|
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Huygens Landing Site
| Description |
Huygens landing site |
| Full Description |
This image provides a comparison between the Huygens landing site on Titan as viewed by the Cassini Imaging Science Subsystem (ISS) and the NACO/SDI instrument mounted on the 8-meter Yepun telescope of the VLT (Very Large Telescope) station, in Chile. From the two images it is possible to see a high consistency between the two measurements. The Cassini image - taken in the near-infrared (938 nanometers)- shows the Huygens landing site map wrapped around Titan, rotated to the same position as the January 2005 NACO/SDI observations. The colored lines outline the regions that were imaged by Cassini at different resolutions. The lower-resolution imaging sequences are outlined in blue. Other areas have been specifically targeted to build moderate and high-resolution mosaics of surface features. These include the site where the Huygens probe has touched down on Jan. 14, 2005 (marked with the yellow X), and located at a latitude of 10.3° south and a longitude of 192.32° west (or 167.7° east). The landing site is located on the boundary between the bright region called Adiri and the dark one called Shangri-la. The red color on the NACO/SDI image corresponds to an atmospheric filter at 1.625 micron, while the blue color corresponds to a filter for the surface at 1.600 and 1.575 micron. *Credits:* NASA/JPL/Cassini-ISS/Space Science Institute and ESO/NACO-SDI/VLT |
| Date |
March 5, 2007 |
|
Titan in Detail
| title |
Titan in Detail |
| description |
New images of unsurpassed clarity have been obtained with the ESO Very Large Telescope (VLT) of formations on the surface of Titan, the largest moon in the Saturnian system. They were made by an international research team [1] during recent commissioning observations with the "Simultaneous Differential Imager (SDI)", a novel optical device, just installed at the NACO Adaptive Optics instrument. The images show a number of surface regions with very different reflectivity. Of particular interest are several large "dark" areas of uniformly low reflectivity. One possible interpretation is that they represent huge surface reservoirs of liquid hydrocarbons. These views of Titan, obtained on six nights in February 2004. At the right, the image from the first night (Feburary 1-2, 2004) has been enlarged for clarity and the coordinate grid on Titan is indicated. The images are false-colour renderings with the three SDI wavebands as red (1.575 ?m, surface), green (1.600 ?m, surface) and blue (1.625 ?m, atmosphere), respectively. *Image Credit*: European Southern Observatory |
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VLT Optical & Near-Infrared
…
| Name |
VLT Optical & Near-Infrared Image of RDCS 1252.9-2927 |
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Chandra & VLT Image of M83
| Name |
Chandra & VLT Image of M83 |
|
Hubble Sees Star Cluster "In
…
| Title |
Hubble Sees Star Cluster "Infant Mortality |
| General Information |
What is an American Astronomical Society Meeting release? A major news announcement issued at an American Astronomical Society meeting, the premier astronomy conference. Astronomers using NASA's Hubble Space Telescope have found that young stellar nurseries, called open star clusters, have very short lives. This is gleaned from new observations by Hubble's Advanced Camera for Surveys that were used to do a "Where's Waldo" search for blue stars tossed out of their open cluster "nest" in the nearby galaxy known as NGC 1313. Read more: * The Full Story [ http://hubblesite.org/newscenter/archive/releases/2007/05/full/ ] |
|
Hubble Sees Star Cluster "In
…
| Title |
Hubble Sees Star Cluster "Infant Mortality |
| General Information |
What is an American Astronomical Society Meeting release? A major news announcement issued at an American Astronomical Society meeting, the premier astronomy conference. Astronomers using NASA's Hubble Space Telescope have found that young stellar nurseries, called open star clusters, have very short lives. This is gleaned from new observations by Hubble's Advanced Camera for Surveys that were used to do a "Where's Waldo" search for blue stars tossed out of their open cluster "nest" in the nearby galaxy known as NGC 1313. Read more: * The Full Story [ http://hubblesite.org/newscenter/archive/releases/2007/05/full/ ] |
|
The Carina Nebula: Star Birt
…
| Title |
The Carina Nebula: Star Birth in the Extreme |
| General Information |
What is Hubble Heritage? A monthly showcase of new and archival Hubble images. Go to the Heritage site. In celebration of the 17th anniversary of the launch and deployment of NASA's Hubble Space Telescope, a team of astronomers is releasing one of the largest panoramic images ever taken with Hubble's cameras. READ: Junior version of this article Amazing Space Learn about this story in the Star Witness, a science newspaper available on our sister site, Amazing Space. [ http://amazing-space.stsci.edu/news/archive/2007/02/ ] It is a 50-light-year-wide view of the central region of the Carina Nebula where a maelstrom of star birth —, and death —, is taking place. This image is a mosaic of the Carina Nebula assembled from 48 frames taken with Hubble's Advanced Camera for Surveys. The Hubble images were taken in the light of neutral hydrogen during March and July 2005. Color information was added with data taken in December 2001 and March 2003 at the Cerro Tololo Inter-American Observatory in Chile. Red corresponds to sulfur, green to hydrogen, and blue to oxygen emission. |
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Black Hole in Search of a Ho
…
| Title |
Black Hole in Search of a Home |
| General Information |
What is a News Nugget? News Nuggets are bulletins from the world of astronomy. A team of European astronomers has used two of the most powerful astronomical facilities available, NASA's Hubble Space Telescope and the European Southern Observatory's (ESO) Very Large Telescope (VLT) at Cerro Paranal, to find a bright quasar without a massive host galaxy. Quasars are powerful and typically very distant sources of prodigious amounts of radiation. They are commonly associated with galaxies containing an active central black hole. The team confidently concludes that the quasar on the left, HE0450-2958 (in the center, distance about 5 billion light-years) does not have a massive host galaxy. The quasar HE1239-2426 to the right (at a distance of 1.5 billion light-years), has a normal host galaxy which displays large spiral arms. Read more: * Release Text [ http://hubblesite.org/newscenter/archive/releases/2005/13/text/ ] |
|
Black Hole in Search of a Ho
…
| Title |
Black Hole in Search of a Home |
| General Information |
