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2 December 2002: The Large Magellanic Cloud, a small satellite galaxy at a distance of about 50,000 parsecs, is a prime target in which to probe the chemical evolution of stars. Because this galaxy has a different star formation history than our own galaxy, the properties of its stars are different. Variations in galaxy evolution can lead to differences in chemical composition, which result in stars that noticeably differ in the later phases of their evolution. Measuring and understanding these chemical differences help unravel the physics of the complexes processes of nuclear burning and mixing that take place in the red giant and later phases. Within a given stellar population in a galaxy, chemical evolution is driven primarily by stellar nucleosynthesis, with the dispersal of the processed material back into the galactic interstellar medium (ISM). This heavy-element enrichment over time depends on such processes as star formation history, internal stellar evolution and nucleosynthesis …

6 November 2002: Approximately 110 astronomers will meet in Kona during November 3-8, 2002, to discuss the nucleus of our Milky Way. Called "The Central 300 Parsecs," the conference has been locally organized mainly by Gemini-North staff and is sponsored by Gemini and several other observatories on Mauna Kea. Gravity and frictional forces inevitably cause the centers of galaxies to acquire mass densities much higher than that of the outer regions. Even a normal-looking spiral galaxy such as ours might be expected to contain almost the entire galactic astronomical zoo: stars of all masses and evolutionary states, white dwarfs, nebulae, dust clouds, neutron stars, and even black holes - all packed together in a tight swarm. The nucleus of our galaxy is already known to contain a wide variety of astrophysical phenomena. Although it is 25,000 light years away, it is by far both the nearest and brightest galactic nucleus. Thus it can …

6 November 2002: Perhaps flung from the Galactic Center's innermost cluster of hot stars some 20,000 years ago, the massive star IRS-8 is moving at supersonic speed through high density gas. Located 8000 parsecs from the Sun in the direction of Sagittarius, the nucleus of the Milky Way is host to numerous high energy phenomena including a supermassive black hole of approximately three million solar masses which defines the dynamic center of our galaxy. The nucleus also contains a number of young clusters of recently formed hot and massive stars, peculiar radio-emitting filaments of ionized gas, supernova remnants, and a number of bright and compact objects whose natures and origins are unclear. Because of the high dust content along the line of sight to the Galactic Center, it has been impossible to observe this region at ultraviolet and optical wavelengths. New tools such as infrared array detectors combined with adaptive optics on large …

9 October 2002: SBS 0335-052 is a gas-rich dwarf galaxy at a distance of 170 million light-years (52 Mpc). It is the second most metal-poor galaxy known, with a heavy metal content only 1/40th that of the Sun. Such a low metallicity means that this galaxy contains significantly lower quantities of the heavy elements produced by the process of nucleosynthesis in stars. This lack of metals could be because the galaxy is very young. Another possibility is that SBS 0335-052 is an old galaxy that has experienced a very low star formation rate throughout its lifetime. Canadian Ph. D. student Stephanie Plante (Universite Laval, Quebec) and French astronomer Marc Sauvage (Service d'Astrophysique, Saclay) used OSCIR on Gemini North to image SBS 0335-052 in the mid-infrared at 10.8 and 21 microns. Their images revealed a massive supercluster of young stars with a total mass equivalent to 2 million times the mass of the Sun …

26 September 2002: A US-UK team led by Gemini South astronomer Michael Ledlow, using the Gemini Multi-Object Spectrograph (GMOS) on Gemini North, has obtained a spectrum from the optical counterpart of the most distant "dusty" galaxy known. This object was selected for study based on a detection at submillimeter wavelengths using SCUBA* on the JCMT (Cowie, Barger, & Kneib 2002). The optical counterpart was found in deep multiwavelength imaging from the Kitt Peak National Observatory, but its nature was not understood (only a handful of SCUBA/submm galaxies have measured spectra). Gemini was able, with its great light gathering power, to obtain a spectrum that allows an analysis of this distant galaxy that is thought to represent some of the most massive galaxies of the early universe. Michael Ledlow and his collaborators studied the optical counterpart of the submillimeter source, SMMJ09431+4700 that is seen through an intervening galaxy cluster (Abell 851) at redshift 0.41. …

10 September 2002: From the Milky Way Suburbs to the Edge of the Universe This deep image obtained with the Gemini Multi-Object Spectrograph with the Gemini North Telescope shows a dramatic view of the universe as it can be revealed by the new generation of large ground-based telescopes. Not unlike the Hubble Space Telescope which is unhindered by the Earth's atmosphere, the present generation of very large ground based telescopes allows a unique view of the universe going from within our galaxy (by probing the faintest stars of the Milky Way) to the edge of the universe (like the central green object of this image which is probably at more than 10 billion light years away). Most of the galaxies appear faint because their light has come from so far that it traveled for much of the age of the universe. Many of these giant stellar systems, spirals and ellipticals, are as large …

