Featured Research

from universities, journals, and other organizations

Diamonds in the tail of the scorpion: Star cluster Messier 7

Date:
February 19, 2014
Source:
European Southern Observatory - ESO
Summary:
A new image shows the bright star cluster Messier 7. Easily spotted with the naked eye close to the tail of the constellation of Scorpius, it is one of the most prominent open clusters of stars in the sky, making it an important astronomical research target.

This new image from the Wide Field Imager on the MPG/ESO 2.2-metre telescope at ESO's La Silla Observatory in Chile, shows the bright star cluster Messier 7, also known as NGC 6475. Easily spotted by the naked eye in the direction of the tail of the constellation of Scorpius (The Scorpion), this cluster is one of the most prominent open clusters of stars in the sky and an important research target.
Credit: ESO

A new image from ESO's La Silla Observatory in Chile shows the bright star cluster Messier 7. Easily spotted with the naked eye close to the tail of the constellation of Scorpius, it is one of the most prominent open clusters of stars in the sky -- making it an important astronomical research target.

Messier 7, also known as NGC 6475, is a brilliant cluster of about 100 stars located some 800 light-years from Earth. In this new picture from the Wide Field Imager on the MPG/ESO 2.2-metre telescope it stands out against a very rich background of hundreds of thousands of fainter stars, in the direction of the centre of the Milky Way.

At about 200 million years old, Messier 7 is a typical middle-aged open cluster, spanning a region of space about 25 light-years across. As they age, the brightest stars in the picture -- a population of up to a tenth of the total stars in the cluster -- will violently explode as supernovae. Looking further into the future, the remaining faint stars, which are much more numerous, will slowly drift apart until they become no longer recognisable as a cluster.

Open star clusters like Messier 7 are groups of stars born at almost the same time and place, from large cosmic clouds of gas and dust in their host galaxy. These groups of stars are of great interest to scientists, because the stars in them have about the same age and chemical composition. This makes them invaluable for studying stellar structure and evolution.

An interesting feature in this image is that, although densely populated with stars, the background is not uniform and is noticeably streaked with dust. This is most likely to be just a chance alignment of the cluster and the dust clouds. Although it is tempting to speculate that these dark shreds are the remnants of the cloud from which the cluster formed, the Milky Way will have made nearly one full rotation during the life of this star cluster, with a lot of reorganisation of the stars and dust as a result. So the dust and gas from which Messier 7 formed, and the star cluster itself, will have gone their separate ways long ago.

The first to mention this star cluster was the mathematician and astronomer Claudius Ptolemy, as early as 130 AD, who described it as a "nebula following the sting of Scorpius," an accurate description given that, to the naked eye, it appears as a diffuse luminous patch against the bright background of the Milky Way. In his honour, Messier 7 is sometimes called Ptolemy's Cluster. In 1764 Charles Messier included it as the seventh entry in his Messier catalogue. Later, in the 19th century, John Herschel described the appearance of this object as seen through a telescope as a "coarsely scattered cluster of stars" -- which sums it up perfectly.


Story Source:

The above story is based on materials provided by European Southern Observatory - ESO. Note: Materials may be edited for content and length.


Cite This Page:

European Southern Observatory - ESO. "Diamonds in the tail of the scorpion: Star cluster Messier 7." ScienceDaily. ScienceDaily, 19 February 2014. <www.sciencedaily.com/releases/2014/02/140219075205.htm>.
European Southern Observatory - ESO. (2014, February 19). Diamonds in the tail of the scorpion: Star cluster Messier 7. ScienceDaily. Retrieved July 22, 2014 from www.sciencedaily.com/releases/2014/02/140219075205.htm
European Southern Observatory - ESO. "Diamonds in the tail of the scorpion: Star cluster Messier 7." ScienceDaily. www.sciencedaily.com/releases/2014/02/140219075205.htm (accessed July 22, 2014).

Share This




More Space & Time News

Tuesday, July 22, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

Raw: Cargo Craft Undocks from Space Station

Raw: Cargo Craft Undocks from Space Station

AP (July 22, 2014) A Russian Soyuz cargo-carrying spacecraft undocked from the International Space Station on Monday. The craft is due to undergo about ten days of engineering tests before it burns up in the Earth's atmosphere. (July 22) Video provided by AP
Powered by NewsLook.com
NASA Ceremony Honors Moon Walker Neil Armstrong

NASA Ceremony Honors Moon Walker Neil Armstrong

AP (July 21, 2014) NASA honored one of its most famous astronauts Monday by renaming a historic building at the Kennedy Space Center in Florida. It now bears the name of Neil Armstrong, the first man to walk on the moon. (July 21) Video provided by AP
Powered by NewsLook.com
Neil Armstrong's Post-Apollo 11 Life

Neil Armstrong's Post-Apollo 11 Life

Newsy (July 19, 2014) Neil Armstrong gained international fame after becoming the first man to walk on the moon in 1969. But what was his life like after the historic trip? Video provided by Newsy
Powered by NewsLook.com
This Week @ NASA, July 18, 2014

This Week @ NASA, July 18, 2014

NASA (July 18, 2014) Apollo 11 yesterday, Next Giant Leap tomorrow, Science instruments for Europa mission, and more... Video provided by NASA
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins