ESO Messier 7: Diamonds in the tail of the scorpion - Video

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.

ESA ESO Image: Scorpius, the Cosmic Lobster

A star-forming region of the Milky Way looks oddly like a "cosmic lobster" in this photo. 

CREDIT: ESO/VVV Survey/D. Minniti. Acknowledgement: Ignacio Toledo

A new photo by a telescope in Chile has captured an amazing view of wispy interstellar clouds creating what appears to be a "cosmic lobster" in a distant star nursery, scientists say.

The new image, released today (Feb. 20) by the European Southern Observatory, reveals the nebula NGC 6357 about 8,000 light years from Earth in the constellation Scorpius (the Scorpion). Massive, hot, blue stars dot the wisps of gas and dust in the stellar nursery.

The space cloud formation is also known as the "Lobster nebula" because of its appearance in visible-light images, ESO officials explained in a statement. ESO astronauts also unveiled a new video of the Lobster nebula to accompany the new image.



"One of the bright young stars in NGC 6357, known as Pismis 24-1, was thought to be the most massive star known — until it was found to actually be made up of at least three huge bright stars, each with a mass of under 100 times that of our sun," ESO officials said in the image description. "Even so, these stars are still heavyweights — some of the most massive in our Milky Way. Pismis 24-1 is the brightest object in the Pismis 24 star cluster, a bunch of stars that are all thought to have formed at the same time within NGC 6357."

The picture was taken using the infrared spectrum of light. While other photos of NGC 6357 have been taken in the visible spectrum, this time scientists used infrared imaging to cut through dust and debris in the foreground and get a more clear understanding of the shrouded nebula.

ESO's Visible and Infrared Survey Telescope for Astronomy at the Paranal Observatory in Chile took the photo as part of a huge sky survey named the VISTA Variables in the Vía Láctea that will image the "central parts of the galaxy."

"VISTA is the largest and most powerful survey telescope ever built, and is dedicated to surveying the sky in infrared light," ESO officials said in a statement. "The VVV survey is scanning the central bulge and some of the plane of our galaxy to create a huge dataset that will help astronomers to discover more about the origin, early life, and structure of the Milky Way."