Announcements 2004

24 December 2004: The staff of the National Optical Astronomy Observatory wishes you all the best this holiday season.

20 December 2004: Using adaptive optics on the Gemini North and Keck II telescopes on Mauna Kea, Hawai’i, a U.S. team has discovered a new phenomenon in the atmosphere of Saturn’s largest moon Titan. Unlike previous observations showing storms at the south pole, these new images reveal atmospheric disturbances at Titan’s temperate mid latitudes—about halfway between the equator and the poles. Read the Gemini Press Release.

13 December 2004: Discovered just this past summer, Comet Machholz continues to brighten toward being visible with the unaided eye in both the northern and southern hemispheres. This image was taken at the Kitt Peak Visitor Center Observatory on December 11, 2004.

7 December 2004: Gemini staff have successfully repeated the coating of a 8-meter primary mirror with protected silver during a 9-day shutdown period. This is the second successful silver coating of a Gemini primary mirror and was applied on Thanksgiving Day in a 7-hour process interrupted by an intense hail storm at midday. This is the second time a Gemini primary mirror has been coated with protected silver (Gemini South was coated in May 2004) and now all key optical surfaces (primary, secondary and science fold mirrors) are coated. This is a milestone in front surface mirror coating technology. The result is a dramatic reduction in the thermal emissivity of the telescope systems—down to an unprecedented level of about 2% or lower. Following the successful coating, team members cheered as reflectivity values were announced and they realized that the coating was successful. The application of protected silver coatings on both Gemini telescopes is …

2 December 2004: This image of the massive N11 complex is featured on the cover of the December 2004 NOAO Newsletter. Numerous star forming regions and shells blown out by supernovae and strong stellar winds can be seen. The data used to create the image were taken with the University of Michigan Curtis Schmidt telescope at Cerro Tololo Inter-American Observatory near La Serena, Chile, as part of the Magellanic Clouds Emission Line Survey (MCELS).

30 November 2004: Kevin Luhman (Harvard-Smithsonian Center for Astrophysics), Dawn Peterson (University of Rochester) and S. T. Megeath (also CfA) used the newly commissioned Gemini Near Infrared Spectrograph (GNIRS) on Gemini South to determine the nature of the low-mass object OTS 44. The observations of the faint infrared object confirmed that it is a very low-mass, newborn brown dwarf and the lowest mass brown dwarf found to date in the Chamaeleon I cloud complex. The Chamaeleon I cloud complex is a nearby star-forming region located about 170 parsecs (554 light-years) away from us toward the constellation of Chamaeleon. From the strength of the water vapor (steam) absorption band around 1.5 and 2 microns, and in comparison to other low-mass stellar objects, the team determined OTS 44 to be of very late spectral type M9.5 (geminiann04018a). They estimate its effective temperature at 2300 K. Using the flux in the H band and the object’s …

4 November 2004: Using archived science verification data from the Hokupa'a/QUIRC Adaptive Optics system on Gemini North, a French/US team of astronomers led by Jean-Pierre Maillard of the Institut d’Astrophysique de Paris has confirmed the physical association of a cluster of massive stars in the infrared source IRS 13 near the center of the Milky Way galaxy. The team also used data from Hubble Space Telescope, the Chandra X-Ray Observatory, the Canada-France-Hawai’i Telescope (CFHT), and the Very Large Array to complement the Gemini data. The Gemini observations consisted of deconvolved H and Kp band images that identified the existence of two formerly undetected sources within the eastern component of IRS 13 (called IRS 13E). When the Gemini data were used in conjunction with longer and shorter wavelength observations, it was possible to conclude that these sources were massive stars comparable to the stars of the same type which are exceptionally concentrated in the …

