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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 …

9 Mayo 2003: This composite picture is a seamless blend of ultra-sharp NASA Hubble Space Telescope images combined with the wide view of the Mosaic Camera on the WIYN 0.9-meter telescope at Kitt Peak National Observatory near Tucson, Arizona.

29 Abril 2003: Some highly magnetized neutron stars (magnetars) are known to periodically flare up and emit large quantities of X-rays. These bursts are thought to be caused when the solid surface of the neutron star cracks, triggering "star quakes." The energy is transferred to the magnetic field and out into the hot gas that is trapped near the magnetar. One such X-ray burst was recently observed from a type of magnetar that had not been seen to burst before, conclusively linking two types of neutron stars that had previously been thought to be different. Gemini's Near-Infrared Imager, NIRI, was trained on the magnetar 1E 2259+586 shortly after X-ray bursts were detected in June of 2002. The magnetar was observed to be more than 3 times brighter in the infrared than it is in its quiescent phase. NIRI re-imaged the magnetar a week later and confirmed that it was fading, showing that the …

17 Abril 2003: A compact spiral galaxy in the constellation Coma Berenices, this image of NGC4274 comes from the public Kitt Peak Advanced Observing Program.

15 Abril 2003: Binary stars evolve in interesting ways. The more massive star in a pair evolves faster and may explode as a supernova if its original mass is greater than about 7 times the mass of our Sun. The result is that either a neutron star or a black hole is found orbiting the lower-mass companion star - as is the case with A0620-00. This system consists of an X-ray novae star, powered by the sporadic accretion material from its companion, a K5 main-sequence star. The relative faintness of the secondary star has allowed the measurement of the radial velocity of both the accretion disk around the black hole and the companion star. The black hole mass is still not well known; the most recent estimate is 11.0+/-1.9Msun (solar mass). 2668-2678, November 2001). A more robust measure is that the mass has to be greater than 2.72+/-0.06Msun. Soft X-ray transients (SXT), also …

2 Abril 2003: Saturn's moon Titan, the second largest moon in the solar system, is surrounded by a thick atmosphere of molecular nitrogen with a few percentage points of methane. This atmosphere appears to host a variety of meteorological features that show a seasonal cycle. Titan's apparent angular diameter from Earth (~0.8 arcseconds) can be resolved from the ground only with advanced techniques like adaptive optics. The opacity of Titan's stratospheric haze decreases sharply with wavelengths across the visible into the infrared. There are narrow spectral windows in the near infrared between the methane bands through which astronomers can probe Titan's surface and lower atmosphere. Henry Roe (University of California, Berkeley) and his collaborators used adaptive optics on the Gemini North and Keck II telescopes to study the tropospheric haze and the discrete clouds of Titan, and to probe its surface (Figure 1). Their observations have revealed that the southern hemisphere shows more …

1 Abril 2003: This wide-field image of the Crescent Nebula (NGC6888) was taken at the National Science Foundation's 0.9-meter telescope on Kitt Peak with the NOAO Mosaic CCD camera.

25 Marzo 2003: Over 5 days in late February/early March, staff members completely moved into the new Gemini South Southern Base Facility in La Serena, Chile. The 15,000-plus-square-foot facility features 30 offices, a 42-seat lecture hall, 2 instrument labs, 2 conference rooms and the Gemini South sea-level control room. Approximately 40 staff members currently occupy the facility.

17 Marzo 2003: This image of M5 comes from the public Kitt Peak Advanced Observing Program.

7 Marzo 2003: Located in the constellation Coma Berenices, M100 (also known as NGC4321) is one of the brighter galaxies in the Virgo Cluster. The presence of many young stars give the arms of this spiral galaxy a blue appearance. This image was taken December 20, 2002 at the WIYN 0.9-meter telescope on Kitt Peak.

26 Febrero 2003: The Gemini Near-infrared Imager (NIRI) has been working reliably and delivering excellent images at wavelengths between 1 and 5 microns. In one NIRI program, very sharp images (0.35 arcsecs FWHM without adaptive optics correction) of 11 different sub-regions of the nearby spiral galaxy M33 were collected over a period of two nights in September 2002. The infrared NIRI images probe through the intervening dust in M33 and allow us a clear view of the many evolved giant stars in this galaxy. In the inset infrared (IR) image, 22,000 individual giant stars were detected and measured. The image on the left shows what this same field looks like at visible wavelengths with a seeing of 0.75 arcsecs (FWHM). The dust seen in the optical image all but disappears in the NIRI IR image (a composite of 1.6 and 2.1 micron images). Taking a census of the stars in other galaxies is …

17 Febrero 2003: This month’s Hubble Heritage image of the Dumbbell Nebula is superimposed onto a WIYN image of M27, highlighting the differences in the field of view of the two telescopes. The Heritage site features several other supplemental ground-based images from WIYN and the Mayall 4-meter telescope.

