Showing posts with label open star cluster. Show all posts
Showing posts with label open star cluster. Show all posts

23 July 2014

Star Cluster NGC 3293 Nestled Against Clouds of Gas and Dust in the Carina Constellation



ESO’s La Silla Observatory in Chile released a striking image of star cluster NGC 3293 with clouds of glowing red gas and streaks of dust in the background. NGC is composed of young stars are believed to be less than ten million years old and is about 8000 light-years from Earth in the constellation of Carina (The Keel).

Using the Wide Field Imager (WFI) installed on the MPG/ESO 2.2-meter telescope at the observatory, astronomers study young star clusters such as NGC 3293 to learn more about the evolution of stars.

Star cluster are groups of stars that are held together by their own gravitational fields. Open star clusters and globular are the two types of clusters. NGC 3293 is an open star cluster; loosely clustered groups of young stars. The gravitational attraction between the stars in an open star cluster may be weak or non existent.

Globular star clusters are made up of hundreds of thousands of very old stars that are gravitationally bound. These stars are attracted to each other and form a very tight sphere. The stars within a globular star cluster orbit a galactic core and the amount of stars within get denser going toward the center.

These open clusters each formed from a giant cloud of molecular gas and their stars are held together by their mutual gravitational attraction. But these forces are not enough to hold a cluster together against close encounters with other clusters and clouds of gas as the cluster’s own gas and dust dissipates. So, open clusters will only last a few hundred million years, unlike their big cousins, the globular clusters, which can survive for billions of years, and hold on to far more stars.

19 February 2014

Star Cluster Messier 7 Shines Bright At The Tail End of The Scorpion



Star Cluster Messier 7 can be found shining brightly at the end of the tail end of the constellation Scorpius (The Scorpion). This group of stars is also known as Ptolemy's Cluster in honor of Claudius Ptolemy who discovered this star cluster around 130 AD. As the name implies, it is the 7th entry of Charles Messier's Catalog of Nebulae and Star Clusters done in 1764.

Messier 7 is about 800 light years from the Earth and is comprised of about 100 stars. It is a bright patch of stars that is visible to the naked eye found near the tail of the Scorpius constellation.

The latest images from the European Southern Observatory's Wide Field Imager on the MPG/ESO 2.2-metre telescope shows Messier 7 shining like diamonds against the backdrop of a multitude of stars.

These bright stars are believed to be close to exploding into a supernova as it is over 200 million years old.

Messier 7 is an open star cluster. Open star clusters are loose clustered groups of stars that are held together by a very weak gravitational attraction to each other.