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7 Enero 2010: Gemini Astronomer Percy Gomez presented the work of an international research team (Gemini, Chile and Canada) studying the dynamics of the super group of galaxies Abell 1882. His oral presentation on Wednesday, January 6th was part of the Galaxy Cluster I session at the 215th meeting of the American Astronomical Society. The Abell 1882 super group of galaxies is located at redshift z=0.138, and it is anticipated to eventually form a massive galaxy cluster like Coma. The adjacent figure from this work presents an overlay of the extended X-ray emission originating from at least three distinct groups of galaxies. It also shows the position of the galaxies in the cluster. The team identified over 300 galaxy member candidates (open circles) in the cluster from the SDSS photometric survey and used the Gemini Multi-Object Spectrograph on Gemini South (GMOS-S) to measure new redshifts for over 90 galaxy members. In this way …

7 Enero 2010: Gemini’s Bernadette Rodgers, Inger Jorgensen, Michelle Edwards, and Gelys Trancho shared details about Gemini’s success in gender equality in their poster: “Women Astronomers at Gemini: A Success Story,” which they presented on Tuesday, January 5th at the 215th meeting of the American Astronomical Society. The poster compares the percentage of Gemini Ph.D. scientists to that of the US average between 2006-2008 and finds that Gemini recruited 31% female astronomers compared with only 13.9% for the United States overall. Even more impressive is the gender equity in Gemini’s science management team which is 75% female with a 50% gender balance (currently) in directorate-level positions. The authors also find that the positive gender balance attracts a high level of female applicants for science staff positions and has resulted in significantly higher retention for female vs. male science staff with 88% retention for females compared with 64% for males over the same period. …

5 Enero 2010: Revealing the Explosive Heart of Eta Carinae Astronomers Say Alien Dust Is Nothing To Sneeze At Dynamical Analysis of the Abell 1882 Super Group of Galaxies Women Astronomers Succeed at Gemini Distant Galaxies Grow “Inside-out” and Through Minor Mergers

1 Diciembre 2009: The December 2009 issue of GeminiFocus is now available electronically (downloadable as a PDF). Gemini encourages readers to access the publication electronically as part of Gemini's initiative to find new ways to operate "Greener." GeminiFocus still remains available in a printed version, distributed to Gemini's users through the National Gemini Offices, and is available upon request. This issue features a wide range of science articles that emphasize the variety of observing and instrument modes Gemini provides as well as innovative techniques of our users. In addition to the cover story on adaptive optics imaging of weather on Saturn’s moon Titan, readers will also find: Director’s Message – Exploring Astronomy’s Time Domain Imaging the Most Distant Known Object in the Universe Studying a Z~5 Star-forming Galaxy with NIFS/IFU The Integral Field Spectroscopy User’s Wiki Modeling Nuclear Infrared Emission of Seyfert Galaxies on Parsec Scales Unveiling Remote Globular Clusters in Andromeda The …

6 Noviembre 2009: New results from Gemini observations show the early life of a distant galaxy, building its first generation of stars. An international team led by Mark Swinbank at the Institute for Computational Cosmology at Durham University in the UK and Tracy Webb at McGill University, Canada used the Near-Infrared Integral Field Spectrometer (NIFS) on the Gemini North telescope to make the measurements. See the Durham University press release on this result here. The galaxy's redshift is z=4.92, so the light comes directly from the time when the universe was just over 1 billion years old. While such distant galaxies are normally extremely faint, this one is fortuitously located behind a massive cluster of galaxies, whose gravity acts as a lens to enhance the view. The team finds that the distant galaxy's apparent brightness is increased 12.5 times, and the lensing magnification assists in probing fine spatial detail which would otherwise be …

