January 10, 2013
European Southern Observatory Astronomers Capture New Image Of 47 Tucanae
[Watch the Video: A close look at the globular star cluster 47 Tucanae]
redOrbit Staff & Wire Reports - Your Universe OnlineUsing their Visible and Infrared Survey Telescope for Astronomy (VISTA), astronomers at the European Southern Observatory (ESO) have managed to capture a new infrared image of 47 Tucanae, the second most massive globular cluster in the galaxy.
The picture, which was released by the ESO on Thursday, depicts the cluster “in striking detail,” the observatory said in a statement. Also known as NGC 104, the globular cluster is located about 15,000 light-years from Earth, in the southern constellation of Tucana.
It is approximately 120 light-years across and is home to millions of stars, making it “one of the brightest and most massive globular clusters known and is visible to the naked eye,” they added.
Globular clusters such as 47 Tucanae are tremendously large, spherically-shaped clouds comprised of old stars that have been bound together by gravity. Much like natural satellites orbit their planets, these clusters circle around the cores of galaxies.
They contain little dust or gas, and it is believed that the majority of that material has either been blown from the cluster by explosions or winds from the stars within them, or peeled off as a result of interactions with interstellar gas, the ESO explained.
“These globular clusters spark a considerable amount of interest for astronomers,” they said. 47 Tucanae, in particular, has at its core many stars which the observatory describes as “exotic” with “unusual properties.” Studying objects within this cluster, and other like it, “may help us to understand how these oddballs form and interact.”
The image released on Thursday has a tremendous amount of depth and clarity because of the size, sensitivity, and location of the VISTA equipment, which is housed at the organization´s Paranal Observatory in Chile´s Atacama Desert. The photo was snapped as part of the VMC survey of the region of the Magellanic Clouds.
“47 Tucanae, although much closer than the Clouds, by chance lies in the foreground of the Small Magellanic Cloud (eso1008), and was snapped during the survey,” ESO officials said. “In amongst the swirling mass of stars at its heart lie many intriguing systems, including X-ray sources, variable stars, vampire stars, unexpectedly bright ℠normal´ stars known as blue stragglers (eso1243), and tiny objects known as millisecond pulsars, small dead stars that rotate astonishingly quickly.”
“Red giants, stars that have exhausted the fuel in their cores and swollen in size, are scattered across this VISTA image and are easy to pick out, glowing a deep amber against the bright white-yellow background stars,” they added. “The densely packed core is contrasted against the more sparse outer regions of the cluster, and in the background huge numbers of stars in the Small Magellanic Cloud are visible.”