What is a News Nugget? News Nuggets are bulletins from the world of astronomy. A team of European astronomers has used two of the most powerful astronomical facilities available, NASA's Hubble Space Telescope and the European Southern Observatory's (ESO) Very Large Telescope (VLT) at Cerro Paranal, to find a bright quasar without a massive host galaxy. Quasars are powerful and typically very distant sources of prodigious amounts of radiation. They are commonly associated with galaxies containing an active central black hole. The team confidently concludes that the quasar on the left, HE0450-2958 (in the center, distance about 5 billion light-years) does not have a massive host galaxy. The quasar HE1239-2426 to the right (at a distance of 1.5 billion light-years), has a normal host galaxy which displays large spiral arms. Read more: * Release Text [ http://hubblesite.org/newscenter/archive/releases/2005/13/text/ ] |
|
Spiral Galaxy In Centaurus
| Title |
Spiral Galaxy In Centaurus |
| Explanation |
Centaurus [ http://www.astro.wisc.edu/~dolan/constellations/ constellations/Centaurus.html ], the Centaur, is one of the most striking constellations [ http://www.astro.wisc.edu/~dolan/constellations/extra/ Centaurus.html ] in the southern sky. The lovely Milky Way [ http://antwrp.gsfc.nasa.gov/apod/ap990224.html ] flows through this large constellation whose celestial wonders also include the closest star to the sun, Alpha Centauri [ http://antwrp.gsfc.nasa.gov/apod/ap960526.html ], the largest globular star cluster in our galaxy, Omega Centauri [ http://antwrp.gsfc.nasa.gov/apod/ap960221.html ], and the closest active galaxy, Centaurus A [ http://antwrp.gsfc.nasa.gov/apod/ap990822.html ]. Embraced by tightly wound spiral arms of bright blue star clusters, this gorgeous galaxy - cataloged as ESO 269-57 - also falls within Centaurus' borders [ http://www.e-z.net/~haworth/constel/constel/centaurus.html ]. Seen behind a veil of foreground stars which lie within our own galaxy, this face-on spiral galaxy [ http://antwrp.gsfc.nasa.gov/apod/ap980314.html ] is about 150 million light-years away and 200,000 light-years across. The brighter foreground stars are marked by diffraction spikes [ http://antwrp.gsfc.nasa.gov/apod/ap971119.html ] caused by the telescope and yellow vertical stripes due to saturated digital camera pixels in the above Very Large Telescope image [ http://www.eso.org/outreach/press-rel/pr-1999/phot-20-99.html ] from the European Southern Observatory. Tantalizing wisps of more distant, faint galaxies are visible in the background. |
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Crumbling Comet Schwassmann-
…
| Title |
Crumbling Comet Schwassmann-Wachmann 3 Approaches |
| Explanation |
A crumbling comet will soon pass near the Earth. Comet 73P/Schwassmann-Wachmann 3 [ http://science.nasa.gov/headlines/y2006/24mar_73p.htm ] is brightening and may even be visible to the unaided eye [ http://webvision.med.utah.edu/anatomy.html ] when the fragmented comet [ http://antwrp.gsfc.nasa.gov/apod/ap040724.html ] zooms past Earth during the middle of next month. Still, the small comet poses no Earth hazard [ http://liftoff.msfc.nasa.gov/Academy/SPACE/SolarSystem/Meteors/ImpactHazard.html ], since it will pass the Earth at about 25 times the distance of the Moon. Exactly how bright Comet Schwassman-Wachmann 3 [ http://en.wikipedia.org/wiki/73P/Schwassmann-Wachmann ] will get is unknown. It is even possible, althought unlikely, that debris from the comet [ http://cometography.com/pcomets/073p.html ] will have spread out enough to cause a notable meteor shower [ http://antwrp.gsfc.nasa.gov/apod/ap031116.html ]. Pictured above [ http://www.eso.org/outreach/press-rel/pr-2006/phot-15-06.html ], Fragment B of Comet Schwassman-Wachmann 3 [ http://www.eso.org/outreach/press-rel/pr-2006/pr-15-06.html ] was photographed two nights ago by a 8.2-meter Very Large Telescope [ http://antwrp.gsfc.nasa.gov/apod/ap990309.html ] in Chile [ http://en.wikipedia.org/wiki/Chile ]. Visible [ http://antwrp.gsfc.nasa.gov/apod/ap060426.html http://www.space.com/spacewatch/060414_night_sky.html ] to the lower right of the large B fragment are many mini-comets that have broken off and now orbit the Sun separately. Each mini-comet itself sheds gas and dust and so appears to have its own hazy coma. The comet [ http://skyandtelescope.com/observing/objects/comets/article_1704_1.asp ] will pass closest to the Sun on June 7. |
|
Sirius, Sun, Moon, and South
…
| Title |
Sirius, Sun, Moon, and Southern Cross |
| Explanation |
From left to right are the enclosures of Yepun ("ye-poon", Sirius [ http://antwrp.gsfc.nasa.gov/apod/ap000611.html ]), Antu ("an-too", Sun [ http://antwrp.gsfc.nasa.gov/apod/ap000621.html ]), Kueyen ("qua-yen", Moon [ http://antwrp.gsfc.nasa.gov/apod/ap991222.html ]), and Melipal ("me-li-pal", Southern Cross [ http://antwrp.gsfc.nasa.gov/apod/ap000618.html ]), pictured here as night falls at Paranal Observatory [ http://www.eso.org/outreach/press-rel/pr-2000/ phot-15B-00.html ] in northern Chile. These are the four 8.2 meter wide telescope units of the European Southern Observatory's Very Large Telescope [ http://www.eso.org/outreach/press-rel/pr-2000/ phot-15-00.html ] (VLT). ESO astronomers and engineers plan to combine the light [ http://www.eso.org/projects/vlt/ ] of the individual units, achieving an equivalent aperture [ http://www.seds.org/billa/bigeyes.html ] of 16.4 meters which will, for a while [ http://nastol.astro.lu.se/~torben/50m/50m.html ], constitue the biggest [ http://www.sciam.com/specialissues/1299engineering/ 1299musserbox2.html ] telescope on planet Earth [ http://www.sciam.com/specialissues/1299engineering/ 1299musser.html ]. Of course, the individual telescopes also function independently. Antu, Kueyen, and Melipal have already achieved first light with Yepun expected to operate in 2001. The telescope names [ http://www.eso.org/outreach/info-events/ut1fl/names.html ] come from the Mapuche [ http://www.uchile.cl/cultura/mapa/ artesamapuche/ingles/index.htm ] language [ http://www-linguistics.stanford.edu/~arnold/mapuche/ mapudungun.html ]. They were unanimously chosen based on the winning "name-the-telescopes" essay by 17-year old Jorssy Albanez Castilla from Chuquicamata near the city of Calama. |
|
Yepun
| Title |
Yepun |
| Explanation |
