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12 Octubre 2011: The staff of the Gemini Observatory wish to congratulate the winners of the 2011 Nobel Prize for Physics: Saul Perlmutter (Lawrence Berkeley National Laboratory and University of California, Berkeley), Brian P. Schmidt (Australian National University), and Adam G. Riess (Johns Hopkins University and Space Telescope Science Institute, Baltimore). The Nobel prize citation recognizes two teams for the discovery of the accelerating expansion of the universe based on observations of supernovae (SN). Since the original discoveries, both teams have used Gemini data to pursue their studies, especially as part of the Supernova Legacy Survey (SNLS) and the ESSENCE survey. The origin of the acceleration is also known as dark energy, and its further study requires the power of the world's largest and most sensitive telescopes to characterize distant supernovae in the early universe. Once characterized, these exploding stars can be used as "standard candles"—objects of known intrinsic brightness—to measure the expansion …

29 Septiembre 2011: New observations with the Gemini Multi-Object Spectrograph on Gemini North confirm a new dwarf companion to the Andromeda Galaxy. The Local Group of galaxies includes many smaller dwarf galaxies in addition to the large Milky Way and Andromeda spiral galaxies. These dwarfs tend to contain a high proportion of dark matter, and theories of galaxy formation and dark matter make specific predictions about their presence and quantity. The Local Group contains many fewer dwarf galaxies than “standard” models of galaxy formation in a dark matter-dominated universe predict and at least two outstanding questions remain: 1) whether astronomers have missed some of the dwarfs (which, even though these in the Local Group are relatively close, are hard to see because they are intrinsically faint), or 2) whether dark matter theories need to be revised. Now, adding new evidence to the debate, Eric Bell (University of Michigan) and collaborators report the discovery …

29 Septiembre 2011: Left: This close-up image of the nearby galaxy M101 was obtained with the Mayall 4-meter telescope at Kitt Peak National Observatory. SN2011fe, the closest Type 1a supernova to be observed since 1972, is visible as the bright, bluish star in the lower, right portion of the image (mouse over the image to highlight). This image was obtained on September 18, 2011, about two weeks after supernova PTF11kly achieved its peak brightness. Right: WIYN/WHIRC light curve, showing relative magnitudes in the J, H and Ks bands. Initial observation taken on August 26, 2011.

31 Agosto 2011: The September 2011 NOAO Newsletter is online and ready to download. This issue includes information pertaining to the 2012A Call for Proposals, which are due September 30th. On the Cover This image illustrates the dome floor of the Blanco 4-m telescope with components of the f/8 handling system in the early stages of its installation for use with DECam. Other completed work includes the DECam focal-plan, which now has all 74 science-grade CCDs installed.

22 Agosto 2011: An international team of astronomers, using data from the Gemini North telescope, are revealing the history of the outer Solar System by measuring the mutual orbits of extremely widely separated binaries located beyond Neptune in the icy Kuiper Belt. The researchers conclude that these “trans-Neptunian binaries” formed close to their current locations, and—contrary to previous suggestions—that they may have formed from direct collapse in the disk of material that produced the planets and other solid bodies of the Solar System. Binary systems are found in most minor planet populations, such as asteroids, but binaries in the Kuiper Belt are notable due to the frequency of very widely-separated systems and those with nearly equal-sized primary and secondary bodies. A team of researchers led by Alex Parker (Harvard-Smithsonian Center for Astrophysics; formerly of the University of Victoria, Canada) followed some of the most widely-separated Kuiper Belt binaries known, using a combination of …

8 Agosto 2011: Thanks to a partnership between Gemini South and the Extension Department of the University of La Serena as well as participation by the Municipality of La Serena and the Tourism Board (SERNATUR), the Viaje al Universo and AstroDay Chile programs introduced our Chilean host communities to Gemini (and astronomy) in exciting new ways. Already, anticipation is building for the 2012 programs. Kicking off the week’s events, about 3000 kids, parents and public gathered for AstroDay Chile, which is one of the most significant public outreach astronomy programs in Chile. The AstroDay Chile program offered a variety of experiences thoughtout the day on Saturday, July 16th at the Extension Center of the University of La Serena (ULS). "It is very pleasing and impressive to see how each year there are more families coming to this event, even from other cities. I received very flattering comments and for us as a university …

