Announcements 2006

28 Diciembre 2006: About 27 nights of observing time on the SOAR 4.1-meter telescope in Chile are expected to be available to the U.S. community in 2007B through the NOAO observing time allocation process.

21 Diciembre 2006: Happy Holidays from the National Optical Astronomy Observatory.

19 Diciembre 2006: A new series of images are now available that provide a "wide-eyed" view of the Gemini North telescope. The images were obtained as part of a program to capture a time-lapse sequence of the Gemini telescopes in operation during the course of one night. Each image shows a complete 180-degree view illuminated by moonlight (except for exterior views). All images were obtained using a circular format fisheye lens and ~50 second exposures to simulate the naked-eye view of the telescope at night.

15 Diciembre 2006: A team of US astronomers led by Sebastian Daemgen (University of Arizona) has just released the results of a search for low-mass brown dwarf or planetary companions around young early-type M dwarf stars within 20 parsecs of the Sun. The 41 stars in the survey have age estimates of < 300 million years, comparable to that of the Pleiades. Within the sample 13 objects are found to host fairly bright companions, eight of these (seven binaries and one triplet) are new discoveries (Figure 1). Understanding binarity or multiplicity rates in low-mass stellar systems could provide important clues on the formation of low-mass objects including planetary systems and their population of planets. The survey was conducted using The Gemini North adaptive optics system ALTAIR in its natural guide star (NGS) mode. The strategy of the survey was to target young stars in order to increase the probability of finding intrinsically faint …

12 Diciembre 2006: A British team led by Matt Burleigh (University of Leicester) and P. F. L. Maxted (Keele University) have discovered and characterized an extremely rare stellar system composed of a white dwarf and brown dwarf pair. Named WD 0137-349, this pairing is the only known close, detached binary system with a white dwarf and a confirmed substellar companion. The system is exceptionally intriguing given the measured orbital period of P = 116 minutes. Such a short period implies that the stars orbit within one solar radius from one another. This is close enough that the brown dwarf must have survived the period of common envelope evolution where it was completely engulfed by the atmosphere of the red giant progenitor of the white dwarf. Earlier work by Maxted et al. had already established a mass of 0.39 +/- 0.035 Msun for the white dwarf and of 0.053 +/- 0.006 Msun for the …

4 Diciembre 2006: includes articles on the NSF Senior Review report and our response, Gemini science in the mid infrared, new partnerships at CTIO, first light for the QUOTA imager at WIYN, and more.

16 Noviembre 2006: Astronomers have identified 20 new stellar systems in our local solar neighborhood, including the twenty-third and twenty-fourth closest stars to the Sun. When added to eight other systems announced by this team and six by other groups since 2000, the known population of the Milky Way galaxy within 33 light-years (10 parsecs) of Earth has grown by 16 percent in just the past six years. Data taken with the SMARTS telescopes at CTIO. NOAO Press Release 06-14

13 Noviembre 2006:

9 Noviembre 2006: The cover of the FY 2006 NOAO Annual Report [1.7 MB pdf] (login required) features this image of M83, taken by the SINGG Survey Team. The report details scientific research, observatory developments, new programs, and educational/public outreach activities for the fiscal year ending September 30, 2006. A pdf of the appendices is also available [957 KB].

6 Noviembre 2006: On November 8, 2006, starting at 12:12 p.m. local MST in Tucson, Arizona, the planet Mercury began its transit across the face of the Sun, as seen from Earth. The National Science Foundation’s Kitt Peak National Observatory and the Exploratorium joined forces to present a live view of the 5 hour transit both on the mountain and via webcast.

31 Octubre 2006: Robert A. Simcoe of the MIT-Kavli Center for Astrophysics and Space Research has found new evidence of intensive heavy-element enrichment in intergalactic gas, occurring less than 1 billion years (Gyr) after the Big Bang. His discovery of a high concentration of carbon atoms in the spectra of two very distant quasars implies that vigorous star formation was already underway in some neighborhoods when the universe was only 7% of its present age. Charting the evolution of the carbon abundance is like taking a core sample of the early universe's stellar content. Since carbon nuclei are created through fusion in stellar cores, one would expect their abundance to decline at early times, approaching the formation epoch of the first stars. Simcoe's new observations show that the level of triply ionized carbon (i.e. carbon which has been stripped of three electrons, usually denoted as C IV) remains surprisingly constant as far as …

31 Octubre 2006: NOAO Astronomer Emeritus Michael Belton is a member of the science teams for two new NASA Discovery Program mission studies - one proposal would send the Deep Impact spacecraft onward to Comet Boethin in December 2008; the other would send the Stardust spacecraft to Comet Tempel 1 to observe the crater left there by Deep Impact's explosive earlier visit in 2005, which was observed widely from Kitt Peak, SOAR and Gemini North (see image).