Pictured above on September 3rd, the enclosure for the 8.2 meter telescope christened Yepun glints dramatically in the light of the setting sun. Later that evening, under dark skies [ http://www.eso.org/outreach/press-rel/pr-2000/ phot-15B-00.html ] at Paranal Observatory, Chile [ http://www.ociw.edu/lco/links/astro_link_en.html ], astronomers and engineers successfully captured Yepun's first light images [ http://www.eso.org/outreach/press-rel/pr-2000/ pr-18-00.html ], making Yepun the fourth and final unit of the European Southern Observatory's Very Large Telescope (VLT) array to reach this milestone. Ultimately, the light from the three other 8.2 meter unit telescopes (Antu, Kueyen, and Melipal [ http://antwrp.gsfc.nasa.gov/apod/ap000707.html ]) will be combined with Yepun's to achieve an effective aperture [ http://www.seds.org/billa/bigeyes.html ] of 16.4 meters -- creating the world's largest [ http://www.howstuffworks.com/news-item214.htm ] optical telescope [ http://www.telescope.org/rti/index.html ]. But the next major step will be to combine beams from two of the telescopes creating an interferometer. The upper part of the mostly subterranean interferometer lab is the building in front of the telescope enclosure. The VLT unit telescope names have been taken from the Mapuche [ http://www.uchile.cl/cultura/mapa/artesamapuche/ingles/ index.htm ] language [ http://www-linguistics.stanford.edu/~arnold/mapuche/ mapudungun.html ]. Originally thought to refer to the bright star Sirius, the word Yepun [ http://www.eso.org/outreach/info-events/ut1fl/yepun.html ] is now believed by linguists to mean Venus or evening star [ http://antwrp.gsfc.nasa.gov/apod/ap990903.html ]. |
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The Milky Way Over Paranal
| Title |
The Milky Way Over Paranal |
| Explanation |
It's not the sky that's falling. More accurately, the Earth is rising. The Earth's rotation [ http://video.google.com/videoplay?docid=-5041127474937930014 ] gives a continually changing view to all Earth observers, including those measuring the universe at the Paranal Observatory [ http://www.eso.org/paranal/ ]. The observatory's four, massive 8.2 meter telescope units are situated on top of the 2,600 meter high mountain, Cerro Paranal [ http://www.eso.org/paranal/site/paranal.html ], in the dry Atacama Desert in northern Chile. The individual unit telescopes [ http://antwrp.gsfc.nasa.gov/apod/ap050817.html ] can be used separately or in combination. Their names [ http://antwrp.gsfc.nasa.gov/apod/ap000707.html ], Antu, Kueyen, Melipal, and Yepun [ http://antwrp.gsfc.nasa.gov/apod/ap000927.html ], are taken from the Mapuche [ http://en.wikipedia.org/wiki/Mapuche ] language. Fittingly they translate to Sun, Moon, Evening Star, and Southern Cross [ http://antwrp.gsfc.nasa.gov/apod/ap040708.html ]. Together they are fittingly known as the European Southern Observatory [ http://www.eso.org/about-eso/ ]'s Very Large Telescope [ http://www.eso.org/projects/vlt/ ]. A higher time resolution version of the above movie is available here [ http://www.astrosurf.com/sguisard/SGU-Paranal-Voie-lactee-V4-720x576-mus-ok-en.avi ]. |
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The Orion Nebula from VLT
| Title |
The Orion Nebula from VLT |
| Explanation |
The Great Nebula in Orion is a colorful place. Visible to the unaided eye, it appears as a small fuzzy patch [ http://antwrp.gsfc.nasa.gov/apod/ap970825.html ] in the constellation of Orion [ http://www.astro.wisc.edu/~dolan/constellations/ constellations/Orion.html ]. But this image [ http://www.eso.org/outreach/press-rel/pr-2001/phot-03-01.html ], a representative-color composite of 81 near-infrared light [ http://www.ipac.caltech.edu/Outreach/Edu/infrared.html ] images taken with VLT's ISAAC [ http://www.eso.org/instruments/isaac/ ], shows the Orion Nebula [ http://www-astronomy.mps.ohio-state.edu/~ryden/ast162_3/notes14.html ] to be a busy neighborhood of young stars, hot gas, and dark dust. The power behind much of the Orion Nebula [ http://www.seds.org/billa/twn/n1976x.html ] (M42) is the Trapezium [ http://antwrp.gsfc.nasa.gov/apod/ap971118.html ] - four of the brightest stars in the nebula. The eerie blue glow surrounding the bright stars pictured here is their own starlight reflected [ http://antwrp.gsfc.nasa.gov/apod/ap990829.html ] by nearby dust [ http://antwrp.gsfc.nasa.gov/apod/ap990509.html ]. Dark brown dust filaments [ http://antwrp.gsfc.nasa.gov/apod/ap980318.html ] cover much of the region [ http://antwrp.gsfc.nasa.gov/apod/ap980612.html ]. The whole Orion Nebula [ http://antwrp.gsfc.nasa.gov/apod/ap971201.html ] cloud complex, which includes [ http://antwrp.gsfc.nasa.gov/apod/ap990103.html ] the Horsehead Nebula [ http://antwrp.gsfc.nasa.gov/apod/ap000827.html ], will slowly disperse over the next 100,000 years. |
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Another Comet LINEAR Breaks
…
| Title |
Another Comet LINEAR Breaks Up |
| Explanation |
Last year, a "different" comet LINEAR (C/1999 S4) [ http://antwrp.gsfc.nasa.gov/cgi-bin/apod/apod_search?LINEAR+S4 ] broke up. This year, a comet first imaged [ http://cfa-www.harvard.edu/iauc/07500/07564.html ] by the Lincoln Near Asteroid Research [ http://www.ll.mit.edu/LINEAR/ ] (LINEAR) telescope in New Mexico [ http://www.state.nm.us/ ] on 2001 January 3, is also breaking up. This new Comet LINEAR (C/2001 A2) [ http://encke.jpl.nasa.gov/whats_visible.html#2001A2 ] unexpectedly brightened to the edge of naked-eye visiblilty a few weeks ago when its nucleus broke in two. Observations taken just last week [ http://www.eso.org/outreach/press-rel/pr-2001/phot-18-01.html ] now indicate that one of the two remaining nuclear fragments [ http://meteors.com/cometlinear/ ] has again fragmented. The first piece to break off is visible on the upper left of the above false-color image [ http://www.eso.org/outreach/press-rel/pr-2001/phot-18-01.html ] by a Very Large Telescope [ http://antwrp.gsfc.nasa.gov/apod/ap000707.html ], while additional fragmentation is inferred from the brightness and elongation of the spot on the lower right. When a comet nucleus [ http://antwrp.gsfc.nasa.gov/apod/ap000805.html ] splits, new surfaces are exposed and previously trapped ice and gas are released that evaporate and brighten in the energetic sunlight. Comet LINEAR may remain visible with little or no optical aid into early June [ http://www.skypub.com/sights/skyevents/0105skyevents.shtml ]. In contrast, at least two other much dimmer Comet [ http://encke.jpl.nasa.gov/whats_visible.html#1999T2 ] LINEARs [ http://encke.jpl.nasa.gov/whats_visible.html#1999Y1 ] discovered recently appear stable. |
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A Laser Strike at the Galact
…
| Title |
A Laser Strike at the Galactic Center |
| Explanation |