8 Agosto 2011: Another supernova has exploded in the Whirlpool Galaxy (M51), and now astronomers have identified its unusual progenitor using data from Gemini. Several amateur astronomers independently discovered the bright supernova, designated SN 2011dh, early in June 2011. The object was quickly classified as a Type IIb supernova based on its spectrum; this class of supernovae likely arises from massive stars that have lost some, but not all, of their outermost layers of hydrogen. Within hours of the discovery of SN 2011dh a multi-national science team, including Morgan Fraser (Queens University Belfast, UK) triggered their Gemini Target of Opportunity (ToO) program to obtain high-resolution images with the near-infrared camera NIRI at the Gemini North telescope in Hawai‘i. However, snow and poor weather on Mauna Kea (where Gemini North is located) kept the telescope closed for a few nights, delaying the observations. When observations were again possible, NIRI was successfully used with the …

19 Julio 2011: The Milky Way’s near neighbor, the Large Magellanic Cloud (LMC), has accreted a smattering of stars from its smaller neighbor, the Small Magellanic Cloud (SMC). This image shows the LMC imaged by the Spitzer Space Telescope. Overlaid in red and blue, with the colors representing their line-of-sight velocities, are the stars whose origin has been traced to the SMC. These stars were discovered by a team led by NOAO astronomer Knut Olsen, through analysis of spectra obtained at the CTIO 4-m Blanco telescope.

17 Junio 2011: In early April 2011, after more than a decade of effort, the Gemini Multi-Conjugate Adaptive Optics System (GeMS) saw starlight for the first time. With this milestone GeMS kicked off a new era in adaptive optics (AO) technologies both for Gemini and for future generations of even larger telescopes that will require advanced AO to make them scientifically viable. These first GeMS photons, captured on April 19, 2011 (see Figure 1), kept hopes high for equally successful progress when commissioning resumes in late 2011 and then for system verification in early 2012. Adaptive Optics is a well-known technology that compensates for image distortions induced by atmospheric turbulence. The vast majority of large telescopes in the world are now equipped with AO systems of various kinds, and many use lasers to create artificial stars (laser guide stars, LGS) in order to probe and correct for atmospheric turbulence over a larger portion …

16 Junio 2011: An international team of astronomers using the Gemini North telescope revealed that a powerful outburst of radiation originated from a massive black hole at the center of a distant galaxy. The black hole, thought to be about a million times more massive than our Sun, appears to have ripped apart a star that orbited too close and in the process released a powerful beam of energy. The light emitted by the beam crossed 3.8 billion light years of space to be eventually detected by NASA’s Swift satellite. This triggered a flurry of activity by an international team of astronomers who rushed to make detailed observations of this remarkable event with Gemini and other telescopes. Their research is published today in two companion papers in the June 16, 2011 issue of the journal Science. “The high energy X-rays and gamma-rays detected by Swift persisted at an extremely bright level for weeks …

14 Junio 2011: The chance alignment of a pair of helium white dwarfs – both originally about the mass of the Sun – is showing how binary stars interact and eventually suffer a long slow demise. The pair, known as CSS 41177, are held in a close gravitational embrace and aligned such that they eclipse each other as seen from the Earth. This serendipitous circumstance allows astronomers to explore the history of these stars, and their conclusions offer a laboratory to test models of stellar evolution and the extreme states of matter that white dwarfs exhibit. The members of the binary pair, only the second of its kind known, have both endured extreme mass loss as a result of their close pairing. A white dwarf is the usual endpoint of stars like the Sun, but to end as a helium white dwarf, it must lose most of its outer hydrogen mass to reveal …

2 Junio 2011: NGC3628, an edge-on spiral about 35 million light years distant, the Crescent nebula (NGC6888, a shell of gas excited by HD192163, a Wolf-Rayet star) and M82, a peculiar galaxy at a distance of about 12 million light years. These images were taken through B, V and hydrogen alpha filters at the WIYN 0.9m in April 2011 as part of a special Visitor Center AOP program. A few nights on the 0.9m unexpectedly became available, and Glen & Joan Saurdiff responded to this opportunity to acquire images with a research telescope using the S2KB camera. The image processing was done by Flynn Haase of the Visitor Center, telescope operation by Steve Peterson and Katy Garmany.

20 Abril 2011: The Kepler Cluster Study (PI: Søren Meibom, Harvard-Smithsonian CfA) is a program to search for planets around members of 4 open star clusters in the field of view of NASA’s Kepler mission, and to study the relationships between stellar rotation, age and mass. “Ground-based observations in young (~< 600 million years) open clusters, using NOAO facilities (WIYN 3.5m, the WIYN 0.9m, the CTIO Blanco 4m, and CTIO 1m), have suggested to us that a well-defined relationship exist between the rotation periods, ages, and colors of late-type stars”, says Meibom, “and that observations of such stars in older clusters can define a surface in the 3-dimensional space of rotation, color (mass), and age (figure 1, left). Now, using Kepler, Meibom and his colleagues have extended this surface to 1 billion years by measuring the relation between rotation and color for members of the open cluster NGC6811 (figure 2, right).