27 Octubre 2009: Supermassive black holes, with masses millions and billions of times that of the Sun, reside in the centers of most normal galaxies. However, measuring their masses accurately requires precision observations on very small spatial scales, where the gravitational pull of the black hole dominates over the collective effect of the galaxy's stars. An international team led by Davor Krajnović of Oxford University has used the adaptive optics facility ALTAIR with the Near-Infrared Integral Field Spectrograph (NIFS) on the Gemini North Telescope to measure black hole masses in two normal galaxies. These data allow the team to determine the motions of stars in the very centers of the observed galaxies (geminiann09021a). Comparisons with model predictions yield mass estimates of the central black holes of 8 x 108 Msun in NGC 524 and 1 x 107 Msun in NGC 2549. A novel aspect of this work is to use the laser guide …

2 Octubre 2009: The well-known starburst galaxy M82 is a popular target for telescopes of all sizes, and now an international team led by Mark Westmoquette (University College London) have used optical integral field unit (IFU) spectroscopy from the Gemini Multi-object Spectrograph (GMOS) on the Gemini North telescope to help understand the complex dynamics of its galactic wind. The data, combined with wider-field observations by the WIYN telescope’s DensePak IFU, provide a comprehensive view of the ionized gas near the center of M82. As one of the nearest analogues of high-redshift star-forming galaxies, M82 provides a unique laboratory for the study of the relationship between intense star formation and the interstellar medium in which it occurs. M82 hosts a complex network of bright clumps centered around the galaxy’s nucleus (within a diameter of about 500 parsecs; Figure 1). Hundreds of young massive star clusters reside in these knots and drive a kiloparsec-scale superwind …

21 Septiembre 2009: “I thought they were pulling my leg,” said Australian high school student Daniel Tran when he first found out that his entry into the Australian Gemini Partner Office imaging contest was selected as the winner. His target, known as the Glowing Eye Nebula (NGC6751), entered the Gemini South queue for 2009A where it received one hour of telescope time for multi-band imaging with the Gemini Multi-object Spectrograph. The image is shown here as a color composite produced by Travis Rector from Daniel’s data. The contest, sponsored by the Australian Gemini Office solicited high school students from across Australia to submit a target and explain why it would be make a good image. According to Daniel, when he saw the object online at the WorldWide Telescope (WWT, a project of Microsoft) he found that, “its unique colour and structure made me want to know more about it, and the name itself …

16 Septiembre 2009: As part of on-going acceptance testing, FLAMINGOS-2 (Florida Multi-object Infrared Grism Observing Spectrograph) obtained first light images on the Gemini South telescope. Several images from this first observing run are shown here (Figures 1 & 2) and demonstrate the instrument’s initial performance. The telescope and FLAMINGOS-2 together produced high-quality images, as good as 0.4-arcsecond FWHM. The efforts of the University of Florida instrument team, led by Stephen Eikenberry, and a large number of Gemini staff made achievement of this important step possible. The initial tasks completed include basic alignment of the instrument with the telescope and initial checks of the functionality of imaging and longslit spectroscopy modes. A number of significant milestones must be reached before FLAMINGOS-2 will be available for Gemini community scientific use. One severe limitation now is the lack of a science-grade detector. Several more observing runs are planned through the end of the current semester to …

28 Agosto 2009: We found ourselves in the Mataveri airport, the most isolated in the world, in the middle of the Pacific Ocean, 3,700 kilometers from continental Chile and nearly equally distant from Gemini North and Gemini South telescopes. Once again reunited with more than 200 kilograms (approximately 880 pounds) of equipment and education materials that LAN. Cargo graciously transported a few days before our arrival, we began our first astronomical cultural exchange on the island. While our host organizations facility, the Museo Antropológico P. Sebastian Englert (P. Sebastian Englert Anthropology Museum), was being fumigated for dengue fever in the early morning hours, Gemini’s team was assembled. Our team, consisting of La Serena and Gemini Argentina National Gemini Office staff, gathered in the island’s cultural center where we met the inquisitive island students that came to visit us on the first day. That same day the students participated in a talk by Professor …