Why are these people shooting a powerful laser into the center of our Galaxy? Fortunately, this is not meant to be the first step in a Galactic war [ http://en.wikipedia.org/wiki/Babylon_5 ]. Rather, astronomers at the Very Large Telescope [ http://antwrp.gsfc.nasa.gov/apod/ap000707.html ] (VLT) site in Chile [ http://en.wikipedia.org/wiki/Chile ] are trying to measure the distortions of Earth's ever changing atmosphere [ http://antwrp.gsfc.nasa.gov/apod/ap000725.html ]. Constant imaging of high-altitude atoms excited by the laser -- which appear like an artificial star [ http://antwrp.gsfc.nasa.gov/apod/ap050207.html ] -- allow astronomers to instantly measure atmospheric blurring [ http://www2.keck.hawaii.edu/optics/lgsao/lgsbasics.html ]. This information is fed back to a VLT telescope mirror which is then slightly deformed [ http://www.eso.org/projects/aot/introduction.html ] to minimize this blurring. In this case, a VLT was observing our Galaxy's center [ http://www.astro.ucla.edu/~tanner/gcintro.html ], and so Earth's atmospheric blurring in that direction was needed. As for inter-galaxy warfare [ http://en.wikipedia.org/wiki/Star_wars ], when viewed from our Galaxy's center [ http://antwrp.gsfc.nasa.gov/apod/ap050403.html ], no casualties are expected. In fact, the light from this powerful laser [ http://www.eso.org/public/outreach/press-rel/pr-2007/pr-27-07.html ] would combine with light from our Sun to together appear only as bright [ http://www.oreilly.com/catalog/alien/chapter/ch07.html ] as a faint and distant star. |
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The Sombrero Galaxy from VLT
| Title |
The Sombrero Galaxy from VLT |
| Explanation |
Why does the Sombrero Galaxy look like a hat? Reasons include the Sombrero [ http://www.seds.org/messier/m/m104.html ]'s unusually large and extended central bulge of stars, and dark prominent dust [ http://antwrp.gsfc.nasa.gov/apod/ap990509.html ] lanes that appear in a disk that we see nearly edge-on [ http://antwrp.gsfc.nasa.gov/apod/ap981220.html ]. Billions of old stars [ http://antwrp.gsfc.nasa.gov/apod/ap991103.html ] cause the diffuse glow of the extended central bulge. Close inspection of the bulge in the above photograph [ http://www.eso.org/outreach/press-rel/pr-2000/phot-07-00.html ] shows many points of light that are actually globular clusters [ http://antwrp.gsfc.nasa.gov/apod/globular_clusters.html ]. M104's spectacular dust rings harbor many younger and brighter stars, and show intricate details astronomers don't yet fully understand [ http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=1995A%26A...303..673E ]. The very center of the Sombrero [ http://antwrp.gsfc.nasa.gov/apod/ap951109.html ] glows across the electromagnetic spectrum [ http://imagine.gsfc.nasa.gov/docs/science/know_l1/emspectrum.html ], and is thought to house a large black hole [ http://image.gsfc.nasa.gov/poetry/ask/abholes.html ]. Fifty million-year-old light from the Sombrero Galaxy [ http://www.hawastsoc.org/messier/fslide121.html ] can be seen with a small telescope [ http://antwrp.gsfc.nasa.gov/apod/ap011014.html ] towards the constellation [ http://www.astro.wisc.edu/~dolan/constellations/extra/constellations.html ] of Virgo [ http://www.astro.wisc.edu/~dolan/constellations/constellations/Virgo.html ]. |
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Breaking Distant Light
| Title |
Breaking Distant Light |
| Explanation |
In the distant universe, time [ http://physics.nist.gov/GenInt/Time/time.html ] appears to run slow. Since time-dilated [ http://www.fourmilab.ch/cship/timedial.html ] light appears shifted toward the red end of the spectrum [ http://www.lbl.gov/MicroWorlds/ALSTool/EMSpec/EMSpec2.html ] (redshifted), astronomers are able to use cosmological time-slowing [ http://itss.raytheon.com/cafe/cosm/expan.html ] to help measure vast distances [ http://antwrp.gsfc.nasa.gov/debate/debate96.html ] in the universe. Above [ http://www.eso.org/outreach/press-rel/pr-2002/pr-04-02.html ], the light from distant galaxies [ http://antwrp.gsfc.nasa.gov/apod/ap000709.html ] has been broken up into its constituent colors (spectra [ http://imagine.gsfc.nasa.gov/YBA/M31-velocity/galactic_redshift-2.html ]), allowing astronomers to measure the redshift [ http://www.astro.virginia.edu/~jh8h/glossary/redshift.htm ] of known spectral lines [ http://imagine.gsfc.nasa.gov/docs/science/how_l1/spectral_what.html ]. The novelty of the above image [ http://www.eso.org/outreach/press-rel/pr-2002/pr-04-02.html ] is that the distance to hundreds of galaxies [ http://antwrp.gsfc.nasa.gov/apod/ap010904.html ] can now be measured on a single frame using the Visible MultiObject Spectrograph [ http://www.astrsp-mrs.fr/virmos/ ] that has begun operating at the Very Large Telescope array [ http://antwrp.gsfc.nasa.gov/apod/ap000707.html ] in Chile [ http://www.cia.gov/cia/publications/factbook/geos/ci.html ]. Analyzing the space distribution of distant objects [ http://antwrp.gsfc.nasa.gov/apod/ap020117.html ] will allow insight into when and how stars, galaxies, and quasars [ http://antwrp.gsfc.nasa.gov/apod/ap020309.html ] formed, clustered, and evolved [ http://antwrp.gsfc.nasa.gov/apod/ap990905.html ] in the early universe [ http://antwrp.gsfc.nasa.gov/debate/debate98.html ]. |
|
Spiral Galaxy NGC 2997 from
…
| Title |
Spiral Galaxy NGC 2997 from VLT |
| Explanation |
NGC 2997 is a grand design spiral galaxy [ http://www.seds.org/messier/spir.html ]. Its small nucleus and sprawling spiral arms give it a type Sc [ http://zebu.uoregon.edu/~js/ast123/lectures/lec13.html ] designation. NGC 2997, pictured above [ http://www.eso.org/outreach/press-rel/pr-1999/pr-06-99.html ], is speeding away [ http://archive.ncsa.uiuc.edu/Cyberia/Cosmos/ExpandUni.html ] from us at about 1100 kilometers per second, which would place it at about 55 million light years [ http://chandra.harvard.edu/photo/cosmic_distance.html ] distant, given current estimates of the expansion rate [ http://csep1.phy.ornl.gov/guidry/violence/hubble_constant.html ] of our universe. NGC 2997 [ http://www.ast.cam.ac.uk/AAO/images/captions/aat017.html ] is thought to have a mass of about 100 billion times that of our Sun [ http://antwrp.gsfc.nasa.gov/apod/sun.html ], but is probably less massive than our own Milky Way galaxy [ http://casswww.ucsd.edu/public/tutorial/MW.html ]. NGC 2997 is not seen face-on [ http://antwrp.gsfc.nasa.gov/apod/ap011004.html ] - it is thought tilted by about 45 degrees. NGC 2997 is particularly notable [ http://adsbit.harvard.edu/cgi-bin/nph-iarticle_query?1989ApJ...341..722W ] for a nucleus [ http://antwrp.gsfc.nasa.gov/apod/ap020603.html ] surrounded by a chain of hot giant clouds of ionized [ http://csep10.phys.utk.edu/astr162/lect/light/ionization.html ] hydrogen [ http://pearl1.lanl.gov/periodic/elements/1.html ]. |
|
Pluto & Charon Eclipse a Tri
…
| Title |
Pluto & Charon Eclipse a Triple Star |
| Explanation |
Occasionally, a planet in our Solar System [ http://space.jpl.nasa.gov/ ] will pass in front of a bright star. Since stars and planets take up so little space on the sky, such events are quite rare. Two months ago, however, Pluto [ http://www.nineplanets.org/pluto.html ] and its large moon Charon [ http://www.nineplanets.org/pluto.html#charon ] passed in front of a comparatively bright triple star system [ http://antwrp.gsfc.nasa.gov/apod/ap991219.html ] known as P126. By noting how P126 A dimmed, the event was useful for studying Pluto's relatively unknown atmosphere [ http://www.windows.ucar.edu/tour/link=/pluto/P_atm_evolution.html ]. A Very Large Telescope [ http://antwrp.gsfc.nasa.gov/apod/ap000707.html ] in Chile [ http://www.cia.gov/cia/publications/factbook/geos/ci.html ] using a deformable mirror [ http://www.mtwilson.edu/Science/AdapOpt/Overview/ ] to counter the blurring effect [ http://antwrp.gsfc.nasa.gov/apod/ap000725.html ] of Earth's atmosphere captured the above image [ http://www.eso.org/outreach/press-rel/pr-2002/phot-21-02.html ]. |
