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Issue 63, October 2016

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Issue 63, October 2016 1 Director’s Message Markus Kissler-Patig 3 A Gemini Spectrum of a World Colder than a Night on Maunakea Andy Skemer 7 Science Highlights Nancy A. Levenson and Mischa Schirmer 10 News for Users Gemini staff contributions 14 On the Horizon Gemini staff contributions 18 Observatory Careers: New Resources for Students, Teachers, and Parents Gemini staff contribution ON THE COVER: GeminiFocus October 2016 Close-up view of dark GeminiFocus is a quarterly publication galaxy Dragonfly 44 of the Gemini Observatory using GMOS-North. A 670 N. A‘ohoku Place, Hilo, wide-field view appears Hawai‘i 96720, USA in the box at upper Phone: (808) 974-2500 Fax: (808) 974-2589 right. Learn more about this image in Science Online viewing address: Highlights starting on www.gemini.edu/geminifocus page 7 in this issue. Managing Editor: Peter Michaud Credit: P. van Dokkum Science Editor: Nancy A. Levenson et al., Gemini Associate Editor: Stephen James O’Meara Observatory/AURA Designer: Eve Furchgott/ Blue Heron Multimedia Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation or the Gemini Partnership. ii GeminiFocus October 2016 Markus Kissler-Patig Director’s Message Strategic Vision for 2020+ Nears Completion Gemini is finalizing the Observatory’s broad strategic vision for the years beyond 2020. As reported in the last two issues of GeminiFocus, the Gemini Board has set up a Strategic Vi- sion Committee (find their terms atthis link), and requested your input through a survey focusing on the way forward and which opportunities we should pursue. Thank you for sending us around 250 responses, together with many useful comments and suggestions. While the committee is now analyzing the responses, at first glance we received broad sup- port for the general principles set forth by the Gemini Board of Directors and its Science and Technology Advisory Committee. Many of the various specialization scenarios were also supported, although generally at levels of 20-30% of the total observing time. The most popular scenario was the status quo! We welcome this as a sign of confidence in the way Gemini is currently operating — so thank you! We will nevertheless not stop innovating to support your scientific endeavors and will continue to strive to be the best observatory in the world for the execution of flexible, innovative, and efficient science programs. The final version of the Gemini Board’s Strategic Vision is expected after their next meeting in November. Keeping in Touch With You Gemini continues its involvement in activities relevant to our participating countries. For instance, Gemini leadership attended both the 13th Annual Meeting of the Chilean Astro- nomical Society (SOCHIAS) in Antofagasta, Chile, and the Canadian Astronomical Society (CASCA) meeting in Manitoba, Canada. In August and September, Gemini also participated in the Sociedade Astronômica Brasileira (SAB) meeting in Ribeirão Preto, as well as the Aso- ciación Argentina de Astronomía (AAA) meeting in San Juan. Attending these gatherings gives us an opportunity to present the latest news and developments from Gemini and, per- October 2016 GeminiFocus 1 haps more importantly, to obtain feedback that other groups are contributing! Current- directly from a broad community of users ly we offer four of these in the regular Call throughout Gemini’s participating countries. for Proposals. As an annual event, we also hit the road touring North America to visit various as- Other Exciting News tronomy departments at several universities Among the less visible but important news, and share information while learning more AURA is extending the limited-term partner- about their interests. This year, Heidi Hammel ship agreements with Korea and Australia. (Executive Vice President of the Association The Korean Astronomy and Space Science of Universities for Research in Astronomy; Institute (KASI) is the contact for Korean as- AURA) and I visited six campuses in five days. tronomers, and is expanding its agreement These included the University of Maryland, to use Gemini into the years 2017 and 2018; Penn State, University of Texas Austin, Texas and Astronomy Australia Limited (AAL) has A&M, and the University of California (both renewed its yearly agreement for 2017, to Berkeley and Santa Cruz). We thoroughly en- continue providing the Australian commu- joyed our visits and learned a lot about these nity with access to Gemini. thriving departments and their interests and wishes for Gemini. It also gave us the op- As usual, do not miss our latest scientific re- portunity to present some of AURA’s other sults in this edition of GeminiFocus, some of activities and point our users to some of the which made the front page of national news. new opportunities at Gemini. (For example, Whether it