14 Julio 2009: Star clusters can be thought of as fossils of previous epochs of star formation. Due to this, and their large luminosities, many studies have attempted to use them to peer into the past and reveal how galaxies have formed and evolved. An international team of astronomers, led by Nate Bastian (University of Cambridge) and Gelys Trancho (Gemini Observatory), used the Gemini Multi-object Spectrograph (GMOS) on the Gemini North telescope to observe 16 massive star clusters in the nearest pair of merging galaxies, the Antennae (NGC 4038/39), see geminiann09016a & b. The spectra, (see Figure 3) complemented with deep Hubble Space Telescope (HST) imaging, allowed the determination of the age, mass and velocity of each cluster. The cluster population of the Antennae has been extensively studied in the past, due to the vast quantity of young clusters residing there, but this is the first study of a large sample of clusters …

10 Julio 2009: Using the Altair adaptive optics system with the Gemini Near-Infrared Spectrograph (NIFS) on Gemini North, a US/Australian team have obtained unprecedented high-spatial resolution integral field spectra of the Ultra-Compact H II Region K3-50A. The study reveals never-before-seen morphology and kinematics within this complex region of star formation (see geminiann09015a). The team of Robert Blum (NOAO, Gemini Science Center) and Peter McGregor (Australian National University) observed the 3 arcsecond NIFS field at the core of the region, (covering 0.1 parsec at the object’s estimated distance of 7 kiloparsecs). They found sharp density variations that are thought to result from the action of the high mass central source radiation field and stellar wind on its birth cocoon and immediate surroundings. The observations were made at the Fredrick C. Gillett, Gemini North telescope on Mauna Kea, Hawai‘i in July of 2006. The high angular resolution of the data (~0.2 arcsecond), moderate spectral resolution …

7 Julio 2009: Gemini conducted its first user survey at the end of 2008. Principal Investigators (PIs) for all programs from semesters 2006A – 2007B were asked a series of questions as users of one, or both, Gemini telescopes. There were slightly over 500 unique PIs in the sample and the response rate was just over 50%. The response rate varied by partner country by +/- 5%. This survey represents a significant unbiased sample of Gemini’s user base, and with a response rate of 50%, the results are extremely robust. The respondents greatly favored the queue over classical, but clearly indicated that classical observing should be an option. The respondents were not as positive about Gemini’s instrument suite and the percentage that felt our instrumentation was competitive was disappointingly low. Another area of concern expressed by those who participated was the complexity and ‘unfriendliness’ of the Phase II tool. It was interesting to …

24 Junio 2009: Aimed at deciphering the secrets of archetypal starburst galaxy M82, the Gemini Multi-Object Spectrograph (GMOS) on Gemini North was employed by a team of UK- and US-based astronomers, led by Iraklis Konstantopoulos of University College London (UCL). The astronomers assembled key data for the largest sample of young extragalactic star clusters to date. M82 presents a gas, dust and stellar system that has intrigued scientists for decades due to its irregular, dusty appearance and extravagant super-galactic wind (see geminiann09013a). Konstantopoulos et al. used the Gemini spectra to derive the age of 49 clusters in the disk, nucleus and halo of the galaxy (geminiann09013b). The resulting demographics were used to investigate the starburst history of M82, thus demonstrating the usefulness of star clusters as probes of star formation in environments where stars are too faint to be observed. On this basis, the observations were compared to theoretical models of starburst evolution …

8 Junio 2009: Using the Gemini Near-Infrared Spectrograph (GNIRS), astronomers have obtained an ultra-deep (~29 hour integration) near-infrared spectrum of a massive compact quiescent galaxy at a redshift of about 2.2 (when the universe was only about three billion years old). Understanding how a massive galaxy–especially this early in the history of the universe–can squelch star birth with such efficiency is a challenging problem for both observational and theoretical astrophysicists. The team, led by Mariska Kriek of Princeton University, used GNIRS on Gemini South to dissect the light of the galaxy, identified as 1255-0, in what is the deepest single-slit near infrared spectrum ever taken of a galaxy with a redshift greater than 2 (Figure 1). The spectrum, for the first time, shows absorption line features in this type of galaxy that allow for accurate redshift determination (Figure 2) and is providing insights into this unique category of galaxies that are very massive …