13 Abril 2011: Brown dwarfs bridge the astronomical gap between stars (like the Sun) and planets (like Jupiter). Only during the last few years have enough cool brown dwarfs been discovered to begin to test the physical models that describe their atmospheric physics. Still, the population remains sufficiently small making the discovery of additional examples significant. Ben Burningham (University of Hertfordshire, UK) and collaborators report the discovery of one late-type brown dwarf in the Monthly Notices of the Royal Astronomical Society. The team initially selected candidates based on their infrared colors in the UKIRT Infrared Deep Sky Survey Galactic Plane Survey. Spectroscopy obtained with the Gemini Near-Infrared Spectrograph (GNIRS) on the Gemini North telescope combined with photometry from the Spitzer Space Telescope enable the secure identification of its spectral type as T8.5. The authors conclude that the temperature of this object, UGPS J0521+3640, is between 600 to 650K, and it has a mass …

15 Marzo 2011: Seven years ago, Gemini Observatory began a modest program in our local Big Island community called Journey Through the Universe (JTtU). At that time the program was administered (Nationally) by the National Center for Earth and Space Education and Gemini began a journey, the magnitude of which nobody could have anticipated back then. Today, JTtU on the Big Island has grown almost beyond recognition from those early days. In its 2011 incarnation, which occurred from February 10-18, a diverse and impressive number of participants joined in the excitement. To summarize the program’s impact, over 6,500 students joined over 50 scientists, engineers and educators from local (and national) observatories and educational organizations. 310 classes participated with the help of 31 “Ambassadors” who escorted visiting educators who, for many, hadn’t seen a K-12 classroom since they were there as students themselves! The unique partnership between Gemini, other local observatories, the Hawai‘i state …

9 Marzo 2011: It is with profound sadness and also deep sense of respect that I write this note to recognize the contributions of Victor to CTIO and, more broadly, to the generations of astronomers that have passed through CTIO, both as staff and as users of the facilities. I had the honor of overlapping with Victor briefly when I arrived at CTIO as a postdoc, but didn't get to know him well then. However, through interactions with the many people whose lives he touched, including astronomers, engineers, administrative and facilities staff, I've grown to understand the depth of his impact on CTIO and the “Tololino culture”. His leadership set CTIO on a solid course as a world-leading facility, both in its technical achievements and its culture of close teamwork and pride in the work that is done. That leadership was combined with a father-like quality for the staff, which firmly established the …

4 Marzo 2011: The March 2001 NOAO Newsletter is online and ready to download. About the cover image: Against a background of Eta Carina, taken with the SOAR Adaptive Module in Natural Guide Star mode (clockwise from top left): The SOAR telescope on Cerro Pachón, the SOAR Adaptive Module (SAM), the Spartan Infrared Camera, and the Goodman High Throughput Spectrograph.

10 Febrero 2011: It’s summertime in the southern hemisphere, and for the past four years this has become synonymous with a community outreach program known to Gemini staff and family as AstroDay Chile. This program, which started as a mere handful of booths and kiosks from AURA observatories in 2005, has grown to host more than 17 institutions from Chile and beyond. AstroDay Chile, continues to be a leading community outreach program for scientific and public observatories the country. However, this year (2011) a new element called Viaje al Universo Chile (Journey Through the Universe) has been adapted and added to the program. “We are always trying to improve and modify our programs in order to partner with new entities such as local universities and city halls, as well as giving the opportunity for more people to play a role in our highly visible events,” says Ma. Antonieta Garcia, who organizes the local …

26 Enero 2011: On July 19, 2009 Australian amateur astronomer Anthony Wesley spied a dark scar in the clouds of Jupiter. Wesley alerted professional astronomers and immediately both Gemini telescopes and other large telescopes around the world (and in space) trained their instruments on Jupiter’s new transient feature. Now, after more than a year of studying the unique data a team led by Glenn Orton of NASA’s Jet Propulsion Laboratory and Leigh Fletcher of Oxford University have confirmed that this collision was not like at least one similar past event. The results, published in a recent issue of the journal Icarus (see citations at the end of this feature), indicate that the colliding body was rocky and not an icy comet like the last known collision with Jupiter, the comet Shoemaker-Levy 9 in 1994. These results confirm earlier indications from Hubble Space Telescope data that the collision involved a dense rocky object rather …

25 Enero 2011: Life is busy at the Blanco 4-m telescope at Cerro Tololo Inter-American Observatory right now. This is a bird’s eye view of the dome floor during the early stages of the installation of the f/8 handler for use with the Dark Energy Camera, DECam.