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11 Marzo 2010: Galaxies are the building blocks of the universe, so accounting for their formation is an essential problem in astronomy. Most galaxies are either spiral or elliptical, with the latter tending to be larger and more massive. One suggestion that is grounded in fundamental measurements of the universe as a whole is that merging spiral galaxies form elliptical galaxies. A way to test the predictions of this merger hypothesis is to observe examples of galaxy merging in process. Barry Rothberg and Jacqueline Fischer of the Naval Research Laboratory (US) have done that, drawing important conclusions about the objects they observed and the techniques astronomers use to measure them. One critical property of a galaxy is its mass. The motion of stars is sensitive to the gravitational effect of the mass, so measuring the stellar motion can yield a galaxy's mass. Observations of characteristic features in the spectra of stars are sensitive …

11 Marzo 2010: Consequences of galaxy-scale outflows are profound in the early universe, and an international team led by David Alexander at Durham University (UK) provides insight into the process using new observations with the Gemini Near-Infrared Integral Field Spectrometer (NIFS) on Gemini North. The material between galaxies is observed to be enriched in metals (elements more complex than helium) compared with primordial abundances, which requires early generations of star formation to produce the metals. The galactic outflows thought to be responsible for this enrichment must be extremely energetic for the material to escape a galaxy’s strong gravitational pull. Moreover, outflows and superwinds may provide some of the feedback that suppresses further star formation, thus accounting for the sharp decline in the cosmic star-formation rate from its peak at redshifts between z ≈ 2 to 3. Either the stars themselves (through winds and supernovae) or winds and jets that are a result of …

10 Marzo 2010: Our national astronomy observatory was dedicated on Kitt Peak 50 years ago in March 1960. In celebration of the 50th anniversary, Kitt Peak National Observatory’s first Director Dr. Aden B. Meinel will speak about the history of the national observatory and Bernard Siquieros, Education Curator of the Tohono O’odham Nation’s Cultural Center and Museum, will share a Tohono O’odham perspective on the meaning and history of Iolkam Du’ag, or Kitt Peak, and the Baboquivari Range. The program entitled “Why Kitt Peak?” will be presented at the Steward Observatory, 933 North Cherry Avenue, Room N210, at 7:30 pm on Monday, March 22nd; it is free of charge and open to the public. Following the talks, the telescope in the Steward Observatory dome will be open for public viewing of the night sky (weather permitting). The site for the proposed national observatory was constrained by practical considerations that limited the choice to …

1 Marzo 2010: In celebration of the 50th anniversary of our national astronomy observatory, Dr. Alan Dressler will present “The Living History of the Universe” at the Marriott University Park, 880 E 2nd Street, on March 17 at 7:30 pm. This special program is available to the public at no cost. Every minute of every day, light from the remote past arrives at Earth, much of it originating before the Earth itself was born. Astronomers look at the history of the Universe as it actually happened, by gathering the light from faint, distant galaxies that are frozen as slices in time. Drawing connections between what we see in the young, distant Universe to the one of our own time is challenging, however. A small history of this difficult endeavor, recounted by one of its key players, reveals how science works and the persistence of human curiosity. Alan Dressler is an astronomer at the …

28 Febrero 2010: The staff of Gemini Observatory extends its deepest sympathies to the families of those who suffered losses or are displaced due to the major magnitude 8.8 earthquake that struck southern Chile early Saturday morning, February 27, 2010. Gemini was fortunate that there were no significant structural damages to any of our facilities. The earthquake disrupted observations on early Saturday morning for less than 30 minutes. Subsequent operations have been essentially normal with the exception of Internet connectivity. We are dealing with communications and minor power inconsistencies that should be solved once general Chilean infrastructure issues are resolved. The temblor struck about 700 kilometers south of Gemini South which is on Cerro Pachón. Both of the Gemini telescopes are located in seismically active locations and on October 15, 2006 Gemini North experienced a major (magnitude 6.7) earthquake that inflicted significant damage to the telescope and related systems. In total 26 nights …

25 Febrero 2010: With Issue 101 we will begin producing only two issues a year, in March and September. Additionally, we are changing the section organization to make the Newsletter more useful and informative to our readers.

15 Febrero 2010: The groundbreaking for the viewpoint Vista Sidney Wolff took place on February 1, 2010 on the road to the Cerro Tololo Inter-American Observatory (CTIO) in Chile. The site features a beautiful view of the SOAR and Gemini telescopes and also of the site selected for the Large Synoptic Survey Telescope (LSST). The construction of the vista point is a tribute to Dr. Sidney C. Wolff's leadership in enabling the construction of these world-class facilities on Cerro Pachon high in the Andes mountains. Dr. Wolff served as President of the SOAR Board and first Director of the Gemini Observatory.