is exploring frozen exoplanets, or have you tried the Fast Turnaround mode to characterizing dark matter galaxies, we are submit proposals? Or considered a visitor in- proud to see a wide variety of trail-blazing strument to bring?) If you would like us to results continuously streaming out of Gemi- tour your institution next year, please feel ni; we are true to our purpose: Exploring the free to drop me a note. Universe, Sharing its Wonders! Visitor Instruments and Markus Kissler-Patig is the Gemini Observatory Other Support Director. He can be reached at: The feedback we’ve received from our out- [email protected] reach efforts have been exceedingly fruitful. The community especially supports our vi- sion for continuing to complement Gemini observing with visitor instruments. Many groups in our community have already seized the opportunity and brought, or are planning to bring, instruments to Gemini; the list of interested parties is growing, with over 10 visitor instruments already in the queue for the next 3-5 years. We can handle a few more, so feel free to consider this pos- sibility (for more details, see this website). If you don’t have an instrument to offer up, simply consider using visitor instruments 2 GeminiFocus October 2016 Andy Skemer A Gemini Spectrum of a World Colder than a Night on Maunakea Gemini North’s unique spectroscopic capabilities at 5 microns combined with queue scheduling delivered challenging deep spectra of a nearby, very cool brown dwarf. The results provide a strong analog of a Jupiter-mass planet and the coolest known compact object outside of our Solar System. For more than 50 years, scientists have observed our Solar System’s gas giant planets in the infrared. At these wavelengths, it is possible to measure their intrinsic luminosities, chemical abundances, and thermal profiles. We now live in an age where thousands of planets have been discovered orbiting other stars. For a handful of these worlds, we are beginning to study their individual properties in a way that emulates Solar System studies from 50 years ago. Figure 1. Left: VLT image of Jupiter at 5 microns (image by Leigh Fletcher). Right: Gemini spectrum of WISE 0855 at 5 microns (the faint white vertical line). October 2016 GeminiFocus 3 parsecs from the Sun; together with its photometry, this implies an ef- fective temperature of ~ 250 K (the coldest known compact object out- side of our Solar System) and a mass of 3-10 MJupiter. When WISE 0855 was discovered, a flurry of interest in characterizing its atmosphere ensued. Models predict that at 250 K, WISE 0855 should have a spectrum dominated by water va- por, phosphine, and perhaps a sub- tle influence from water clouds. But the method typically used to study brown dwarf atmospheres — near- infrared spectroscopy (1-2 microns) — is infeasible on current facilities due to WISE 0855’s intrinsic faintness (J = ~ 25 magnitudes). Counterin- Figure 2. The difficulty of studying exoplanets is that tuitively, the best way to obtain a spectrum GNIRS spectrum of they are much fainter than their host stars. of WISE 0855 is with ground-based M-band the 250 K brown Dedicated instruments, such as the Gemini (5 micron) spectroscopy, which, due to the dwarf, WISE 0855. Planet Imager, can detect the light of warm sky background brightness, is usually far less WISE 0855 is our Jupiter-mass analogs. However, the capabil- sensitive than other wavelengths. As WISE first opportunity to ity does not yet exist to image a planet as study an extrasolar 0855 has an M-band magnitude (measured planetary-mass cold as Jupiter around another star. from WISE) of 13.9, it is easier to detect at object that is nearly M-band than J-band. There are currently no An alternative approach is to study free- as cold as our own space-based 5-micron spectrographs. gas giant planets. floating planets and brown dwarfs. These objects slowly cool as they radiate away the energy from their gravitational collapse, with Enter Gemini no core fusion to create new energy. Brown The previous faintest spectrum ever taken dwarfs can be found over a much wider tem- from the ground at M-band was a Gemini perature range than exoplanets. And tem- Near-Infrared Spectrograph (GNIRS) spec- perature, rather than mass, dominates the trum of Gliese 570 D which is 1.6 magni- appearances of self-luminous planets and tudes brighter than WISE 0855. Scaling from brown dwarfs. previous observations, a low-resolution, By far the best extrasolar analog to Jupiter low signal-to-noise GNIRS spectrum of WISE is the brown dwarf WISE 0855. Kevin Luh- 0855 was just barely possible in a 14-hour man of Pennsylvannia State University dis- integration (29 hours including overheads). covered this free-floating object in 2014 But there are always practical considerations while searching Wide-field Infrared Survey when working at an instrument’s limits.
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