Andrew Yee[_1_]
February 6th 08, 01:43 AM
ESO Education and Public Relations Dept.
----------------------------------------------------------------------------
Text with all links and the photos are available on the ESO Website at URL:
http://www.eso.org/public/outreach/press-rel/pr-2008/pr-02-08.html
----------------------------------------------------------------------------
For Immediate Release: 21 January 2008
ESO Press Photo 02/08
Cosmic Interactions
VLT images triplet of dancing galaxies
An image based on data taken with ESO's Very Large Telescope reveals a
triplet of galaxies intertwined in a cosmic dance.
The three galaxies, catalogued as NGC 7173 (top), 7174 (bottom right) and
7176 (bottom left), are located 106 million light-years away towards the
constellation of Piscis Austrinus (the 'Southern Fish').
NGC 7173 and 7176 are elliptical galaxies, while NGC 7174 is a spiral galaxy
with quite disturbed dust lanes and a long, twisted tail. This seems to
indicate that the two bottom galaxies -- whose combined shape bears some
resemblance to that of a sleeping baby -- are currently interacting, with
NGC 7176 providing fresh material to NGC 7174. Matter present in great
quantity around the triplet's members also points to the fact that NGC 7176
and NGC 7173 have interacted in the past.
Astronomers have suggested that the three galaxies will finally merge into a
giant 'island universe', tens to hundreds of times as massive as our own
Milky Way.
The triplet is part of a so-called 'Compact Group', as compiled by Canadian
astronomer Paul Hickson in the early 1980s. The group, which is the 90th
entry in the catalogue and is therefore known as HCG 90, actually contains
four major members. One of them -- NGC 7192 -- lies above the trio, outside
of this image, and is another peculiar spiral galaxy.
Compact groups are small, relatively isolated, systems of typically four to
ten galaxies in close proximity to one another. Another striking example is
Robert's Quartet. Compact groups are excellent laboratories for the study of
galaxy interactions and their effects, in particular the formation of stars.
As the striking image reveals, there are many other galaxies in the field.
Some are distant ones, while others seem to be part of the family. Studies
made with other telescopes have indeed revealed that the HCG 90 group
contains 16 members, most of them much smaller in size than the four members
with an entry in the NGC catalogue.
Notes
A list of all the work about this group of galaxies can be for example
obtained through the Simbad astronomical database.
Elliptical galaxies are smooth and featureless entities, often composed of
older, low mass stars, which produce very few new stars. Spiral galaxies
consist of a flat, rotating disc of stars, gas and dust, and a central
concentration of stars known as the bulge. The spiral arms are sites of
ongoing star formation. Our own Milky Way is a spiral galaxy.
National contacts for the media:
Belgium: Dr. Rodrigo Alvarez, +32-2-474 70 50
Czech Republic: Pavel Suchan, +420 267 103 040
Finland: Ms. Tiina Raivo, +358 9 7748 8369
Denmark: Dr. Michael Linden-Vnle, +45-33-18 19 97
France: Dr. Daniel Kunth, +33-1-44 32 80 85
Germany: Dr. Jakob Staude, +49-6221-528229
Italy: Dr. Leopoldo Benacchio, +39-347-230 26 51
The Netherlands: Ms. Marieke Baan, +31-20-525 74 80
Portugal: Prof. Teresa Lago, +351-22-089 833
Spain: Dr. Miguel Mas-Hesse, +34918131196
Sweden: Dr. Jesper Sollerman, +46-8-55 37 85 54
Switzerland: Dr. Martin Steinacher, +41-31-324 23 82
United Kingdom: Mr. Peter Barratt, +44-1793-44 20 25
USA: Dr. Paola Rebusco, +1-617-308-2397
----------------------------------------------------------------------------
ESO Press Information is available on Receive email notification
the WWW at about important news from
http://www.eso.org/outreach/press-rel/ ESO - subscribe to the
ESO-NEWS Mailing List.