27 August 2002: Exploring mass sub-structure in the Einstein Cross lensing galaxy A gravitational lens is created when a massive foreground object (a large intervening galaxy in this case of the Einstein Cross) bends and amplifies the light from a far more distant object (a quasar in this case) directly behind it. In certain circumstances, the background object may be distorted or even multiply-imaged into two or four images. The Einstein Cross (Q2237+0305) is such a 4-image lens, where the bulge of a nearby spiral galaxy is lensing a very distant quasar. In the case of the Einstein Cross, the more distant quasar appears much brighter than the intervening galaxy and four images of the same quasar are formed. Without the intervening galaxy, the quasar image would be a single object of much fainter magnitude. The goal of the CIRPASS near-infrared spectroscopy program on the Einstein Cross is to explore mass substructures of …

13 August 2002: The children and teachers of Hawai'i and Chile will be the first to benefit from a novel educational program made possible by Gemini Observatory's new high-speed Internet link that connects the twin telescopes on both hemispheres. Observatory Director Dr. Matt Mountain announced today the new Gemini StarTeachers Exchange Program between Hilo and its Sister City of La Serena, Chile - the two host communities of Gemini Observatory. The announcement was made from Gemini's Hilo Base Facility during a world-wide "virtual inauguration" demonstrating the Internet technology. (See related press release, "Celestial Cybernetics") "This is a learning process for all of us," Dr. Mountain said. "We're hopeful this first exchange program will provide us with valuable data and experience on the educational use of our evolving audio-visual Internet capabilities. We want to refine the technology, so we can continue and expand these community-type programs throughout our international observatory partnership." The goal of …

3 June 2002: On Monday afternoon, June 10, Big Island residents had the opportunity to safely view a partial solar eclipse where the Moon covered about half the Sun's surface. The public was invited to attend a Family Astronomy Afternoon to view the partial solar eclipse from 1 to 4 p.m. at the Gemini Observatory headquarters at University Park on the upper campus of the University of Hawai'i at Hilo (off Komohana). "This is a unique opportunity to view a partial solar eclipse and view the Sun safely through a telescope," said Dr. Richard Crowe, Professor of Astronomy at UH-Hilo. "I anticipate that we will also have some nice views of sunspots, if Hilo's weather cooperates." The event was jointly sponsored by the Hilo Astronomy Club, the UH-Hilo Department of Astronomy and the Gemini Observatory. At its maximum coverage, which occurred in Hilo at 2:47 p.m., the Moon hid almost exactly half the …

29 April 2002: Taken on April 23, 2002

4 April 2002: Arden Bercovitz, Ph.D., is a scientist portraying a scientist, creativity coach and keynote speaker recognized by the National Speakers Association. Dr. Bercovitz has performed as Einstein for over 10 years and his acclaimed characterization of the famous scientist has received praise from students, the media and scientists alike. Since asking questions was critical to Einstein's genius, the public is encouraged to question Einstein. Bercovitz, as Einstein, answers in character, weaving stories and answers from a wealth of Einstein quotes and powerful anecdotes that show Albert Einstein as not just a scientist, but also a visionary and humanist. Enlivened by dramatizations based closely on Einstein's writings and recollection of experiences, Bercovitz shares Albert's unique genius to help children and adults expand their thinking skills and broaden their horizons. All programs are free but seating will be limited and provided on a first-come-first-served basis. All programs are sponsored by the Gemini Observatory …

22 February 2002: Phoenix, a high resolution infrared spectrograph, originally built for use on the NOAO 4-m telescopes at Kitt Peak and Cerro Tololo, underwent commissioning on Gemini South in December 2001. The first science observing programs were performed in early February 2002. They comprised a Demonstration Science program (described below) and individual science projects from the Gemini queue. Both the commissioning and the science runs were highly successful. Introduction to Demonstration Science Our universe initially was virtually entirely hydrogen and helium, as a result of the Big Bang. The heavier elements (which astronomers call "metals") that now make up a small fraction of the universe's mass and our sun's mass (but much of the mass of the earth, and our bodies) were made inside previous generations of stars, which exploded and ejected their material into space. Studies have shown that spiral galaxies, including our Milky Way, have higher abundances of "metals" in …

1 June 1999: Observations of globular clusters teach us how the first generation of stars in our Galaxy formed some 12 to 15 billion years ago and how they have evolved ever since. Globular clusters are extremely dense stellar environments that typically contain between one hundred thousand to one million stars. The density of these star cities presents us with a wealth of information on stars of all sizes but also presents a great challenge – how can we peer into the very heart of such a dense star cluster? Gemini, with its excellent image quality, can provide extremely sharp pictures that deblur and deblend the star images and allow observations right into the very heart of these oldest stellar environments. The optical picture on the left is sharp and clear because of the good atmospheric conditions on Mauna Kea and the excellent optical quality of the Gemini telescope. Yet NGC 6934 contains …