12 Febrero 2003: The tightest orbiting brown dwarf companion ever seen has been discovered orbiting the low mass star LHS 2397a, using adaptive optics on Gemini North. The faint companion completes its orbit around the parent star at a distance of about 3 astronomical units (AUs) every 20 years. The images above show LHS 2397a in four bandpasses. The first image on the left is an optical image in the I Band obtained with the Hubble Space Telescope (HST) on April 12, 1997. The brown dwarf is seen as the very faint object at nine o'clock and is very difficult to detect in this unenhanced image. The next three images were obtained using adaptive optics in the near infrared (J, H and K' bands) on Gemini North five years later (February 7, 2002). The Gemini images use a Fourier filter to enhance the visibility of the companion, hence the presence of the companion …

29 Enero 2003: This unusual image was created from five frames imaged with filters covering a narrow range of wavelengths. The color changes across filaments are indicative of physical changes in the bright emission nebula.

28 Enero 2003: Today, in a live videoconference connecting Hawai`i with Chile, the six teachers selected to participate in the Gemini Observatory StarTeachers Exchange Program were officially announced. During the event, the 3 teachers from each location met and shared some of their ideas for the exchange using the same advanced high-speed internet videoconferencing technology that they will use to present lessons to their students back home during the exchange. The Hawai`i teachers are scheduled to visit their colleagues in Chile for two weeks in March and the Chilean teachers will make a reciprocal visit to Hawai`i in October 2003. The three Big Island StarTeachers selected are Kristen Luning, Chairperson of the Math Department at Keaau High School; Alicia Hui, a fifth grade teacher at Haili Christian School; and Christine Copes, a math and Resource Teacher at Waiakea Elementary School. The three Chilean teachers are Carmen Luz Briones, Viviana Calderon and Jenny Opazo. …

21 Enero 2003: Violent bush fires ravaging Canberra destroyed most of the facilities at the Stromlo Observatory. Fortunately there were no additional human injuries or casualties. More details on the loss of Gemini's Near-Infrared Integral Field Spectrograph can be found at the links below. Astronomy projects in ruins as observatory obliterated Aussie Fires Destroy Mount Stromlo Observatory Australian fire felt in Hilo Gemini Near-Infrared Integral-Field Spectrograph (NIFS): Destroyed by Bushfire January 2003 Historic Australian observatory gutted The Mount Stromlo Fires: A Major Heritage Loss For Australian Astronomy Mount Stromlo Observatory Destroyed by Fire Pictures of the aftermath of the fire of Saturday, 18 January 2003, at Mount Stromlo Observatory

9 Enero 2003: Gemini South Assistant Astronomer Dr. Michael Ledlow has helped confirm the existence of a giant, subatomic particle jet streaming from a spiral galaxy similar to the Milky Way. Though long known to be associated with elliptical and merging galaxies, the discovery of such jets streaming from a spiral galaxy raises significant questions about current theories on jet production. The discovery was made possible by the combination of radio, optical and infrared observations. The findings were reported at the American Astronomical Society's meeting in Seattle. Dr. Ledlow's infrared work at Gemini South was instrumental in complementing research by the team leader, Dr. William Keel with the University of Alabama, and Dr. Frazer Owen with the National Radio Astronomy Observatory. The galaxy, known as 0313-192, first came to the attention of Dr. Owen more than 20 years ago during a galaxy survey he conducted using the Very Large Array (VLA). Gemini South's …

8 Enero 2003: Found in the harsh environment of the Carina Nebula, using the Blanco telescope.

26 Diciembre 2002: The SOAR (SOuthern Astrophysical Research) telescope dome on snow covered Cerro Pachon.

18 Diciembre 2002: The Gemini Multi-Object Spectrograph (GMOS) at Gemini South Gemini South took delivery of GMOS-S in November 2002 and is preparing to install it on the telescope for commissioning very early in 2003. It is anticipated that GMOS-S will be available during semester 2003B in both imaging and several spectroscopic modes. Like its twin that began observations in 2001 on Gemini North, GMOS-S was built as a collaboration between Canada (HIA), and the UK (Astronomical Technology Centre at ROE and University of Durham). The GMOS detector system was provided by the US (National Optical Astronomy Observatory). The two GMOSs are the primary instruments for optical (0.36-1.10 µm) slit/multi-slit/integral field spectroscopy as well as imaging (5.5 arcmin field of view) on the Gemini telescopes. Michelle at Gemini North The facility mid-infrared imager and spectrometer Michelle arrived at Gemini North in the first week of December, however, Michelle did not arrive from the …