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16 Diciembre 2002: Many detailed features in this spiral galaxy in the constellation Canes Venatici have been brought out by drastically compressed image mapping: an extremely bright inner region surrounded by a blue ring of young star clusters, a fainter yellowish region of older stars also surrounded by traces of young stars, and even further out, a very much fainter outer ring.

2 Diciembre 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 …

25 Noviembre 2002: his revealing image combines optical data from the 0.9-meter telescope on Kitt Peak with radio data from the Very Large Array in New Mexico and the Westerbork Synthesis Radio Telescope in the Netherlands.

14 Noviembre 2002: Marian Gillett, right, with her children, Michael Gillett and Denuta Gessner, stand before the plaque which honors her deceased husband, Dr. Fred Gillett (inset), in a naming ceremony of the Gemini North telescope, November 13, 2002, on Mauna Kea, Hawai'i.

7 Noviembre 2002: This excellent image of M27, a planetary nebula in the constellation of Vulpecula, was taken at the 3.5-meter WIYN telescope using the Mini-Mosaic imager.

6 Noviembre 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 Noviembre 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 …

22 Octubre 2002: An unobtrusive arc of blue stars stretching above the iconic galaxy Centaurus A represents the lingering signature of an episode of galactic cannibalism that is surprisingly recent and, astronomically speaking, quite nearby.

10 Octubre 2002: Tucson Mayor Robert Walkup and three students from the Indian Oasis Middle School in Sells cut the ribbon at the official opening night of the Space Weather Center exhibit at the Kitt Peak Visitor Center.

9 Octubre 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 …

27 Septiembre 2002: Instrument at the CTIO Blanco 4-meter telescope has obtained this first-light image of globular cluster 47 Tucanae taken in the infrared H-band.

26 Septiembre 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. …

18 Septiembre 2002: Taken at Kitt Peak has been turned into a popular poster available for purchase at the Visitor Center.

10 Septiembre 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 …

9 Septiembre 2002: Was discussed several times at the recent Workshop on Science Requirements for Mitigation of Hazardous Comets and Asteroids.

27 Agosto 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 Agosto 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 …

4 Agosto 2002: is located in the constellation of Sagittarius. This stunning image of the much-photographed, dynamic cloud of gas and dust, was taken at the Gemini North Observatory with the GMOS instrument, which uses software developed by NOAO.

15 Julio 2002: Is a richly populated star cluster in the Milky Way whose stellar population has surprising similarities to the Sun's composition.

20 Junio 2002: Is the bluish dot to the right of the center of the galaxy NGC 5018 in this image taken by the 0.9-meter telescope at Cerro Tololo Inter-American Observatory in Chile on 14 June 2002.