----------------------------------------------------------------------------
Copyright ESO Education & Public Relations Department
Karl-Schwarzschild-Strasse 2, D-85748 Garching, Germany
----------------------------------------------------------------------------
----------------------------------------------------------------------------
Text with all links and the photos are available on the ESO Website at URL:
http://www.eso.org/public/outreach/press-rel/pr-2008/pr-02-08.html
----------------------------------------------------------------------------
For Immediate Release: 21 January 2008
ESO Press Photo 02/08
Cosmic Interactions
VLT images triplet of dancing galaxies
An image based on data taken with ESO's Very Large Telescope reveals a
triplet of galaxies intertwined in a cosmic dance.
The three galaxies, catalogued as NGC 7173 (top), 7174 (bottom right) and
7176 (bottom left), are located 106 million light-years away towards the
constellation of Piscis Austrinus (the 'Southern Fish').
NGC 7173 and 7176 are elliptical galaxies, while NGC 7174 is a spiral galaxy
with quite disturbed dust lanes and a long, twisted tail. This seems to
indicate that the two bottom galaxies -- whose combined shape bears some
resemblance to that of a sleeping baby -- are currently interacting, with
NGC 7176 providing fresh material to NGC 7174. Matter present in great
quantity around the triplet's members also points to the fact that NGC 7176
and NGC 7173 have interacted in the past.
Astronomers have suggested that the three galaxies will finally merge into a
giant 'island universe', tens to hundreds of times as massive as our own
Milky Way.
The triplet is part of a so-called 'Compact Group', as compiled by Canadian
astronomer Paul Hickson in the early 1980s. The group, which is the 90th
entry in the catalogue and is therefore known as HCG 90, actually contains
four major members. One of them -- NGC 7192 -- lies above the trio, outside
of this image, and is another peculiar spiral galaxy.
Compact groups are small, relatively isolated, systems of typically four to
ten galaxies in close proximity to one another. Another striking example is
Robert's Quartet. Compact groups are excellent laboratories for the study of
galaxy interactions and their effects, in particular the formation of stars.
As the striking image reveals, there are many other galaxies in the field.
Some are distant ones, while others seem to be part of the family. Studies
made with other telescopes have indeed revealed that the HCG 90 group
contains 16 members, most of them much smaller in size than the four members
with an entry in the NGC catalogue.
Notes
A list of all the work about this group of galaxies can be for example
obtained through the Simbad astronomical database.
Elliptical galaxies are smooth and featureless entities, often composed of
older, low mass stars, which produce very few new stars. Spiral galaxies
consist of a flat, rotating disc of stars, gas and dust, and a central
concentration of stars known as the bulge. The spiral arms are sites of
ongoing star formation. Our own Milky Way is a spiral galaxy.
National contacts for the media:
Belgium: Dr. Rodrigo Alvarez, +32-2-474 70 50
Czech Republic: Pavel Suchan, +420 267 103 040
Finland: Ms. Tiina Raivo, +358 9 7748 8369
Denmark: Dr. Michael Linden-Vnle, +45-33-18 19 97
France: Dr. Daniel Kunth, +33-1-44 32 80 85
Germany: Dr. Jakob Staude, +49-6221-528229
Italy: Dr. Leopoldo Benacchio, +39-347-230 26 51
The Netherlands: Ms. Marieke Baan, +31-20-525 74 80
Portugal: Prof. Teresa Lago, +351-22-089 833
Spain: Dr. Miguel Mas-Hesse, +34918131196
Sweden: Dr. Jesper Sollerman, +46-8-55 37 85 54
Switzerland: Dr. Martin Steinacher, +41-31-324 23 82
United Kingdom: Mr. Peter Barratt, +44-1793-44 20 25
USA: Dr. Paola Rebusco, +1-617-308-2397
----------------------------------------------------------------------------
ESO Press Information is available on Receive email notification
the WWW at about important news from
http://www.eso.org/outreach/press-rel/ ESO - subscribe to the
ESO-NEWS Mailing List.
----------------------------------------------------------------------------
Copyright ESO Education & Public Relations Department
Karl-Schwarzschild-Strasse 2, D-85748 Garching, Germany
----------------------------------------------------------------------------