|
BHR 71: Stars, Clouds, and J
…
| Title |
BHR 71: Stars, Clouds, and Jets |
| Explanation |
What is happening to molecular cloud [ http://antwrp.gsfc.nasa.gov/apod/ap010923.html ] BHR 71? Quite possible, a binary star [ http://antwrp.gsfc.nasa.gov/apod/ap991219.html ] system is forming inside. Most stars in our Galaxy [ http://casswww.ucsd.edu/public/tutorial/MW.html ] are part of binary star systems [ http://antwrp.gsfc.nasa.gov/apod/ap970219.html ], but few have ever been seen in formation. Recent observations [ http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=2001ApJ...554L..91B ] of dust [ http://antwrp.gsfc.nasa.gov/apod/ap010813.html ]-darkened Bok Globule [ http://antwrp.gsfc.nasa.gov/apod/ap961229.html ] BHR 71, however, show evidence for two young stars forming deep in the cloud, likely close enough to form a binary [ http://instruct1.cit.cornell.edu/courses/astro101/java/binary/binary.htm ]. Isolated BHR 71 [ http://cfa-www.harvard.edu/~bourke/bhr71.html ] spans about one light year [ http://www.howstuffworks.com/question94.htm ] and lies only about 600 light years away in the southern sky [ http://antwrp.gsfc.nasa.gov/apod/ap000618.html ]. The brighter embedded star -- not visible here -- is about 10 times as bright as the Sun [ http://www.nineplanets.org/sol.html ] and drives the jet [ http://antwrp.gsfc.nasa.gov/apod/ap000321.html ] that swept out the empty lane. The above four-color image [ http://cfa-www.harvard.edu/~bourke/papers.html ] was taken with a Very Large Telescope [ http://antwrp.gsfc.nasa.gov/apod/ap000707.html ] in Chile [ http://www.cia.gov/cia/publications/factbook/geos/ci.html ]. |
|
VLT: A New Largest Optical T
…
| Title |
VLT: A New Largest Optical Telescope |
| Explanation |
What is the largest telescope in the world? In the optical, this title [ http://www.seds.org/billa/bigeyes.html ] was long held by the Hale 200-inch [ http://astro.caltech.edu/observatories/palomar/ ], and is presently held by the Keck telescopes [ http://antwrp.gsfc.nasa.gov/apod/ap960715.html ] in Hawaii. But an even larger optical telescope is being built. Dubbed the Very Large Telescope [ http://www.eso.org/vlt/ ] (VLT), the European Southern Observatory (ESO) is building four 8.2-meter mirrors in Chile [ http://sunsite.dcc.uchile.cl/chile/chile.html ] which together will act as a single telescope with a mirror diameter of over 16-meters. The first of these telescopes should be completed [ http://www.eso.org/vlt/systeng/unitelsc/planning.htm ] in 1997, and all four should be completed and working together sometime in the year 2000. The VLT [ http://www.eso.org/vlt/systeng/unitelsc/uniteles.htm ] will use active optics [ http://www.pd.astro.it/TNG/TechRep/rep53/node4.html ] to create sub-arcsecond [ http://xalph.ast.cam.ac.uk/niel/scales1.ascii ] resolution. This, combined with the enormous light-gathering power, will allow astronomers to explore dim objects in our Galaxy [ http://antwrp.gsfc.nasa.gov/apod/ap960213.html ] and the early universe [ http://antwrp.gsfc.nasa.gov/apod/ap960628.html ]. |
|
Spiral Galaxy In Centaurus
| Title |
Spiral Galaxy In Centaurus |
| Explanation |
Centaurus [ http://www.astro.wisc.edu/~dolan/constellations/ constellations/Centaurus.html ], the Centaur, is one of the most striking constellations [ http://www.astro.wisc.edu/~dolan/constellations/extra/ Centaurus.html ] in the southern sky. The lovely Milky Way [ http://antwrp.gsfc.nasa.gov/apod/ap990224.html ] flows through this large constellation whose celestial wonders also include the closest star to the sun, Alpha Centauri [ http://antwrp.gsfc.nasa.gov/apod/ap030323.html ], the largest globular star cluster in our galaxy, Omega Centauri [ http://antwrp.gsfc.nasa.gov/apod/ap020416.html ], and the closest active galaxy, Centaurus A [ http://antwrp.gsfc.nasa.gov/apod/ap021017.html ]. Embraced by tightly wound spiral arms of bright blue star clusters, this gorgeous galaxy - cataloged as ESO 269-57 - also falls within Centaurus' borders [ http://www.e-z.net/~haworth/constel/constel/centaurus.html ]. Seen behind a veil of foreground stars which lie within our own galaxy, this face-on spiral galaxy [ http://antwrp.gsfc.nasa.gov/apod/ap980314.html ] is about 150 million light-years away and 200,000 light-years across. The brighter foreground stars are marked by diffraction spikes [ http://antwrp.gsfc.nasa.gov/apod/ap971119.html ] caused by the telescope and yellow vertical stripes due to saturated digital camera pixels in the above Very Large Telescope image [ http://www.eso.org/outreach/press-rel/pr-1999/phot-20-99.html ] from the European Southern Observatory. Tantalizing wisps of more distant, faint galaxies are visible in the background. |
|
M83: The Southern Pinwheel G
…
| Title |
M83: The Southern Pinwheel Galaxy from VLT |
| Explanation |
M83 [ http://www.seds.org/messier/m/m083.html ] is one of the closest and brightest spiral galaxies [ http://www.seds.org/messier/spir.html ] on the sky. Visible with binoculars in the constellation of Hydra [ http://www.astro.wisc.edu/~dolan/constellations/ constellations/Hydra.html ], majestic spiral arms have prompted its nickname as the Southern Pinwheel. Although discovered 250 years ago, only much later [ http://antwrp.gsfc.nasa.gov/debate/debate20.html ] was it appreciated that M83 [ http://antwrp.gsfc.nasa.gov/apod/ap990926.html ] was not a nearby gas cloud, but a barred spiral galaxy [ http://www.smv.org/hastings/bsmain.htm ] much like our own Milky Way Galaxy [ http://antwrp.gsfc.nasa.gov/apod/ap971229.html ]. M83, pictured above [ http://www.eso.org/outreach/press-rel/pr-1999/ pr-18-99.html ] in a photograph from a Very Large Telescope [ http://www.eso.org/projects/vlt/ ], is a prominent member of a group of galaxies that includes Centaurus A [ http://antwrp.gsfc.nasa.gov/apod/ap990822.html ] and NGC 5253, all of which lie about 15 million light years distant. To date, six supernova explosions [ http://antwrp.gsfc.nasa.gov/apod/ap981230.html ] have been recorded in M83. An intriguing double circumnuclear ring [ http://antwrp.gsfc.nasa.gov/apod/ap011106.html ] has been discovered at the center of M83 [ http://antwrp.gsfc.nasa.gov/apod/ap030206.html ]. |
|
The Crab Nebula from VLT
| Title |
The Crab Nebula from VLT |
| Explanation |
