Proposal Deadline Imminent
Gemini Planet Imager Progress
GeMS Update
Australian Student Imaging Contest Winner


Limits on Quaoar’s Atmosphere

The Kuiper Belt Object Quaoar, located well beyond the orbit of Pluto, can be studied through occultations as it passes along the line of sight through the crowed plane of the Milky Way. Recent "near-misses" provide some constraints, as Wesley Fraser (National Research Council Herzberg, Canada) and collaborators rule out some pure N2 and CO models. They find that a methane atmosphere is possible, with temperature and pressure values that prevented detectability in the latest observations. The background stars are relatively faint, and rapid photometry is required, so the acquisition camera on Gemini, normally used to adjust the telescope pointing, unusually became the science instrument. Full results from observations on July 13, 2013, at Gemini South are published in The Astrophysical Journal Letters, with more details about the occultation prediction technique in Publications of the Astronomical Society of the Pacific. A Gemini web feature appears here.

Predicted track of Quaoar during an occultation attempt on August 5, 2013.


2014A Proposal Deadline Imminent

The deadline to submit observing proposals for the 2014A semester is nearly here. The date varies by partner, with the earliest being Thursday, September 26 (US) and the latest Wednesday, October 2 (Argentina). Partner-specific information is linked from the Gemini website.


Gemini Planet Imager Progress

Testing is well underway and the team reports that GPI’s computers are operational, software integration is complete, and mechanisms are tested and operational, including the deformable mirrors. All cryogenic systems are functioning and of special note, the Integral Field Spectrograph is under vacuum and cooled to its operational temperature of 70 K.

The instrument is slated for mounting on the flexure rig on September 25, and extremely thorough testing at the Gemini South instrument lab will continue until GPI is mounted on the telescope in late October, with first on-sky observations to begin in November.

Principal Investigator Bruce Macintosh with confirmation of the first successful GPI adaptive optics system test at Gemini South. The display shows the instrument's logo as generated by its deformable mirror and seen by its wavefront sensor.


GeMS Update

The Gemini Multi-Conjugate Adaptive Optics System (GeMS) was off the Gemini South telescope during the Chilean winter, allowing for work to simplify the use during regular operations. Some new tools and interfaces have been developed, and the reliability of several subsystems was improved. An observing run from September 12–16 was the first time the system was on-sky since the improvement work was completed in June and July, and it was challenged with poor weather and some telescope issues. The latest run began last night (September 23), and showed good progress, closing all adaptive optics loops and taking images with the Gemini South Adaptive Optics imager (GSAOI), despite poor natural seeing.

Australian Student Imaging Contest Winner Announced – Image Released, More to Come!

In a special Live from Gemini videoconference event last week, students from St. Margaret's Anglican Girls School in Ascot, Queensland celebrated the release of their school’s image of the galaxy field including IC 5332 (shown). The contest, now in its fifth year, gives Australian students an opportunity to select a target for Gemini to observe and image based on a nation-wide essay contest. This year’s target was suggested by St. Margaret’s student Isobelle Teljega who will be joined by another winner (and image release) to be announced on October 4 (Australian time). The second image is from a variation of this contest for Australian amateur astronomers. Watch Gemini’s Facebook page for updates to this story!