27 October 2004: Closest Known Brown Dwarf has a Companion. While searching for planet-sized bodies that might accompany the nearby star system Epsilon Indi, astronomers using the Gemini South telescope in Chile made a related but unexpected detection. Widely observed by telescopes on the ground and in space, Epsilon Indi was known to host an orbiting companion, called Epsilon Indi B, which was discovered last year and is the nearest known specimen of a brown dwarf. Brown dwarfs are very small, cool stars thirty to forty times more massive than Jupiter but of similar size. Despite all the observing, it took the combination of Gemini's powerful infrared capabilities and the extremely sensitive spectrograph/imager called PHOENIX (without adaptive optics) to reveal the more elusive body. "Epsilon Indi Ba is the closest confirmed brown dwarf to our solar system," says Dr. Gordon Walker (University of British Columbia, Vancouver, Canada), who led the research team that …

22 October 2004: The third data release (DR3) from the NOAO Deep Wide-Field Survey (NDWFS) is now available. This release includes all the Mosaic-1 optical and ONIS K-band imaging of the 9.3 square degree Boötes survey field. Catalogs of objects detected in the images are also provided. The images can also be obtained via the NOAO Science Archive.

19 October 2004: Eight meter-class telescopes such as Gemini, the Very Large Telescope (VLT), Subaru and Keck have opened up the high-redshift universe for detailed study. Several galaxies out to redshifts of z ~ 6.6 are now known and Gemini has played a significant role in their discovery: "Searching for the end of the cosmic dark ages with GMOS", "Gemini Probes Galaxy Evolution a Billion Years After the Big Bang". Finding even more distant galaxies is particularly important to our understanding of the formation of the very first stellar objects in the history of the universe, and of the ensuing reionization of the intergalactic medium. This epoch of “first light” at redshifts between ~7-15 marked the end of the early universe’s dark ages – a time when the universe was filled with mostly neutral hydrogen. Recently, Pelló et al. (Astronomy and Astrophysics, vol. 416, p. 35, 2004) identified a possible highly magnified object …

9 October 2004: A stunning image released today by the Gemini Observatory captures the graceful interactions of a galactic ballet, on a stage some 300 million light years away, that might better be described as a contortionist's dance. The galaxies, members of a famous troupe called Stephan's Quintet, are literally tearing each other apart. Their shapes are warped by gravitational interactions occurring over millions of years. Sweeping arches of gas and dust trace the interactions and possible ghost-like passage of the galaxies through one another. The ongoing dance deformed their structures while spawning a prolific fireworks display of star formation fueled by clouds of hydrogen gas that were shocked into clumps to form stellar nurseries. This unprecedented image of the cluster provides a unique combination of sensitivity, high resolution and field of view. "It doesn't take long to reach an incredible depth when you have an 8-meter mirror collecting light under excellent conditions," …

5 October 2004: Astronomers including Steve Howell of NOAO-WIYN have used the Gemini North and Keck II telescopes to peer inside a violent binary star system to find that one of the interacting stars has lost so much mass to its partner that it has regressed to a strange, inert body resembling no known star type. Gemini Press Release

27 September 2004: Mira stars, red giant variables that have been studied for 400 years, are generally half as large in diameter as had been believed, thanks to an opaque shell of water vapor and other molecules that surrounds them. A team including Steve Ridgway of NOAO used the IOTA interferometer on Mount Hopkins, AZ, to make this discovery. Read more in the Astronomy and Astrophysics press release, Forseeing the Sun’s Fate.

21 September 2004: After more than five years of planning and development, the Gemini Science Archive Version 1 (GSA V.1.0) was released on September 20, 2004. The concept of an astronomical science archive, where data from a telescope is stored safely for posterity, is not new. What makes the GSA unique is that it allows quick, easy and complete access to all aspects of the science data. This was the vision of the Gemini archive first proposed in the late-1990's by Fred Gillett and others. This updated version replaces a prototype that had been available since November 2003 and includes many new and improved features. Access to Gemini data through the GSA is unrestricted once users obtain a user account that can be obtained by completing a simple registration form. The GSA can be accessed via the CADC homepage at URL http://cadcwww.hia.nrc.ca or directly at http://cadcwww.hia.nrc.ca/gemini The first thing a user will notice …

