|
|
Thread Tools | Display Modes |
#1
|
|||
|
|||
Three Dusty Beauties: New Portraits of Spiral Galaxies NGC 613, NGC1792 and NGC 3627 (Forwarded)
ESO Education and Public Relations Dept.
Contacts: Richard West European Southern Observatory Garching bei München, Germany Phone: +49 89 3200 6276 ---------------------------------------------------------------------------- Text with all links and the photos are available on the ESO Website at URL: http://www.eso.org/outreach/press-re...hot-33-03.html ---------------------------------------------------------------------------- For immediate release: 19 December 2003 ESO Press Photos 33a-c/03 Three Dusty Beauties New Portraits of Spiral Galaxies NGC 613, NGC 1792 and NGC 3627 Not so long ago, the real nature of the "spiral nebulae", spiral-shaped objects observed in the sky through telescopes, was still unknown. This long-standing issue was finally settled in 1924 when the famous American astronomer Edwin Hubble provided conclusive evidence that they are located outside our own galaxy and are in fact "island universes" of their own. Nowadays, we know that the Milky Way is just one of billions of galaxies in the Universe. They come in vastly different shapes -- spiral, elliptical, irregular -- and many of them are simply beautiful, especially the spiral ones. Astronomers Mark Neeser from the Universitäts-Sternwarte München (Germany) and Peter Barthel from the Kapteyn Institute in Groningen (The Netherlands) were clearly not insensitive to this when they obtained images of three beautiful spiral galaxies with ESO's Very Large Telescope (VLT). They did this in twilight during the early morning when they had to stop their normal observing programme, searching for very distant and faint quasars. The resulting colour images (ESO PR Photos 33a-c/03) were produced by combining several CCD images in three different wavebands from the FORS multi-mode instruments. The three galaxies are known as NGC 613, NGC 1792 and NGC 3627. They are characterized by strong far-infrared, as well as radio emission, indicative of substantial ongoing star-formation activity. Indeed, these images all display prominent dust as well as features related to young stars, clear signs of intensive star-formation. NGC 613 PR Photo 33a/03 of the barred spiral galaxy NGC 613 was obtained with the FORS1 and FORS2 multi-mode instruments (at VLT MELIPAL and YEPUN, respectively) on December 16-18, 2001. It is a composite of three exposures in different wavebands, cf. the technical note below. The full-resolution version of this photo retains the original pixels. Note the many arms and the pronounced dust bands. North is up and East is left. NGC 613 is a beautiful barred spiral galaxy in the southern constellation Sculptor. This galaxy is inclined by 32 degrees and, contrary to most barred spirals, has many arms that give it a tentacular appearance. Prominent dust lanes are visible along the large-scale bar. Extensive star-formation occurs in this area, at the ends of the bar, and also in the nuclear regions of the galaxy. The gas at the centre, as well as the radio properties are indicative of the presence of a massive black hole in the centre of NGC 613. NGC 1792 PR Photo 33b/03 shows the starburst spiral galaxy NGC 1792. Note the numerous background galaxies in this sky field. North is up and East is to the left. NGC 1792 is located in the southern constellation Columba (The Dove) -- almost on the border with the constellation Caelum (The Graving Tool) -- and is a so-called starburst spiral galaxy. Its optical appearance is quite chaotic, due to the patchy distribution of dust throughout the disc of this galaxy. It is very rich in neutral hydrogen gas -- fuel for the formation of new stars -- and is indeed rapidly forming such stars. The galaxy is characterized by unusually luminous far-infrared radiation; this is due to dust heated by young stars. M 66 (NGC 3627) PR Photo 33c/03 of the spiral galaxy M 66 (or NGC 3627). North towards upper left, West towards upper right. The third galaxy is NGC 3627, also known as Messier 66, i.e. it is the 66th object in the famous catalogue of nebulae by French astronomer Charles Messier (1730 - 1817). It is located in the constellation Leo (The Lion). NGC 3627 is a beautiful spiral with a well-developed central bulge. It also