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18 Mayo 2009: The Orion Nebula seen with the infrared eyes of the WIYN High Resolution Infrared Camera (WHIRC) in the emission lines of HeI (1083 nm; blue), FeII (1644 nm; green), and H2 (2122 nm; red).

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). …

21 Abril 2009: This Mayall 4-m image of the Medusa Nebula was released during the "Around the World in 80 Telescopes" webcast held from April 3-4, 2009.

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 …

6 Abril 2009: This Blanco 4-m image of NGC 6520, and nearby dustcloud Barnard 86, was released during the "Around the World in 80 Telescopes" webcast held from April 3-4, 2009.

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 - …

17 Marzo 2009: In a paper published in the March 19, 2009 issue of Science Express, Justyn Maund and Stephen Smartt present data from the Gemini Observatory and Hubble Space Telescope (HST) that confirms the disappearance of the progenitors of two Type II supernovae (SNe). The only other supernova progenitor of this sort known to have definitively disappeared was SN 1987A in the Large Magellanic Cloud, part of our Local Group of Galaxies. Because the identity of the stars found in pre-explosion images has now been confirmed, this work provides the important “nail in the coffin” that the now missing Red Supergiants were the progenitors. The two supernovae, denoted 1993J and 2003gd, both had confirmed pre-existing progenitors identified from archival data which allowed the researchers to compare pre-supernova identification of the progenitor star with post-supernova observations. Maund and Smartt used a technique where images were taken after SN 2003gd had faded away, and …

13 Marzo 2009: The “GLOBE at Night” citizen-science campaign has reached 10,000 contributed measurements during its 13 day campaign this year in March!

9 Marzo 2009: Finding a needle in a haystack might be easy compared to finding two very similar black holes closely orbiting each other in a distant galaxy. Astronomers from the National Optical Astronomy Observatory (NOAO) in Tucson have found what looks like two massive black holes orbiting each other in the center of one galaxy.

3 Marzo 2009: This issue highlights science being done with telescopes available through the broader "System" of telescope access, and includes articles on new and upcoming instruments for SOAR in Chile and WIYN on Kitt Peak.

25 Febrero 2009: Certainly one of the strangest objects in our Milky Way galaxy has been hiding as a variable X-ray source called SAX J1808.4-3658. This X-ray binary has been known to contain an accretion-powered millisecond pulsar located at a distance of 3,500 parsec (~11,500 light-years). It was also the first identified millisecond pulsar system among X-ray binaries. Recent observations with GMOS-S (Gemini Multi-Object Spectrograph – at Gemini South) have revealed a large periodic modulation of its quiescent optical emission. The observations show a light curve with a remarkably regular sinusoidal shape of ~0.4 magnitude in amplitude in r’ band (Figure 1). Conducted by the Canadian-Dutch team led by Zhongxiang Wang (McGill University), the new observations indicate that the light curve modulation is caused by irradiation of the companion star to the pulsar, and not by activity in the accretion disk. The pair is strange because it is comprised of an unusual couple: …

24 Febrero 2009: This image of R136, the massive star cluster at the center of the 30 Doradus nebula in the Large Magellanic Cloud was taken on Spartan’s second commissioning run on the SOAR telescope.

20 Febrero 2009: NOAO astronomer and U.S. IYA Project Director Stephen Pompea shows off the “Galileoscope” student telescope kit in Paris.

11 Febrero 2009: In the context of the currently favored cosmological Λ-Cold Dark Matter model of the universe, the formation and evolution of galaxies remains a major unsolved problem. In particular, the detailed evolution of the bulge and disk components of spiral galaxies is not well represented in current simulations. The data–model discrepancies do not necessarily reflect a failure in the ΛCDM model, but may indicate physical regimes and processes that are either poorly understood or difficult to implement in large simulations. Given the significant challenges faced by current galaxy formation models, guidance towards a true understanding of disk galaxies must come from an observational perspective such as the one described here using the Gemini Multi-Object Spectrograph. A very useful probe in discerning between formation scenarios is a detailed breakdown of the age, metallicity (Z), and kinematic properties of the stellar population (SP) content comprising bulges of all types. Information about both light- …

29 Enero 2009: NOAO astronomer and U.S. IYA Project Director Stephen Pompea shows off the “Galileoscope” student telescope kit at IYA opening ceremonies at UNESCO Headquarters in Paris.

22 Enero 2009: Stuart Ryder, Australian Gemini Scientist at the Anglo-Australian Observatory, and colleagues from Europe and South Africa have used the 8-meter Gemini North telescope in Hawai‘i and its laser guide star adaptive optics system to reveal a supernova (SN 2008cs) in a galaxy (IRAS 17138-1017) 250 million light-years away (Figure 1). This is the first supernova to be discovered using laser guide star adaptive optics. Along the way, the researchers also turned up a second, “historical” supernova, SN 2004iq, in the same galaxy. Stellar evolution theory, along with the recent identifications of actual supernova progenitors, indicates that only stars more massive than ~8Msun will end their lives as core-collapse supernovae. Assuming that the ratio of such stars to less massive ones—the initial mass function—is the same everywhere in the universe, then the observed rate of supernovae can be used to gauge the rate of star formation, across a wide range of …

16 Enero 2009: Dr. Timothy Beers of Michigan State University has been appointed to Chair the Gemini Science Committee starting on February 1, 2009. In this capacity Timothy will lead the effort to assure that Gemini's current and future scientific mission fulfills the needs or our user communities. The appointment is for a period of 2 years. Timothy Beers is presently University Distinguished Professor of Astronomy at Michigan State University, and Associate Director of the Physics Frontier Center JINA (Joint Institute for Nuclear Astrophysics). Although his Ph.D. thesis at Harvard University (1983) was on the nature of substructure in clusters of galaxies, for the past 25 years he has worked on surveys and analysis of metal-poor stars in the Milky Way, and on the formation and evolution of galaxies as revealed by their elemental and kinematical signatures. He is a participant in current studies of the Milky Way Galaxy as survey scientist for …

5 Enero 2009: The newest addition to the Gemini Legacy imaging program is a laser-guide-star enabled near-infrared image of the well-known planetary nebula NGC 7027 (Figure 1). NGC 7027 lies at a distance of about 3,000 light-years from Earth and is located in the direction of the constellation Cygnus. The nebula itself is approximately 14,000 astronomical units from end-to-end, about 140 times larger than our Solar System. NGC 7027 is a planetary nebula, so-named because early observers with small telescopes thought that these targets resembled fuzzy ‘planets’ in the sky. We now know that objects like NGC 7027 are not planets, but the name has stuck throughout the years. We also know that objects like NGC 7027 give us a tantalizing peek into the future of our own Sun. Toward the end of their lives, when they get close to exhausting all of the nuclear fuel they are born with, stars like the …

23 Diciembre 2008: The Subaru and Gemini Observatories are pleased to announce a jointly sponsored science meeting that will be held at Kyoto University, Kyoto Japan, between May 18-21, 2009. An estimated two-hundred and fifty participants, approximately half coming from each community, will meet to present research conducted at the two observatories and to explore possible collaborations. The two main goals of the conference are to promote a mutual understanding of both communities and to highlight the international nature of modern astronomy. Other goals are to: Better understand the Subaru and Gemini instruments and science programs Foster scientific collaborations Define key areas of 'niche science' for both observatories Initiate scientific collaboration for, and with respect to, the International Year of Astronomy in 2009 The Scientific and Local Organizing Committees have recently been appointed. The SOC is led by two co-chairs Masashi Chiba (Tohoku University) and Timothy C. Beers (Michigan State University). The LOC …