17 September 2004: 2004 September 7, 2004 - Galactic Contortionists Captured by Gemini August 25, 2004 - MICHELLE and HIRES Observing Times are Traded August 11, 2004 - Searching for the end of the cosmic dark ages with GMOS July 21, 2004 - Gemini South Obtains First High-Resolution Image Of Supernova Dust July 9, 2004 - A high abundance of massive galaxies 3-6 billion years after the Big Bang June 30, 2004 - Gemini, Keck and Subaru Combine Efforts to Study the Assembly of a Large and Distant Galaxy Cluster June 9, 2004 - Gemini South is First 8-10 Meter Class Telescope With Protected Silver Coatings May 25, 2004 - Cosmic Powerhouses Dwell In Humble Homes May 18, 2004 - Gemini opens a new window into the era of galaxy assembly May 4, 2004 - Gemini Provides New Insights on the Origins of Jupiter and Saturn "Irregular" Satellites April 12, 2004 - Orphan …

8 September 2004: This stunning image from the Gemini Observatory’s Multi-Object Spectrograph captures the graceful interactions of a galactic ballet, on a stage some 300 million light-years away. The galaxies are literally tearing each other apart, as the shapes of four of them are warped by mutual gravitational interactions. The fifth galaxy, at the top center of the image (NGC 7320) is thought to be much closer to us than the others, so it remains unaffected by the dance of galaxies behind it. It is further distinguished in this image by numerous red blobs indicating hydrogen-rich star forming regions.

31 August 2004: In theory all Planetary Nebula should look like this one: a nearly perfect sphere with a brightened limb. The reality is that most nebulae are found in a wide variety of shapes and colors. Round ones like PK 40-0.1 are actually a rarity in the Universe.

25 August 2004: Over the past few years, a more coordinated approach to the building and using of new instruments for very large telescopes has gained strong support among science policy makers and, increasingly, among scientists themselves. In this spirit, we are pleased to announce that Gemini and Keck have agreed to exchange five nights of observing time at each facility in semester 2005A. The Gemini user community will have access to five nights of HIRES, the optical high-resolution spectrograph on Keck I. In return, Keck users will have access to the mid-infrared imager/spectrograph MICHELLE on Gemini North for five nights. The nights will be "classically" scheduled. Gemini's MICHELLE is a mid-infrared (8-25 micron) imager and spectrometer. In its spectroscopic mode, MICHELLE allows observations with resolution of R = 200, 1000, 3000 and 20,000 at 10 and 20 microns. MICHELLE was recently re-commissioned on Gemini North after being on UKIRT for much of …

13 August 2004: A team of U.S. astronomers reports the discovery of extremely high rates of star formation (more than 11 solar masses per year) in one of the most distant known galaxies in the Universe, some 12.8 billion light-years away. Astronomers traced the galaxy's starburst activity by measuring light emitted in the Lyman-alpha emission line, using deep multi-object spectroscopy conducted at the Gemini Observatory with GMOS-North.

11 August 2004: A team of U.S. astronomers led by James Rhoads from the Space Telescope Science Institute, reports the discovery of extremely high rates of star formation in one of the most distant known galaxies in the universe. LALA J142442.24+353400.2, named for the survey in which it was discovered and its celestial coordinates, lies at a redshift of 6.535, which puts it 12.8 billion light-years away and appearing as it looked some 850 million years after the Big Bang. This faint, distant galaxy is fabricating stars at a rate of more than 11 solar masses per year, a frenetic pace among galaxies at this distance and epoch in the early universe. Astronomers traced the galaxy’s starburst activity by measuring light emitted in the so-called Lyman-alpha emission line, using deep multi-object spectroscopy conducted at Gemini Observatory with GMOS-N and the Keck Observatory with the Deep Imaging Multi-object Spectrograph (Deimos). The galaxy was first …