displays large-scale dust lanes. Many regions of warm hydrogen gas are seen throughout the disc of this galaxy. The latter regions are being ionised by radiation from clusters of newborn stars. Very active star-formation is most likely also occurring in the nuclear regions of NGC 3627. The galaxy forms, together with its neighbours M 65 and NGC 3628, the so-called "Leo Triplet"; they are located at a distance of about 35 million light-years. M 66 is the largest of the three. Its spiral arms appear distorted and displaced above the main plane of the galaxy. The asymmetric appearance is most likely due to gravitational interaction with its neighbours. Technical Information: The images were taken by Mark Neeser (Universitäts-Sternwarte München, Germany) and Peter Barthel (Kapteyn Astronomical Institute, Netherlands) during twilight on the nights of 16-18 December 2001 with the FORS multi-mode instruments attached to the VLT-MELIPAL (FORS1) or VLT-YEPUN (FORS2). Each galaxy was observed in three different wavebands for up to 300 seconds per waveband, and the image obtained in each waveband was associated to a colour: B (blue), V (green) and R (red). Neeser and Barthel also performed the first stage of the image processing; further processing and colour-encoding was made by Hans-Herman Heyer and Henri Boffin (ESO). ---------------------------------------------------------------------------- ESO Press Information is available on Receive email notification the WWW at about important news from ESO - http://www.eso.org/outreach/press-rel/. subscribe to the ---------------------------------------------------------------------------- (c) ESO Education & Public Relations Department Karl-Schwarzschild-Strasse 2, D-85748 Garching, Germany ---------------------------------------------------------------------------- |
#2
|
|||
|
|||
Three Dusty Beauties: New Portraits of Spiral Galaxies NGC 613, NGC 1792 and NGC 3627 (Forwarded)
Andrew Yee wrote in message m...
ESO Education and Public Relations Dept. Contacts: Richard West European Southern Observatory Garching bei München, Germany Phone: +49 89 3200 6276 ---------------------------------------------------------------------------- Text with all links and the photos are available on the ESO Website at URL: http://www.eso.org/outreach/press-re...hot-33-03.html ---------------------------------------------------------------------------- For immediate release: 19 December 2003 ESO Press Photos 33a-c/03 Andrew- very much appreciate your contributions! To my untrained eye, NGC 613 appears to be rotating on two axis! Comment? Jim G Three Dusty Beauties New Portraits of Spiral Galaxies NGC 613, NGC 1792 and NGC 3627 Not so long ago, the real nature of the "spiral nebulae", spiral-shaped objects observed in the sky through telescopes, was still unknown. This long-standing issue was finally settled in 1924 when the famous American astronomer Edwin Hubble provided conclusive evidence that they are located outside our own galaxy and are in fact "island universes" of their own. Nowadays, we know that the Milky Way is just one of billions of galaxies in the Universe. They come in vastly different shapes -- spiral, elliptical, irregular -- and many of them are simply beautiful, especially the spiral ones. Astronomers Mark Neeser from the Universitäts-Sternwarte München (Germany) and Peter Barthel from the Kapteyn Institute in Groningen (The Netherlands) were clearly not insensitive to this when they obtained images of three beautiful spiral galaxies with ESO's Very Large Telescope (VLT). They did this in twilight during the early morning when they had to stop their normal observing programme, searching for very distant and faint quasars. The resulting colour images (ESO PR Photos 33a-c/03) were produced by combining several CCD images in three different wavebands from the FORS multi-mode instruments. The three galaxies are known as NGC 613, NGC 1792 and NGC 3627. They are characterized by strong far-infrared, as well as radio emission, indicative of substantial ongoing star-formation activity. Indeed, these images all display prominent dust as well as features related to young stars, clear signs of intensive star-formation. NGC 613 PR Photo 33a/03 of the barred spiral galaxy NGC 613 was obtained with the FORS1 and FORS2 multi-mode instruments (at VLT MELIPAL and YEPUN, respectively) on December 16-18, 2001. It is a composite of three exposures in different wavebands, cf. the technical note below. The full-resolution version of this photo retains the original pixels. Note the many arms and the pronounced dust bands. North is up and East is left. NGC 613 is a beautiful barred spiral galaxy in the southern constellation Sculptor. This galaxy is inclined by 32 degrees and, contrary to most barred spirals, has many arms that give it a tentacular appearance. Prominent dust lanes are visible along the large-scale bar. Extensive star-formation occurs in this area, at the ends of the bar, and also in the nuclear regions of the galaxy. The gas at the centre, as well as the radio properties are indicative of the presence of a massive black hole in the centre of NGC 613. NGC 1792 PR Photo 33b/03 shows the starburst spiral galaxy NGC 1792. Note the numerous background galaxies in this sky field. North is up and East is to the left. NGC 1792 is located in the southern constellation Columba (The Dove) -- almost on the border with the constellation Caelum (The Graving Tool) -- and is a so-called starburst spiral galaxy. Its optical appearance is quite chaotic, due to the patchy distribution of dust throughout the disc of this galaxy. It is very rich in neutral hydrogen gas -- fuel for the formation of new stars -- and is indeed rapidly forming such stars. The galaxy is characterized by unusually luminous far-infrared radiation; this is due to dust heated by young stars. M 66 (NGC 3627) PR Photo 33c/03 of the spiral galaxy M 66 (or NGC 3627). North towards upper left, West towards upper right. The third galaxy is NGC 3627, also known as Messier 66, i.e. it is the 66th object in the famous catalogue of nebulae by French astronomer Charles Messier (1730 - 1817). It is located in the constellation Leo (The Lion). NGC 3627 is a beautiful spiral with a well-developed central bulge. It also displays large-scale dust lanes. Many regions of warm hydrogen gas are seen throughout the disc of this galaxy. The latter regions are being ionised by radiation from clusters of newborn stars. Very active star-formation is most likely also occurring in the nuclear regions of NGC 3627. The galaxy forms, together with its neighbours M 65 and NGC 3628, the so-called "Leo Triplet"; they are located at a distance of about 35 million light-years. M 66 is the largest of the three. Its spiral arms appear distorted and displaced above the main plane of the galaxy. The asymmetric appearance is most likely due to gravitational interaction with its neighbours. Technical Information: The images were taken by Mark Neeser (Universitäts-Sternwarte München, Germany) and Peter Barthel (Kapteyn Astronomical Institute, Netherlands) during twilight on the nights of 16-18 December 2001 with the FORS multi-mode instruments attached to the VLT-MELIPAL (FORS1) or VLT-YEPUN (FORS2). Each galaxy was observed in three different wavebands for up to 300 seconds per waveband, and the image obtained in each waveband was associated to a colour: B (blue), V (green) and R (red). Neeser and Barthel also performed the first stage of the image processing; further processing and colour-encoding was made by Hans-Herman Heyer and Henri Boffin (ESO). ---------------------------------------------------------------------------- ESO Press Information is available on Receive email notification the WWW at about important news from ESO - http://www.eso.org/outreach/press-rel/. subscribe to the ---------------------------------------------------------------------------- (c) ESO Education & Public Relations Department Karl-Schwarzschild-Strasse 2, D-85748 Garching, Germany ---------------------------------------------------------------------------- |
#3
|
|||
|
|||
Three Dusty Beauties: New Portraits of Spiral Galaxies NGC 613, NGC 1792 and NGC 3627 (Forwarded)
"JG" == Jim Greenfield writes:
