Images Credit & Copyright: IMAGE 1: European Southern Observatory (ESO) MPG/ESO 2.2 meter telescope at La Silla Observatory in Chile. IMAGE 2: NASA/ESA Hubble Space Telescope.
Located a fairly close 13,000 light years away in the southern constellation Pavo, (The Peacock) is this beautiful globular star cluster cataloged as NGC 6752. This cluster is not only beautiful; at an apparent magnitude of 5.5, it’s the third brightest globular cluster in the night sky. Can you guess the other two? I’ll tell you below but just as a hint I’ll say they are also southern hemisphere objects (I know right?!).
This cluster spans about 100 light years in diameter and contains within its cloud about 100,000 stars. At roughly 11 billion years old, it’s more than twice the age of our solar system and possibly as old as the Milky Way itself. There’s been quite a bit of research done on this object, mainly because of its proximity to us as one of the closer globulars to Earth. That doesn’t mean that it’s boring by any means. In fact it’s been found that a large number of the stars in the core of this object are binary (almost 40 percent). In addition to that, throughout the entire cluster are stars known as “blue stragglers.” These are stars that are much too young and massive to, well, be where they are. But, there they are! The leading hypothesis for this, states that they’re a result not of new star formation but instead, are a result of stellar collisions and mergers.
The headline image here was captured by the European Southern Observatory (ESO) MPG/ESO 2.2 meter telescope at La Silla Observatory in Chile. It gives us a beautiful view of the entire cluster. That “diamond” or bright blue star in the image is actually a nearby star that happened to find itself in the line of sight of NGC 6752 from our vantage point here on Spaceship Earth. The second image is a close up view of the core region and was captured by the NASA/ESA Hubble Space Telescope. I suppose that kind of makes this an impromptu “Zoom” post.
Oh, and before I forget; as I stated above, this is the third brightest globular star cluster in our night sky. The top two are; Omega Centauri (brightest) and 47 Tucanae or just 47 Tuc. Maybe we can hit those two next!
NAME: New General Catalog 6752, NGC 6752,
WHAT IS IT?: Globular star cluster.
HOW FAR AWAY IS IT?: 13,000 light years.
HOW BIG IS IT?: Roughly 100 light years with the core region 1.3 light years in diameter and the entire cluster measures almost as large as the Full Moon.
HOW OLD IS IT?: Roughly 11 billion years old.
DISCOVERY: Scottish astronomer, James Dunlop on June 30, 1826.
APPARENT MAGNITUDE? (Brightness from Earth): Naked eye visible 5.4.
WHERE IS IT? (General): Constellation Pavo, (The Peacock).
WHERE IS IT? (Exact RA/DEC J2000): RA 19h 10m 52.11s / DEC –59° 59′ 04.4″.
ESO page for the 1st image: http://www.eso.org/public/usa/images/eso1323a/
ESA Space Telescope page for the 2nd image: https://www.spacetelescope.org/images/potw1205a/