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4 Noviembre 2003: November 4, 2003 A group of astronomers has recently studied the chemical make-up of distant galaxies in the "redshift desert," which is a virtually unexplored region of space between eight billion and ten billion light years away. Because the light from these galaxies moves at a finite speed, the galaxies are being seen when the Universe was between 20% and 40% of its present age. Studying the properties of galaxies at this particular time is important because it corresponds to a special age in the history of the Universe - a time during which it is thought to have made most of its stars. These observations were undertaken using the Gemini North telescope and a uniquely capable instrument, the Gemini Multi-Object Spectrograph (GMOS), which is able to target extraordinarily faint galaxies using a newly developed technique known as "nod and shuffle." This work is reported in "The Gemini Deep Deep …

29 Octubre 2003: ...Is a message that the StarTeachers successfully delivered to thousands of students in Chile and Hawai`i. The second-half of the inspiring StarTeachers program began on Saturday, October 11, in Waikoloa, Hawai`i, with a welcoming gala. During the gala, Gemini was honored to receive the Gabriela Mistral Medal for excellence in education from the Chilean Ministry of Education. The gala event kicked-off two weeks of teaching and cultural exchange. The StarTeachers have been busy on the Big Island. More images are provided in the StarTeacher's Photo Album. Additional information about the individual teachers and background information on the StarTeachers program is also available at our website. The StarTeachers spent most of their time in schools and classrooms in East Hawaii infusing students and other educators with their love of science, astronomy and culture. They visited 9 schools total with focused efforts at the Hawaiian StarTeachers' home schools - Keaau High School, …

24 Octubre 2003: NOAO has completed construction and testing of the Gemini Near Infrared Spectrograph (GNIRS). The instrument left Tucson on October 24 on its way to be mounted on the Gemini South telescope on Cerro Pachón in Chile, where it arrived on October 27 (see bottom image). This multi-million dollar, long-slit spectrometer will help astronomers make measurements of the chemical abundances of stars in other galaxies, the conditions at the centers of other galaxies (including very distant young objects) and the initial mass functions for very young star clusters.

22 Octubre 2003: The Gemini Observatory recently reached an important milestone - successful coating of the secondary mirror on Gemini South with silver. Previously, with aluminum coatings on both primary and secondary mirrors, Gemini's combined emissivity was 3.8%. Reaching this new milestone, we are increasingly confident that achieving our ambitious goal of 2% total telescope emissivity is attainable. Reflectivity and emissivity are two measures of a mirror's performance. A highly reflective mirror is desirable in any optical telescope in order to maximize the amount of light reaching the science instrument. Ideally, a coating should reflect as close to 100% of the light that strikes it. In the thermal infrared region of the spectrum, however, a mirror coating emits a great deal of infrared radiation, and the statistical "noisiness" of this emission reduces an infrared instrument's sensitivity to emission from astronomical sources. The emissivity of an optical surface is defined as the ratio between …

6 Octubre 2003: This image of the clouds of gas and dust next to the “neck” and “body” of the Pelican Nebula was produced by an NOAO Survey Program known as the Deep Imaging Survey of Nearby Star-Forming Clouds, led by John Bally of the University of Colorado and Bo Reipurth of the University of Hawaii.

2 Octubre 2003: Daniel Stern of the Jet Propulsion Laboratory and his USA-UK-Chile team of astronomers (including Gemini-South Astronomer Michael Ledlow) used the visiting instrument FLAMINGOS, a multi-object near infrared spectrograph at Gemini South to study the high redshift quasar SDSS J083643.85+005453.3 (SDSS J0836+0054). SDSS refers to the Sloan Digital Sky Survey, where the quasar was first discovered. The authors report their findings in "Gemini-South+FLAMINGOS Demonstration Science: Near-Infrared Spectroscopy of the z = 5.77 Quasar SDSS J083643.85+005453.3", The Astrophysical Journal Letters, 10 October 2003. Both CIV (at 1549 Angstroms) and CIII] (1909 Angstroms) were detected in the quasar at a redshift of z = 5.774 +/- 0.003 (See Figure 2). The new redshift derived from these lines is more accurate than the previous optical estimate (z=5.82), based on a single broad line, Lyman alpha (See Figure 1). Because of its high redshift and foreground absorption by our own galaxy, the quasar is invisible …

30 Septiembre 2003: 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. The nearest known specimen of a brown dwarf, Epsilon Indi B (now Ba), has a cooler and less massive companion: Epsilon Indi Bb. This discovery was made with the NOAO-built PHOENIX high-resolution spectrometer, using a narrow-band filter within the J-band, and without the aid of adaptive optics. The separation between Epsilon Indi Ba and Bb is 0.7 arcsecond.

25 Septiembre 2003: This nebula, also known as M20, gets its distinct look from dust lanes that seem to divide the nebula into three parts. Its distance is estimated at approximately 5,000 light-years and it can be found in the constellation Sagittarius. This image was taken at the Kitt Peak Visitor Center 20" telescope as part of the Advanced Observing Program.

2 Septiembre 2003: This montage of galaxy images from the Survey for Ionization in Neutral Gas Galaxies (SINGG) is featured in the Science Highlights section of the September 2003 NOAO/NSO Newsletter, which is online now.