21 Mayo 2009: Set among the beauty of Kyoto University, Japan about 200 users and staff of the Gemini and Subaru observatories and the National Gemini Offices participated in the first joint Gemini and Subaru science conference from May 18-22, 2009. The 5-day meeting provided an opportunity for participants to share a wide range of research topics spanning studies of our solar system and exoplanets to cosmology and the high redshift universe. Users also shared innovative observing techniques, unique collaborations and looked toward the future of both observatories and how they can work together to best serve our users and remain competitive. In particular, methods and procedures for coordinating the use, planning, and construction of future instruments were discussed. The goals of the conference were to promote a mutual understanding of both communities and to highlight the international nature of modern astronomy. These goals were clearly achieved. Key scientific topics of the conference: …

6 Mayo 2009: Winter on Mauna Kea usually consists of fairly short periods of very poor weather (including snowstorms) among longer periods of good conditions brought on by the passages of fronts coming from the northwest. At times a Kona low-pressure system develops causing conditions at Mauna Kea to deteriorate. However, a passing front will usually clear out the low-pressure system and return good astronomical observing conditions on Mauna Kea. This past winter has, to a large extent, lacked fronts that clear out the low-pressure systems. The result has been a large fraction of observing time lost to weather, and very poor conditions when observing was possible. The long-term weather loss for Gemini North for the 18 northern hemisphere “winter” weeks December 24, 2008 through April 28 is about 35%. Figure 1 shows the range and average cumulative weather loss typical for Gemini North for these 18 weeks (orange shaded area of figure). …

14 Abril 2009: An international team led by Ben Burningham (University of Hertfordshire) has discovered a brown dwarf that will likely set the record as the coolest body ever detected outside our solar system. The object, named Wolf 940b, and its central star, a red dwarf named Wolf 940, lies in the constellation Aquarius at a distance of 40 light-years from Earth. Wolf 940b orbits its star at a distance of around 440 astronomical units, more than ten times farther out than Neptune orbits the Sun. At this distance, it takes wolf 940b around 18,000 years to complete a single orbit. The mass of Wolf 940b is probably between 20 and 30 times that of Jupiter. This places it directly in the regime of “brown dwarfs” – objects that are too large to be considered planets but are too small (and cool) to be classified as stars. With a surface temperature of approximately …

6 Abril 2009: A team led by Ph.D. student Luan Ghezzi of the Observatorio Nacional Rio de Janeiro, Brazil, has established that there is no detectable amount of Lithium-6 in five stars that host extrasolar planets. The team used the bench High-Resolution Optical Spectrograph (bHROS) on Gemini South to make the observations. One of the interesting properties of stars known to host giant planets is that these stars are systematically metal-rich (by about ~0.2 dex) relative to field dwarfs not known to harbor giant planets. Two hypotheses have been proposed to account for this excess of elements heavier than hydrogen or helium: primordial enrichment or pollution. The first process indicates that the probability of forming giant planets is a steeply rising function of the intrinsic metallicity of the gas which gave rise to the birth of the star and its planets. The pollution scenario, on the other hand, proposes that during the inward …

30 Marzo 2009: Gemini is pleased to announce the 2009 Gemini Users Meeting that will be held at Kyoto University, Kyoto Japan, in conjunction with the Joint Subaru/Gemini Science Conference. The main goal of the Users Meeting is to provide an opportunity for Gemini's community to provide feedback to the Observatory on both short-term operational issues and long-term strategic issues such as future instrumentation. 2009 Gemini Users Meeting Agenda 9:30 Welcome (Packham) I Operations Status and Reports - Chair: TBD 9:35- Queue completion rates and Operational Efficiency (Jørgensen - 30+5) 10:10 - Dataflow Project (Labrie - 15+5) 10:30 - Gemini Publications: Productivity and Impact (Crabtree - 15+5) 10:50 -Break (20) II Instrumentation / Adaptive Optics Updates - Chair: TBD 11:10 - Altair/LGS (Christou - 10+5) 11:25 - MCAO (Rigaut - (15+5) 11:45 - NICI (TBD - 10+5) 12:00 - GNIRS (Geballe - 10+5) 12:15 - FLAMINGOS-2 (Gomez - 15+5) 12:35-GMOS CCDs (TBD - …