The Crab Nebula, filled with mysterious filaments, is the result of a star that was seen to explode in 1054 AD. This spectacular supernova [ http://imagine.gsfc.nasa.gov/docs/science/know_l1/supernovae.html ] explosion was recorded by Chinese and (quite probably) Anasazi Indian [ http://www.co.blm.gov/ahc/anasazi.htm ] astronomers. The filaments are mysterious because they appear to have less mass than expelled in the original supernova and higher speed than expected from a free explosion. In the above picture taken recently from a Very Large Telescope [ http://antwrp.gsfc.nasa.gov/apod/ap030914.html ap990309.html ], the color indicates what is happening to the electrons [ http://www-istp.gsfc.nasa.gov/Education/welect.html ] in differentparts of the Crab Nebula. Red indicates the electrons are recombining with protons to form neutral hydrogen, while blue indicates the electrons are whirling around the magnetic field of the inner nebula. In the nebula [ http://apod.gsfc.nasa.gov/cgi-bin/apod/apod_search?crab+nebula ]'s very center lies a pulsar: a neutron star rotating, in this case, 30 times a second. |
|
Redshift 10: Evidence for a
…
| Title |
Redshift 10: Evidence for a New Farthest Galaxy |
| Explanation |
What's the farthest galaxy known? The answer keeps [ http://antwrp.gsfc.nasa.gov/apod/ap040217.html ] changing [ http://antwrp.gsfc.nasa.gov/apod/ap980324.html ] as astronomers compete to find galaxies [ http://antwrp.gsfc.nasa.gov/apod/ap040309.html ] that top the list. The new claimed record [ http://www.eso.org/outreach/press-rel/pr-2004/pr-04-04.html ] holder is now the faint smudge indicated in the above images by an 8.2-meter Very Large Telescope [ http://antwrp.gsfc.nasa.gov/apod/ap000707.html ] (VLT) operating in Chile [ http://www.cia.gov/cia/publications/factbook/geos/ci.html ]. Detected light left this galaxy 13.2 billion of years ago, well before the Earth formed, when the universe was younger than 3 percent of its present age [ http://antwrp.gsfc.nasa.gov/apod/ap031231.html ]. Astronomers have estimated [ http://www.arxiv.org/abs/astro-ph/0403025 ] a redshift [ http://www.astro.virginia.edu/~jh8h/glossary/redshift.htm ] of 10 for this galaxy, the first double-digit claim for any galaxy. Young galaxies are of much interest to astronomers because many unanswered questions exist on when and how galaxies formed in the early universe. The distant redshift, if confirmed, would also give valuable information about galaxy surroundings [ http://www.arxiv.org/abs/astro-ph/0403193 ] at the end of the universe's dark age [ http://arxiv.org/abs/astro-ph/0307396 ]. Although this galaxy's distance exceeds that of even the farthest known quasar [ http://antwrp.gsfc.nasa.gov/apod/ap000419.html ], it is still in front of the pervasive glowing gas that is now seen as the cosmic microwave background radiation [ http://www.astro.ubc.ca/people/scott/faq_basic.html ]. |
|
The Spectrum of a Meteor
| Title |
The Spectrum of a Meteor |
| Explanation |
Chasing the brief flash of a meteor [ http://science.nasa.gov/headlines/y2004/ 25jun_perseids2004.htm ] trail across the sky with a very large telescope is a nearly impossible task. But on May 12, 2002, astronomers got lucky [ http://www.eso.org/outreach/press-rel/pr-2004/ pr-19-04.html ], as a bright meteor chanced across the narrow slit of their spectrograph [ http://outreach.atnf.csiro.au/education/senior/astrophysics/ spectrographs.html ] at the Paranal Observatory [ http://www.eso.org/paranal/ ]. At the time, the spectrograph was being used to study the light [ http://csep10.phys.utk.edu/astr162/lect/light/ absorption.html ] from a supernova, separating and recording the many near-infrared [ http://www.ipac.caltech.edu/Outreach/Edu/Regions/ irregions.html ] emission lines produced by atoms in the distant stellar explosion. Below this artistic montage of a meteor streak and Very Large Telescope units [ http://antwrp.gsfc.nasa.gov/apod/ap000927.html ] at Paranal, panel a shows the near-infrared sky background spectrum and the May 12 meteor combined. Panel b shows the emission spectrum of the meteor alone, after subtracting away the background contributions. The meteor emission is due to colliding oxygen and nitrogen atoms and molecules in the superheated [ http://antwrp.gsfc.nasa.gov/apod/ap011122.html ] air along the glowing trail [ http://antwrp.gsfc.nasa.gov/apod/ap030802.html ] at an altitude of about 100 kilometers. |
|
NGC 6302: The Butterfly Nebu
…
| Title |
NGC 6302: The Butterfly Nebula |
| Explanation |
The Butterfly Nebula [ http://antwrp.gsfc.nasa.gov/apod/ap971021.html ] is only thousands of years old. As a central star of a binary system [ http://antwrp.gsfc.nasa.gov/apod/ap970219.html ] aged, it threw off its outer envelopes of gas in a strong stellar wind [ http://mars-hotel.ph.msstate.edu/~mhia/data/S/Stellarwind.html ]. The remaining stellar core is so hot it ionizes the previously ejected gas, causing it to glow. The different colors of this planetary nebula [ http://www.seds.org/messier/planetar.html ] are determined by small differences in its composition. This bipolar nebula [ http://antwrp.gsfc.nasa.gov/apod/ap971223.html ] will continue to shine brightly for only a few thousand more years, after which its central star will fade and become a white dwarf [ http://antwrp.gsfc.nasa.gov/apod/ap971102.html ] star. The above picture [ http://www.hq.eso.org/outreach/info-events/ut1fl/pr-pictures/ut1fl-set3.html#04 ] is one of the first ever taken by the Very Large Telescope [ http://antwrp.gsfc.nasa.gov/apod/ap960901.html ] (VLT), a new 8.2-meter telescope located in Chile [ http://sunsite.dcc.uchile.cl/chile/chile.html ]. |
|
NGC 4650A: Strange Galaxy an
…
| Title |
NGC 4650A: Strange Galaxy and Dark Matter |
| Explanation |
This strangely distorted galaxy of stars [ http://www.eso.org/outreach/press-rel/pr-1998/phot-19-98.html ] is cataloged as NGC 4650A. It lies about 165 million light-years away in the southern constellation Centaurus [ http://www.astro.wisc.edu/~dolan/constellations/constellations/ Centaurus.html ]. The complex system seems to have at least two parts, a flattened disk of stars with a dense, bright, central core and a sparse, sharply tilted ring of gas, dust and stars [ http://antwrp.gsfc.nasa.gov/apod/ap980615.html ]. Observations show that the stars in the disk and the stars and gas in the ring really do move in two different, nearly perpendicular planes, probably as the result of a past galaxy vs. galaxy collision [ http://oposite.stsci.edu/pubinfo/pr/97/34/af3.html ]. The observed motions within both disk and ring also indicate the |
|
M27: Not A Comet
| Title |
M27: Not A Comet |
| Explanation |
