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27 Septiembre 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 Septiembre 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 Septiembre 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 Septiembre 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 Agosto 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 Agosto 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 Agosto 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 Agosto 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 …

27 Julio 2004: Infrared observations of SN 1987A made in October 2003 as part of the checkout of the new Thermal-Region Camera Spectrograph (T-ReCS) instrument on Gemini South have revealed emission from a cool dust ring that is surprisingly luminous. It co-exists with hot gas components left over from the relic equatorial ring featured prominently in data from other observatories in wavelengths from X-ray to radio.

21 Julio 2004: Infrared observations of Supernova 1987A made in October 2003 as part of the “checkout” of the new Thermal-Region Camera Spectrograph (T-ReCS) instrument on Gemini South have revealed dust emissions at a wavelength of 10 microns, corresponding to a temperature of about 150 degrees Kelvin. They are coming from a cool dust ring that is surprisingly luminous. It co-exists with hot gas components left over from the relic equatorial ring so prominently featured in images and data from other observatories in wavelengths from X-ray to radio. This T-ReCS observation is the first detection of mid-infrared emission from the ejecta ring of SN1987A in five years. The similarity of Gemini’s 10-micron image with those taken in X-ray images obtained by the Chandra Observatory, and at radio frequencies from the Australian National Telescope Facility, suggests that the thermal emission is due to the recent heating of pre-existing dust in the equatorial ring by …

16 Julio 2004: An image of N11 in the Large Magellanic Cloud, taken with the Curtis Schmidt telescope at Cerro Tololo Inter-American Observatory (CTIO) as part of the Magellanic Clouds Emission-Line Survey (MCELS). This color image was produced using three separate exposures taken in hydrogen, sulfur and oxygen bandpasses. It was used to support the July 2004 release by the Hubble Heritage project.

8 Julio 2004: Some 5,000 light years from Earth, toward the asterism of Sagittarius, lies the emission nebula NGC 6559. Hydrogen gas is responsible for the diffuse red glow, while dark clouds of dust absorb much of the nebula's star light. Smaller dust particles scatter the blue light from the bright stars in the bottom half of the image, creating the beautiful blue and purple reflection nebulosity.

7 Julio 2004: A Gemini team led by Karl Galzebrook of Johns Hopkins University has just released some spectacular results obtained from the Gemini Deep Deep Survey (GDDS) in the British journal Nature. The team found that at last two-thirds of massive galaxies appeared after the first 3 billion years following the Big Bang. However, a significant fraction of them are already in place in the early Universe. The GDDS was completed using the Gemini North telescope and the Gemini Multi-Object Spectrograph (GMOS-N). The team observed four widely-separated 30 arcmin2 fields. The spectroscopic exposure time for each field was about 30,000 seconds. The spectrograph was operated in the Nod & Shuffle mode. This technique enables the removal of contamination by the earth’s atmospheric luminescence to a high degree. Spectra of several hundred distant galaxies were obtained and measured. As has been suspected, massive, evolved galaxies are found at an epoch earlier than half …

30 Junio 2004: Large galaxy clusters represent the largest gravitationally stable assemblies of matter in the universe. Massive clusters of galaxies consist of thousands of galaxies and vast quantities of extremely hot intergalactic gas all held together by gravity. It is believed that clusters of galaxies grow in size and in number through time and we see many more galaxy clusters in the nearby (recent) universe than in the distant past. The assembly and growth of massive clusters involve complex interactions between dark matter, diffuse gas, and thousands of individual galaxies. The physical details of these interactions are currently not fully understood. Both computer simulations and theoretical work predict that the growth process of massive clusters is highly non-isotropic with the in-fall of matter and galaxy mergers occurring along preferred directions. The coalescence and funneling of matter should produce highly correlated structures in space, enhancing visibility in these preferred directions. This is referred …

29 Junio 2004: This loose, widely spaced open cluster is found in the constellation Cygnus, about 800 light-years away. Also known as NGC7092, it has around 30 members and is two to three hundred million years old. This picture is a combination of 33 dithered frames in BVR colors taken with the Mosaic camera at the WIYN 0.9-meter telescope on Kitt Peak, near Tucson, Arizona

18 Junio 2004: Astronomers using a combination of data sets from the Mayall telescope at Kitt Peak, including the NOAO Deep Wide-Field Survey (image above), have found a galaxy that formed when the Universe was just six percent of its present age, suggesting the "dark ages" of the early universe ended in a patchy, gradual process.

3 Junio 2004: This three-color composite image of spiral galaxy NGC 4402 shows several key lines of evidence for the galaxy being stripped bare of its star-forming material by its violent ongoing encounter with the hot gas in the center of the Virgo galaxy cluster, as NGC 4402 falls into it. Released at the AAS meeting in Denver.

26 Mayo 2004: This image of Comet C/2001 Q4 (NEAT) was taken with the Mosaic I camera at the WIYN 0.9-meter telescope at Kitt Peak National Observatory near Tucson, AZ, on May 7, 2004. The comet will remain visible for several weeks with binoculars and small telescopes just after sunset, high in the western sky. See also NOAO Press Release 04-04.

21 Mayo 2004: Combining images from the Hubble Space Telescope (HST) and the WIYN Telescope on Kitt Peak, near Tucson, Ariz., this image is a color-coded picture of the archetypal starburst galaxy M82. It shows the horizontal stellar disk of the galaxy, which harbors its active star formation, and a perpendicular supergalactic wind of ionized gas powered by the energy released in the starburst. See also University of Wisconsin-Madison press release.

18 Mayo 2004: May 18, 2004 Using a sophisticated technique called Nod & Shuffle, combined with the Gemini Multi-Object Spectrograph, ultra-deep spectra of several hundred distant, elusive galaxies were captured. These observations by the Frederick C. Gillett Gemini North Telescope help to paint a new picture of the nature and evolution of galaxies some 7 - 10 billion years ago. Multiple recent discoveries of galaxies at very high redshifts have opened a fascinating window into what happened less than a billion year after the Big Bang. However, there is a more recent time interval in the past history of the universe that has remained relatively unexplored until very recently. The so-called "redshift desert" corresponds to an era when the universe was between one-third and one-half its present age (between redshifts 1 < z <2). Relatively little is known of the galaxies in this period due to a combination of intrinsically faint galaxy spectra …