Text with all links and the photos are available on the ESO Website at URL: http://www.eso.org/outreach/press-re...hot-33-03.html [...] NGC 613 PR Photo 33a/03 of the barred spiral galaxy NGC 613 was obtained with the FORS1 and FORS2 multi-mode instruments (at VLT MELIPAL and YEPUN, respectively) on December 16-18, 2001. It is a composite of three exposures in different wavebands, cf. the technical note below. The full-resolution version of this photo retains the original pixels. Note the many arms and the pronounced dust bands. North is up and East is left. NGC 613 is a beautiful barred spiral galaxy in the southern constellation Sculptor. This galaxy is inclined by 32 degrees and, contrary to most barred spirals, has many arms that give it a tentacular appearance. Prominent dust lanes are visible along the large-scale bar. Extensive star-formation occurs in this area, at the ends of the bar, and also in the nuclear regions of the galaxy. The gas at the centre, as well as the radio properties are indicative of the presence of a massive black hole in the centre of NGC 613. JG [...] To my untrained eye, NGC 613 appears to be rotating on two JG axis! Comment? Perhaps you are seeing the bar? -- Lt. Lazio, HTML police | e-mail: No means no, stop rape. | http://patriot.net/%7Ejlazio/ sci.astro FAQ at http://sciastro.astronomy.net/sci.astro.html |
#4
|
|||
|
|||
Three Dusty Beauties: New Portraits of Spiral Galaxies NGC 613, NGC 1792 and NGC 3627 (Forwarded)
Joseph writes:
"JG" == Jim Greenfield writes: Text with all links and the photos are available on the ESO Website at URL: http://www.eso.org/outreach/press-re...hot-33-03.html NGC 613 is a beautiful barred spiral galaxy in the southern constellation Sculptor. This galaxy is inclined by 32 degrees and, contrary to most barred spirals, has many arms that give it a tentacular appearance. Prominent dust lanes are visible along the large-scale bar. Extensive star-formation occurs in this area, at the ends of the bar, and also in the nuclear regions of the galaxy. The gas at the centre, as well as the radio properties are indicative of the presence of a massive black hole in the centre of NGC 613. JG [...] To my untrained eye, NGC 613 appears to be rotating on two JG axis! Comment? Perhaps you are seeing the bar? I've believed the same thing of NGC 613 -- as well as for a few other galaxies -- for quite some time now. The galaxy appears as if it is composed of two planes tilted in respect to one another, one older and the other newer. The prominent bar that stretches furthest out to the left in the image is the newer. In NGC 613's instance, the lefthand portion of the bar appears to be above the plane of the earlier ring, and the righthand portion of the bar seems to be below it. Wirt Atmar |
#5
|
|||
|
|||
Three Dusty Beauties: New Portraits of Spiral Galaxies NGC 613, NGC 1792 and NGC 3627 (Forwarded)
"WA" == Wirt Atmar writes:
WA Joseph writes: "JG" == Jim Greenfield writes: Text with all links and the photos are available on the ESO Website at URL: http://www.eso.org/outreach/press-re...hot-33-03.html JG [...] To my untrained eye, NGC 613 appears to be rotating on two JG axis! Comment? Perhaps you are seeing the bar? WA I've believed the same thing of NGC 613 -- [...] -- for quite some WA time now. The galaxy appears as if it is composed of two planes WA tilted in respect to one another, one older and the other WA newer. The prominent bar that stretches furthest out to the left WA in the image is the newer. WA In NGC 613's instance, the lefthand portion of the bar appears to WA be above the plane of the earlier ring, and the righthand portion WA of the bar seems to be below it. I'll have to confess that I'm not sure I see this. I can sort of see how one might think that one of the arms is stretching out "above" the rest of the disk. However, one always has to remember that we are viewing things in projection and obtaining distances can be tricky. It might be possible to check this with spectral-line observations of H I or CO or something like that, but I am wary of reaching that conclusion based on the image alone. Also I don't think that the dust lanes are leading the bar. Thus, dust lane of the leading arm of the bar could more distinct (and "above"?) as compared to the dust lane of the trailing arm. It is also not required that the be exactly symmetric; one might be somewhat more dusty than the other. I can't rule out what you're saying, but as I indicate above, I'm wary of reaching the conclusion based solely on an image. -- Lt. Lazio, HTML police | e-mail: No means no, stop rape. | http://patriot.net/%7Ejlazio/ sci.astro FAQ at http://sciastro.astronomy.net/sci.astro.html |
Thread Tools | |
Display Modes | |
|
|