While searching the skies above 18th century France for comets, astronomer Charles Messier [ http://www.seds.org/messier/xtra/history/biograph.html ] diligently recorded this object as number 27 on his list of things which are definitely not comets [ http://antwrp.gsfc.nasa.gov/apod/ap960626.html ]. So what is it? Well, 20th century astronomers would classify it as a Planetary Nebula [ http://www.seds.org/messier/planetar.html ] ... but it's not a planet either, even though it may appear round [ http://antwrp.gsfc.nasa.gov/apod/ap980518.html ] and planet-like in a small telescope. Messier 27 (M27) is now known to be an excellent example of a gaseous emission nebula [ http://www.astro.washington.edu/balick/WFPC2/ ] created as a sun-like star runs out [ http://antwrp.gsfc.nasa.gov/apod/ap980426.html ] of nuclear fuel in its core. The nebula forms as the star's outer layers are expelled into space, with a visible glow generated by atoms excited by the dying star's intense but invisible ultraviolet light [ http://imagine.gsfc.nasa.gov/docs/science/know_l1/emspectrum.html ]. Known by the popular name of the "Dumbbell Nebula" [ http://www.seds.org/messier/m/m027.html ], the beautifully symmetric interstellar gas cloud is about 1,200 light-years away in the constellation Vulpecula [ http://www.astro.wisc.edu/~dolan/constellations/ constellations/Vulpecula.html ]. This gorgeous synthetic color picture of M27 [ http://www.eso.org/outreach/press-rel/pr-1998/phot-38-98.html ] was produced during testing of the European Southern Observatory's new Very Large Telescope [ http://antwrp.gsfc.nasa.gov/apod/ap960901.html ]. |
|
Spiral Galaxy NGC 1232
| Title |
Spiral Galaxy NGC 1232 |
| Explanation |
Galaxies [ ftp://crux.astr.ua.edu/web/goodies/data_resources/galaxies.text ] are fascinating not only for what is visible, but for what is invisible. Grand spiral [ http://antwrp.gsfc.nasa.gov/apod/ap980606.html ] galaxy NGC 1232 [ http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=1997AAS...191.8203B&db_key=AST&high=34f6e1de7f27181 ], recently captured [ http://www.eso.org/outreach/press-rel/pr-1998/pr-14-98.html ] in detail by the new Very Large Telescope [ http://antwrp.gsfc.nasa.gov/apod/ap960901.html ], is a good example. The visible is dominated by millions of bright stars [ http://antwrp.gsfc.nasa.gov/apod/ap971018.html ] and dark dust [ http://antwrp.gsfc.nasa.gov/apod/ap961119.html ], caught up in a gravitational swirl of spiral arms rotating about the center. Open clusters [ http://antwrp.gsfc.nasa.gov/apod/ap980329.html ] containing bright blue stars can be seen sprinkled along these spiral arms, while dark lanes [ http://antwrp.gsfc.nasa.gov/apod/ap980116.html ] of dense interstellar dust [ http://antwrp.gsfc.nasa.gov/apod/ap980121.html ] can be seen sprinkled between them. Less visible, but detectable, are billions of dim normal stars and vast tracts of interstellar gas [ http://antwrp.gsfc.nasa.gov/apod/ap980301.html ], together wielding such high mass that they dominate the dynamics of the inner galaxy [ http://hermes.astro.washington.edu:80/scied/astro/hubble/hubble.html ]. Invisible are even greater amounts of matter in a form we don't yet know - pervasive dark matter [ http://xrtpub.harvard.edu/Xray/dark_matter.html ] needed to explain the motions [ http://www.astro.queensu.ca/~dursi/dm-tutorial/dm2.html ] of the visible in the outer galaxy. What's out there? [ http://antwrp.gsfc.nasa.gov/debate/debate98.html ] |
|
Star-Forming Region RCW38
| Title |
Star-Forming Region RCW38 |
| Explanation |
Star cluster RCW38 was hiding. This open cluster [ http://antwrp.gsfc.nasa.gov/apod/ap980329.html ] of stars is located about 5000 light years away towards the constellation of Vela [ http://www.astro.wisc.edu/~dolan/constellations/constellations/Vela.html ]. Looking there will not normally reveal most of the stars in this cluster, though. The reason is that the open cluster [ http://antwrp.gsfc.nasa.gov/apod/ap980803.html ] is so young that it is still shrouded in thick dust [ http://antwrp.gsfc.nasa.gov/apod/ap980104.html ] that absorbs visible light. This dust typically accompanies the gas that condenses to form young stars [ http://antwrp.gsfc.nasa.gov/apod/ap980412.html ]. When viewed in infrared light [ http://www.ipac.caltech.edu/Outreach/Edu/discovery.html ], however, the star cluster in RCW38 [ http://adsbit.harvard.edu/cgi-bin/nph-iarticle_query?1987MNRAS.228..721M ] is revealed, because dust is less effective at absorbing infrared light. The above photograph [ http://www.eso.org/outreach/press-rel/pr-1998/pr-19-98.html ] was one of the first ever taken with the new Infrared Spectrometer and Array Camera [ http://www.eso.org/instruments/isaac/ ] (ISAAC) affixed to the 8.2-meter Very Large Telescope [ http://antwrp.gsfc.nasa.gov/apod/ap960901.html ]. |
|
The First Image of an Extra
…
| Title |
The First Image of an Extra Solar Planet |
| Explanation |
It's the faint red object, not the bright white one that might be a historic find. The white object is surely a brown dwarf star [ http://astron.berkeley.edu/~stars/bdwarfs/ ]. Quite possibly, however, the red object is the first direct image of a planet beyond [ http://exoplanets.org/ ] our Solar System [ http://www.nineplanets.org/overview.html ]. The intriguing possibility was first reported last year, but many astronomers weren't then convinced that the "planet" was not just a background star. Earlier this year, the 2M1207 star system [ http://www.space.com/scienceastronomy/planet_photo_040910.html ] was imaged twice more in an effort to resolve the issue. To the delight of the scientific team [ http://www.arxiv.org/abs/astro-ph/0504659 ], the objects kept the same separation, indicating that they are gravitationally bound [ http://www.edu-observatory.org/eo/binary_stars.html ]. The faint red object 2M1207b is therefore 100 times fainter, intrinsically, than the bright white brown dwarf 2M1207a -- a characteristic well explained by a planet roughly five times the mass of Jupiter [ http://antwrp.gsfc.nasa.gov/apod/jupiter.html ]. The discovery [ http://www.arxiv.org/abs/astro-ph/0504659 ] - still subject to further confirmation - is considered a step toward the more ambitious goal of imaging Earth-like planets [ http://origins.stsci.edu/under/planets.shtml ] orbiting distant stars. The above image [ http://www.eso.org/outreach/press-rel/pr-2005/pr-12-05-p2.html ] was taken with the high-resolution adaptive-optic NaCo [ http://www.eso.org/instruments/naco/ ] camera attached to the 8-meter Very Large Telescope [ http://antwrp.gsfc.nasa.gov/apod/ap000707.html ] Yepun in Chile [ http://www.cia.gov/cia/publications/factbook/geos/ci.html ]. |
|
The VLT Interferometric Arra
…
| Title |
The VLT Interferometric Array |
| Explanation |
