vendredi 20 mai 2016

Hubble Sees a Swarm of Ancient Star Clusters around a Galaxy











NASA - Hubble Space Telescope patch.

May 20, 2016


This NASA/ESA Hubble Space Telescope image shows star clusters encircling a galaxy, like bees buzzing around a hive. The hive in question is an edge-on lenticular galaxy NGC 5308, located just under 100 million light-years away in the constellation of Ursa Major (The Great Bear).

Members of a galaxy type that lies somewhere between an elliptical and a spiral galaxy, lenticular galaxies such as NGC 5308 are disk galaxies that have used up, or lost, the majority of their gas and dust. As a result, they experience very little ongoing star formation and consist mainly of old and aging stars. On Oct. 9, 1996, scientists saw one of NGC 5308’s aging stars meet dramatic demise, exploding as a spectacular Type la supernova.

Lenticular galaxies are often orbited by gravitationally bound collections of hundreds of thousands of older stars. Called globular clusters, these dense collections of stars form a delicate halo as they orbit around the main body of NGC 5308, appearing as bright dots on the dark sky.

The dim, irregular galaxy to the right of NGC 5308 is known as SDSS J134646.18+605911.9.

Hubble orbiting Earth

For images and more information about Hubble Space Telescope, visit:

    https://www.spacetelescope.org/
    http://hubblesite.org/
    http://www.nasa.gov/hubble

Image, Video,  Credits: ESA/Hubble & NASA; Acknowledgement: Judy Schmidt/Text Credits: European Space Agency (ESA)/NASA/Ashley Morrow.

Best regards, Orbiter.ch