26 Enero 2010: It has been assumed for some time that binary supermassive black holes (SMBH) should be common in the universe, given that galaxies regularly interact and merge and that most, if not all, galaxies contain a SMBH. Such a SMBH will only be detected as a quasar when it is accreting matter. And galaxy merging is a leading proposal to trigger such accretion. Now the first luminous, spatially resolved binary quasar that clearly inhabits an interacting/merging galaxy pair has been reported. ( SDSS J1254+0846: A Binary Quasar Caught in the Act of Merging, Green et. al., Ap. J accepted Jan. 2010 ). The unique properties of this system allow detailed numerical simulations to create plausible scenarios for the histories of both the host galaxies and the SMBH that inhabit them. The first spectrum confirming this binary QSO was taken by A. Myers at the KPNO Mayall 4-meter using R-C Spectrograph on …

15 Enero 2010: Two symposia will take place in Tucson during the month of March, 2010. From First Light to Newborn Stars happens from March 14-17, followed by The Eventful Universe March 17-20. On March 17th both symposia will meet together for talks by our distinguished invited speakers (including Vera Rubin, Nick Suntzeff, Heather Morrison, Charlie Lada, and Alan Dressler) to celebrate the 50th anniversary of the National Observatory. Please go to the link above to register for either symposium.

11 Enero 2010: Looking into the distant universe, astronomers look into the past. Observations of distant galaxies directly reveal those galaxies as they once were. They also indicate indirectly the stages of development that result in the nearby galaxies that are typical of our own Milky Way and other older galaxies today. Christopher Conselice (University of Nottingham, UK) and collaborators used the Near Infrared Imager (NIRI) with the adaptive optics system Altair and laser guide stars on the Gemini North telescope to investigate galaxies at redshifts from z =1 to 2 (when the universe was only 25 to 40% of its current age). They show that the massive galaxies of their sample tended to be extremely compact. These instruments afford high angular resolution, which is essential to measure fine spatial scales in the distant galaxies. In a sense, the galaxies grow "inside-out," adding mass to the outer regions beyond an initial dense core. …

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. …

6 Enero 2010: Most searches for planets around other stars, also known as exoplanets, focus on Sun-like stars. Those searches have proven successful, turning up more than 400 alien worlds. However, Sun-like stars aren’t the only potential homes for planets. New research by astronomers at the Harvard-Smithsonian Center for Astrophysics (CfA) and the National Optical Astronomy Observatory (NOAO) confirms that planet formation is a natural by-product of star formation, even around stars much heftier than the Sun.

6 Enero 2010: Although the International Year of Astronomy 2009 (IYA2009) comes to a formal close this weekend with a ceremony in Padua, Italy, numerous core programs conducted during the year will carry on in 2010 and beyond, many led by educators and outreach professionals in the United States, including NOAO’s Dr. Stephen Pompea (Galileoscope) and Dr. Connie Walker (Dark Skies Awareness).

6 Enero 2010: Hundreds of thousands of school children around the country will be a ble to explore the Moon, planets, and our galaxy thanks to a $250,000 donation by Ric and Jean Edelman. The Edelmans, founders of Edelman Financial Services, one of the country’s leading independent financial advisory firms, have donated $250,000 to the American Astronomical Society to fund the acquisition and distribution of more than 15,000 Galileoscopes to schoolteachers nationwide and train them on adding the telescope kits to their curriculum. The program is operated in partnership with the National Optical Astronomy Observatory.

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

5 Enero 2010: For almost two centuries, humans have looked up at a bright star called Epsilon Aurigae and watched with their own eyes as it seemed to disappear into the night sky, slowly fading before coming back to life again. Today, as another dimming of the system is underway, mysteries about the star persist. Though astronomers know that Epsilon Aurigae is eclipsed by a dark companion object every 27 years, the nature of both the star and object has remained unclear.Now, new observations from NASA’s Spitzer Space Telescope — in combination with archived ultraviolet, visible and other infrared data — point to one of two competing theories, and a likely solution to this age-old puzzle. One theory holds that the bright star is a massive supergiant, periodically eclipsed by two tight-knit stars inside a swirling, dusty disk. The second theory holds that the bright star is in fact a dying star with …

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 …