The Very Large Telescope (VLT) Interferometric Array [ http://www.eso.org/projects/vlti/ ] will be able to act as individual telescopes or as one huge telescope. Of the four planned VLTs in Chile [ http://www.eso.org/paranal/ ], two have now reached completion. The first VLT [ http://antwrp.gsfc.nasa.gov/apod/ap981009.html ] to operate is visible on the left of the above photograph [ http://www.eso.org/outreach/info-events/ut1fl/pr-pictures/ut1fl-set1.html ] and was recently given the name Antu [ http://www.eso.org/outreach/press-rel/pr-1999/pr-06-99.html ]. To its right is Kueyen, which achieved its first observations just last week. Each VLT telescope [ http://www.eso.org/outreach/info-events/ut1fl/whitebook/ ] by itself is now one of the largest optical telescopes [ http://www.seds.org/billa/bigeyes.html ] in the world, joining the new cadre of large telescopes with mirrors greater than 8-meters in diameter. After Melipal and Yepun are completed in the next few years, the four VLTs [ http://antwrp.gsfc.nasa.gov/apod/ap960901.html ] will be able to combine their light [ http://www.eso.org/outreach/info-events/ut1fl/whitebook/wb90.html#ch90 ] to achieve the sensitivity of a single 16-meter telescope, and the resolution of a single 200-meter telescope. Over the next few years, the VLT telescopes will explore the universe [ http://www.eso.org/projects/vlti/science/index.html ] in unprecedented detail, searching for everything from ordinary planets orbiting nearby stars [ http://cannon.sfsu.edu/~gmarcy/planetsearch/planetsearch.html ] to extraordinary explosions in the distant universe [ http://antwrp.gsfc.nasa.gov/apod/ap981230.html ]. |
|
NGC 2997 from VLT
| Title |
NGC 2997 from VLT |
| Explanation |
Add another 8-meter telescope to the list of modern optical telescope giants [ http://www.seds.org/billa/bigeyes.html ]. Kueyen achieved a first-light photograph of a bright star on March 1, ahead of schedule. The above picture [ http://www.eso.org/outreach/press-rel/pr-1999/pr-06-99.html ] of spiral galaxy NGC 2997 [ http://antwrp.gsfc.nasa.gov/apod/ap961030.html ] was taken with Antu [ http://www.eso.org/outreach/press-rel/pr-1999/pr-06-99.html ], the first of the four planned Very Large Telscopes [ http://antwrp.gsfc.nasa.gov/apod/ap990309.html ] (VLTs) being built in Chile [ http://www.eso.org/paranal/site/paranal.html ] for the European Southern Observatory. NGC 2997 [ http://starchild.gsfc.nasa.gov/docs/StarChild/universe_level2/ngc2997.html ] is a thin spiral galaxy [ http://www.seds.org/messier/spir.html ] tilted about 45 degrees with a bright compact nucleus and prominent lanes of dark dust [ http://antwrp.gsfc.nasa.gov/apod/ap980318.html ]. |
|
M83: The Southern Pinwheel G
…
| Title |
M83: The Southern Pinwheel Galaxy from VLT |
| Explanation |
M83 [ http://www.seds.org/messier/m/m083.html ] is one of the closest and brightest spiral galaxies [ http://www.seds.org/messier/spir.html ] on the sky. Visible with binoculars in the constellation of Hydra [ http://www.astro.wisc.edu/~dolan/constellations/ constellations/Hydra.html ], majestic spiral arms have prompted its nickname as the Southern Pinwheel. Although discovered 250 years ago, only much later [ http://antwrp.gsfc.nasa.gov/debate/debate20.html ] was it appreciated that M83 [ http://antwrp.gsfc.nasa.gov/cgi-bin/apod/apod_search?m83 ] was not a nearby gas cloud, but a barred spiral galaxy [ http://en.wikipedia.org/wiki/Barred_spiral_galaxies ] much like our own Milky Way Galaxy [ http://antwrp.gsfc.nasa.gov/apod/ap050825.html ]. M83, pictured above [ http://www.eso.org/outreach/press-rel/pr-1999/ pr-18-99.html ] in a photograph from a Very Large Telescope [ http://www.eso.org/projects/vlt/ ], is a prominent member of a group of galaxies that includes Centaurus A [ http://antwrp.gsfc.nasa.gov/apod/ap050717.html ] and NGC 5253, all of which lie about 15 million light years [ http://chandra.harvard.edu/photo/cosmic_distance.html ] distant. Several bright supernova explosions [ http://antwrp.gsfc.nasa.gov/apod/ap981230.html ] have been recorded in M83. An intriguing double circumnuclear ring [ http://antwrp.gsfc.nasa.gov/apod/ap011106.html ] has been discovered at the center of M83 [ http://antwrp.gsfc.nasa.gov/apod/ap030206.html ]. |
|
M83: The Southern Pinwheel G
…
| Title |
M83: The Southern Pinwheel Galaxy from VLT |
| Explanation |
M83 [ http://www.seds.org/messier/m/m083.html ] is one of the closest and brightest spiral galaxies [ http://www.seds.org/messier/spir.html ] on the sky. Visible with binoculars in the constellation of Hydra [ http://www.astro.wisc.edu/~dolan/constellations/constellations/Hydra.html ], majestic spiral arms have prompted its nickname as the Southern Pinwheel. Although discovered 250 years ago, only in this century was it appreciated that M83 [ http://antwrp.gsfc.nasa.gov/apod/ap990926.html ] was not a gas cloud [ http://antwrp.gsfc.nasa.gov/debate/debate20.html ] but a barred spiral galaxy [ http://www.smv.org/hastings/bsmain.htm ] much like our own Milky Way Galaxy [ http://antwrp.gsfc.nasa.gov/apod/ap971229.html ]. M83, pictured above [ http://www.eso.org/outreach/press-rel/pr-1999/pr-18-99.html ] in a recently released photograph from a Very Large Telescope [ http://www.eso.org/projects/vlt/ ], is a prominent member of a group of galaxies that includes Centaurus A [ http://antwrp.gsfc.nasa.gov/apod/ap990822.html ] and NGC 5253, all of which lie about 15 million light years distant. To date, six supernova explosions [ http://antwrp.gsfc.nasa.gov/apod/ap981230.html ] have been recorded in M83. An unusual double circumnuclear ring [ http://adsabs.harvard.edu/cgi-bin/nph-bib_query?bibcode=1998AJ....116.2834E ] has recently been discovered at the center of M83 [ http://antwrp.gsfc.nasa.gov/apod/ap970419.html ] and is still being investigated. |
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Neptune's "Hot" South Pole
PIA09927
Sol (our sun)
Mid-infrared Camera/Spectrom
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| Title |
Neptune's "Hot" South Pole |
| Original Caption Released with Image |
These thermal images show a "hot" south pole on the planet Neptune. These warmer temperatures provide an avenue for methane to escape out of the deep atmosphere. The images were obtained with the Very Large Telescope in Chile, using an imager/spectrometer for mid-infrared wavelengths on Sept. 1 and 2, 2006. The telescope is operated by the European Organization for Astronomical Research in the Southern Hemisphere (known as ESO). Scientists say Neptune's south pole is "hotter" than anywhere else on the planet by about 10 degrees Celsius (50 degrees Fahrenheit). The average temperature on Neptune is about minus 200 degrees Celsius (minus 392 degrees Fahrenheit). The upper left image samples temperatures near the top of Neptune's troposphere (near 100 millibar pressure, which is one-tenth the Earth atmospheric pressure at sea level). The hottest temperatures are indicated at the lower part of the image, at Neptune's south pole (see the graphic at the upper right). The lower two images, taken 6.3 hours apart, sample temperatures at higher altitudes in Neptune's stratosphere. They do show generally warmer temperatures near, but not at, the south pole. They also show a distinct warm area which can be seen in the lower left image and rotated completely around the back of the planet and returned to the earth-facing hemisphere in the lower right image. |
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