30 Octubre 2006: An international team of researchers used Gemini mid-infrared images to investigate a sample of nearby Luminous InfraRed Galaxies (LIRGs) which are analogous to those LIRGs which are major contributors to the obscured star formation rate (SFR) density at redshift z=1, when the universe was half of its present age. The data were obtained with the mid-infrared imager/spectrograph T-ReCS on Gemini South. In Figure 1 the diffraction-limited images reveal that at high-spatial resolution, approximately 0.3 arcsecond at the observed wavelengths of 8 and 10 microns, the morphology of the mid-infrared emission in the nuclear regions of these galaxies is strikingly similar to that of the ionized gas (Paschen-alpha) revealed by Hubble Space Telescope (HST) NICMOS observations at near-infrared wavelengths. The observed mid-infrared emission of these LIRGs generally consists of bright nuclear emission, multiple circumnuclear and/or extranuclear H II regions, and diffuse emission. The stellar emission, traced by the NICMOS near-infrared continuum …

19 Octubre 2006: The NOAO Hands-On Optics team has established ongoing programs at the Boys & Girls Clubs of South Tucson and Sells (photo). For more, see the the Public Affairs and Educational Outreach section [721 KB pdf] of the September 2006 Newsletter.

16 Octubre 2006: Hawai'i Earthquake Update for Gemini North(as of 5:00 PM HST, Thursday, November 9, 2006) A fairly serious earthquake happened Sunday morning near Waikoloa, on the west side of the Big Island. At magnitude 6.6 this was a much stronger earthquake than we are accustomed to here in Hawai'i. Shortly after the event Gemini had staff on the summit to assess the damage to the telescope. We will provide updates as they warrant and information becomes available. The following item was updated at 5h00 pm HST on Thursday, November 9th Repairs to the Gemini North Secondary System have been successfully completed! The system was thoroughly tested in the lab and will be reattached to the top end of the telescope on Friday November 10th. The first half of Friday night is currently scheduled for engineering tests and, if these are successful, the telescope will be handed over for instrument tests. In …

13 Octubre 2006: Using the near infrared integral field spectrograph CIRPASS at Gemini South, Ruben Diaz and an international team of astronomers, have discovered a previously unknown hidden mass concentration that looks like a second nucleus in the starburst galaxy M83. The mass concentration is located at the youngest end of a giant star forming arc near the galaxy's center (geminiann06019a). This concentration probably represents the wreckage of the nucleus of the smaller galaxy which is being "swallowed" by M83. This double nucleus arrangement is also associated with complex kinematics near the galaxy center (geminiann06019b). The masses of the objects were derived from the kinematics of the ionized gas. The nucleus of the intruder body has an estimated mass of about 16 million times the mass of the Sun, compared to 2 million solar masses for the optical "main" nucleus. The two nuclei are about 100 parsecs apart and are probably harboring black …

13 Octubre 2006: The 3rd Community Workshop on the Ground Based O/IR System takes place November 16-17 at the Scottsdale Plaza Resort.

29 Septiembre 2006: On 2005 December 21.0773 UT, the space-based Swift Gamma Ray Burst Explorer (Burst Alert Telescope) detected a classical short gamma ray burst. The total duration of this event (named GRB 051221a) was about 1.4 seconds. Alicia M. Soderberg (CALTECH) and her collaborators have studied the burst and its afterglow in great detail using several datasets provided by space observations, radio observations with the VLA and optical observations with Gemini. They derived a detailed set of physical parameters for this burst and their analysis helps to better understand the nature of the progenitor of short bursts and their host environments. The Gemini North Telescope staff was alerted and began observations about 2.8 hours after the burst using the Gemini Multi-Object Spectrograph (GMOS). It detected a bright optical source (Figure 1), and the evolution of this afterglow was followed over several days (Figure 2). The optical source detected by GMOS corresponds to …

28 Septiembre 2006: This image of spiral galaxy NGC 253 was taken with the National Science Foundation’s Blanco 4-meter telescope at Cerro Tololo Inter-American Observatory in Chile.

20 Septiembre 2006: A GNIRS (Gemini South) study identifies a surprising class of distant massive galaxies with strongly suppressed star formation. An international team led by Mariska Kriek of Leiden Observatory (Holland) and Yale University has found that 45% of a small sample (20) of massive high-redshift galaxies exhibit very low or no star formation activity. The existence of "red and dead" massive galaxies at a time when the universe was between 1/4 to a 1/3 of its current age is surprising. During the past few years our knowledge of galaxy formation evolution has grown significantly. Several recent papers indicate that most of the stars in high-mass galaxies were formed at a higher redshift (earlier in the history of the universe) than those of low mass galaxies. This newly published work puts a new twist on the growing evidence that most massive galaxies formed at an extremely early epoch in the universe. Kriek's …