2 Septiembre 2003: The deflection of light by the deep gravitational potential of galaxy clusters can be harnessed to greatly increase the effective collecting area of astronomical telescopes. Mark Swinbank (Ph.D. student at the University of Durham, U.K.) and his international team used Gemini's Multi-Object Spectrograph with Integral Field Unit (GMOS-IFU) on The Frederick C. Gillett Gemini Telescope (Gemini North) to exploit the rich galaxy cluster A 2218. They used A 2218 as a magnifying glass to observe distant background galaxies at a comparable level of detail to galaxies at redshift z ~ 0.1. This work is part of Mark's Ph. D. project––to explore the Tully-Fisher relation and chemical abundance gradients in distant young galaxies. Swinbank et al., report on their first result of spatially-resolved [OII]3727 nebular gas emission from a lensed galaxy at a redshift z=1.034. This corresponds to an epoch half the present age of the universe. Using a detailed model …

19 Agosto 2003: PHOENIX was used to sample multiple stellar atmospheres and has revealed tantalizing clues that neutrino interaction during the supernovae explosion of massive stars is involved in the genesis of fluorine. PHOENIX uses a Gemini supplied 1024 x 1024 InSb Aladdin II array. Despite our awareness of fluorine's unique properties, its astrophysical origin is not well understood. Like most heavy elements, fluorine is a product of nuclear reactions in the hot cores of stars during various phases of their evolution. Furthermore, fluorine is not easy to observe in the universe, and very few spectroscopic measurements of fluorine in stars exist. Until the recent Gemini work reported here, only a meager set of data for a few stars in our own Milky Way was available. A spectroscopic program conducted at Gemini South, located on Cerro Pachón, Chile, has changed this picture. Katia Cunha (Observatório Nacional, Brazil) led a PHOENIX team of researchers …

11 Agosto 2003: This planet has captured the public’s imagination like no other in our solar system. As it nears its closest approach to Earth in some 60,000 years, Mars offers observers spectacular views such as this one taken on August 3, 2003 at the Kitt Peak Visitor Center 20-inch telescope.

6 Agosto 2003: High spatial resolution NIRI images taken in the 1.69-micron methane absorption band expose the detailed structure and varying chemistry of the clouds high in the Jovian atmosphere. The image of Jupiter was obtained as part of a systems check for the Gemini Near-Infrared Imager (NIRI) and was also used for a contest in which a Canadian elementary school student selected Jupiter as a target for Gemini. The Canadian Gemini Office located at the Herzberg Institute of Astrophysics in Victoria, BC, together with the Canadian Gemini Scientist sponsored a contest for Canadian school children. The aim was to make students more aware of astronomy in general and the Gemini Observatory in particular. Each entrant submitted a short paragraph on their favorite object in the sky and the winners were selected on the basis of the originality of the object and the reasons why it was their favorite celestial object. Two prizes …

23 Julio 2003: As a part of commissioning and engineering runs at the Frederick C. Gillett Gemini North Telescope in June and July 2003, the mid-infrared imager and spectrograph MICHELLE was used to image the young planetary nebula NGC 7027. Planetary nebula is the name given to the gas ejected from, and heated by, a low to intermediate mass star as the star makes the transition from red giant to white dwarf. As the radiation pressure from the contracting and heating core of the red giant causes the star to lose its outer atmospheric layers, the intense ultraviolet radiation from the core raises the temperature of those layers to tens of thousands of degrees Kelvin, causing the gas to glow. The planetary nebula phase of stellar evolution lasts only a few tens of thousands of years before the gas is so distant from the star that it no longer glows. NGC 7027 is …

8 Julio 2003: This striking image of the Hickson Compact Group 87, a diverse group of galaxies located about 400 million light-years from Earth, was acquired with the Gemini Multi-Object Spectrograph (GMOS) on the 8-meter Gemini South Telescope without the help of adaptive optics. NOAO provided the highly capable detector subsystem and related software for GMOS-South.

24 Junio 2003: A sixth magnitude globular cluster in the constellation Canes Venatici, this ball of 500,000 stars is approximately 160 light years across and 100,000 light years from Earth. The image is a combination of a B-band image and a Z-band image (Z is approximately from 8500 to 9500 A) taken at the WIYN 3.5-meter telescope with the WIYN Tip-Tilt Module (WTTM).

17 Junio 2003: On the second night of its first commissioning run on the Gemini South Telescope, the facility mid-infrared imager/spectrograph T-ReCS was used to obtain an image of Mars using a spectral filter centered at a wavelength of 12.8 microns. The image was made at 7h27m UTC on 2003 June 4. Bright areas are relatively warm, and dark areas may be cooler. In the "raw" image on the left, the bright region corresponds to the sub-solar point; there is a brightness gradient roughly symmetrical about the sub-solar point, actually skewed a bit towards mid-afternoon due to thermal inertia. The middle image shows a specially processed (unsharp-mask) version of the T-ReCS data that accentuates finer details. The right image is a composite of visible data from the Mars Global Surveyor (National Geographic Society, MOLA Science Team, MSSS, JPL, NASA) taken from the Mars Now webpage and shows Mars at approximately the same orientation …

27 Mayo 2003: This star cluster in Perseus is the home of at least seven extremely large dusty disks around young stars where newborn planets could be forming. These disks were detected in infrared images using the FLAMINGOS instrument at Kitt Peak.

27 Mayo 2003: Issue #26 (June 2003) of the Gemini Newsletter has been printed and is now being shipped to all partner offices.

12 Mayo 2003: In 1943 the American astronomer Carl K. Seyfert reported that a small percentage of galaxies have very bright nuclei that are the source of broad optical emission lines seen in their spectra. Nearly stellar in appearance, these nuclei are responsible for the emission of strong lines produced by atoms in a wide range of ionization stages. Today these objects are known as Seyfert Galaxies and the spiral galaxy NGC 4151 is a good example of this type of object. Seyfert Galaxies belong to a broader class of objects called Active Galactic Nuclei (AGN) that are characterized by energetic emission across the entire electromagnetic spectrum, from the radio to X-rays. The power source for an AGN is thought to be a central supermassive black hole where energy is generated by matter accreting onto the black hole itself and onto its surrounding accretion disk. James Radomski of the University of Florida and …