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4 Enero 2010: University of Notre Dame astronomer Peter Garnavich and a team of collaborators used the NSF’s 4-m Blanco telescope in Cerro Tololo, Chile to discover a distant star that exploded when its center became so hot that matter and anti-matter particle pairs were created. The star, dubbed Y-155, began its life around 200 times the mass of the sun but probably became “pair-unstable” and triggered a runaway thermonuclear reaction that made it visible nearly halfway across the universe.Garnavich and his collaborators discovered the exploding star during the ESSENCE supernova search, a six-year NOAO Survey Program, that identified more than 200 weaker stellar explosions.

18 Diciembre 2009: This special celebratory issue marks the establishment of the National Observatory 50 years ago with the dedication of Kitt Peak National Observatory, providing open access based on peer review to forefront scientific capabilities. It also marks the 100th issue of the NOAO/NSO Newsletter.

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 …

30 Noviembre 2009: Galaxy-scale outflows of gas (“superwinds”) are a ubiquitous phenomenon in both starburst galaxies and those containing an active galactic nucleus but the contribution from dust and molecular gas is largely unknown. (Left) “Pure”, continuum-subtracted, H2 emission on a false-color scale. (Right) Two-color image of the H2 filaments (in red) extending more than 3 kpc above and below the plane of the galaxy (shown in blue).

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 …

3 Noviembre 2009: Image of H2 (red, from NEWFIRM, Kitt Peak National Observatory), and Hα (green, from the Hubble Space Telescope archive) of the Herbig Haro object HH 110. In a study to appear in Nov 10 2009 ApJ, Pat Hartigan and collaborators show how, under the right conditions, collimated supersonic jets in laboratory experiments provide a means to study their astrophysical counterparts.

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 …

12 Octubre 2009: Two NOAO astronomers, Dr. Dara Norman and Dr. Stephen Pompea, at the White House Star Party on Wednesday, Oct 7. The event, attended by local middle school students, was designed to promote science literacy. Telescopes on the White House lawn were focused on Jupiter, the Moon and select stars; interactive dome presentations; and hands-on activities. Dara and Steve had the honor of meeting President Obama and his family, and showing them objects through their telescopes. Dara also shared SPECTRUM, the newsletter of the Committee on the Status of Minorities in Astronomy. Steve demonstrated the Galileoscope, created for the International Year of Astronomy. This new, high-quality telescope kit for students enables kids to learn how to do science, making the same observations that Galileo made 400 years ago.

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 …

23 Septiembre 2009: IC 5067, a star forming region in Cygnus, is also sometimes called the Pelican Nebula. This image was taken May 24, 2009 by Gregor Rothfuss, a first time visitor to the Kitt Peak Advanced Observing Program, with the help of Kitt Peak Visitor Center operator Flynn Haase. They used the VC 20-inch RC telescope with an SBIG STL-6303E camera and AstroDon LRGB filters. Exposures were 120:40:40:40 respectively. This was Mr. Rothfuss’s first experience doing CCD imaging. The Kitt Peak Visitor Center program, which receives no financial support from the observatory, offers paying guests the opportunity to do their own observing and imaging.

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 …

18 Agosto 2009: New funds allocated for ReSTAR by the NSF will provide immediate access to the Palomar 200-inch telescope, fund a copy of the OSMOS optical spectrograph for the Mayall 4-m and more.

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 …

13 Julio 2009: Composite image showing a view of Kitt Peak looking north from near the location of the 0.9-m dome. Left: a re-discovered image from Dr. Aden Meinel taken during his first visit to the summit while scouting potential sites for the National Observatory. Right: image by Dr. John Glaspey from April 2009, shows the changes that have taken place in the last 50 years.

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 …

9 Junio 2009: This issue includes an article by Andrei Tokovinin about speckle interferometry at the SOAR telescope. Short-exposure images of a 1.08" binary star were co-added with re-centering on the global centroid (left), or on the brightest pixel, selecting the sharpest 10 percent of images (right). This latter technique, dubbed “lucky imaging”, is gaining popularity .