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Latest Globular cluster Stories

7e102fc9ac484ff28afa02408e68399d1
2009-10-29 09:20:00

Star clusters are among the most visually alluring and astrophysically fascinating objects in the sky. One of the most spectacular nestles deep in the southern skies near the Southern Cross in the constellation of Crux. The Kappa Crucis Cluster, also known as NGC 4755 or simply the "Jewel Box" is just bright enough to be seen with the unaided eye. It was given its nickname by the English astronomer John Herschel in the 1830s because the striking color contrasts of its pale blue and orange...

03ce92324db663537810a077060a51261
2009-07-09 15:40:00

The tight cluster of stars surrounding a supermassive black hole after it has been violently kicked out of a galaxy represents a new kind of astronomical object and a fossil record of the kick. A paper published in the July 10 issue of The Astrophysical Journal discusses the theoretical properties of "hypercompact stellar systems" and suggests that hundreds of these faint star clusters might be detected at optical wavelengths in our immediate cosmic environment. Some of these objects may...

1636f4d2fe58158cd76751e07a2e9ff21
2009-04-29 10:20:00

It sounds like the plot of a sci-fi movie: rogue black holes roaming our galaxy, threatening to swallow anything that gets too close. In fact, new calculations by Ryan O'Leary and Avi Loeb (Harvard-Smithsonian Center for Astrophysics) suggest that hundreds of massive black holes, left over from the galaxy-building days of the early universe, may wander the Milky Way. Good news, however: Earth is safe. The closest rogue black hole should reside thousands of light-years away. Astronomers are...

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2009-04-24 08:15:00

Twenty-four unusual stars, 18 of them newly discovered, have been observed in new Hubble telescope images. The stars are white dwarfs, a common type of dead star, but they are odd because they are made of helium rather than the usual carbon and oxygen. This is the first extensive sequence of helium-core white dwarfs to be observed in a globular cluster, a dense swarm of some of the oldest stars in our galaxy. A study, accepted for publication in the Astrophysical Journal, suggests that these...

4d45289e9ee9e3629a495ca533222cff1
2009-04-16 11:38:41

This composite image shows the massive galaxy cluster MACSJ0717.5+3745 (MACSJ0717, for short) where four separate galaxy clusters have been involved in a collision, the first time such a phenomenon has been documented. Hot gas is shown in an image from NASA's Chandra X-ray Observatory and galaxies are shown in an optical image from NASA's Hubble Space Telescope. The hot gas is color-coded to show temperature, where the coolest gas is reddish purple, the hottest gas is blue, and the...

f3ac9d3af99fd18dfbe37a435c20a213
2009-04-07 15:25:00

A new Hubble image highlights striking swirling dust lanes and glittering globular clusters in oddball galaxy NGC 7049. The NASA/ESA's Hubble Space Telescope has captured this image of NGC 7049, a mysterious looking galaxy on the border between spiral and elliptical galaxies. NGC 7049 is found in the constellation of Indus, and is the brightest of a cluster of galaxies, a so-called Brightest Cluster Galaxy (BCG). Typical BCGs are some of the oldest and most massive galaxies. They provide...

2009-03-11 09:55:00

GREENBELT, Md., March 11 /PRNewswire-USNewswire/ -- A new map combining nearly three months of data from NASA's Fermi Gamma-ray Space Telescope is giving astronomers an unprecedented look at the high-energy cosmos. To Fermi's eyes, the universe is ablaze with gamma rays from sources ranging from within the solar system to galaxies billions of light-years away. (Logo: http://www.newscom.com/cgi-bin/prnh/20081007/38461LOGO) "Fermi has given us a deeper and better-resolved view of the...

326847e802c0b0af5991c9192dab92641
2009-01-14 16:01:46

Researchers have discovered that the mysterious overweight stars known as blue stragglers are the result of "Ëœstellar cannibalism' where plasma is gradually pulled from one star to another to form a massive, unusually hot star that appears younger than it is. The process takes place in binary stars "“ star systems consisting of two stars orbiting around their common centre of mass. This helps to resolve a long standing mystery in stellar evolution. The research, which is part...

5dc54d542934983894e6fb6a0abde2a71
2008-09-20 08:30:35

A team led by a Yale University astronomer has discovered the least luminous, most dark matter-filled galaxy known to exist. The galaxy, called Segue 1, is one of about two dozen small satellite galaxies orbiting our own Milky Way galaxy. The ultra-faint galaxy is a billion times less bright than the Milky Way, according to the team's results, to be published in an upcoming issue of The Astrophysical Journal (ApJ). But despite its small number of visible stars, Segue 1 is nearly a thousand...

a05c699ddc1b2e013653e6f7fcf44ddd1
2008-08-20 18:35:00

Black holes are sometimes huge cosmic beasts, billions of times the mass of our sun, and sometimes petite with just a few times the sun's mass. But do black holes also come in size medium? A new study suggests that, for the most part, the answer is no. Astronomers have long suspected that the most likely place to find a medium-mass black hole would be at the core of a miniature galaxy-like object called a globular cluster. Yet nobody has been able to find one conclusively. Now, a team of...


Latest Globular cluster Reference Libraries

6_ee73912f0568b7aab1fb32a3d250b7b82
2004-10-19 04:45:42

Star Cluster -- Star clusters are physically bound systems of stars. In order of low compactness to high compactness (and in some sense also age) they range from stellar associations to open clusters to globular clusters. Star clusters are held together by the gravitation of their members. Due to both external (encounters with massive objects, influence of the host galaxy) and internal (encounters with other cluster members, stellar evolution) influences, clusters slowly evaporate. Their...

6_46f1290db7aabf07d0480393fea260ed2
2004-10-19 04:45:41

Globular Cluster -- A globular cluster is a cluster of stars that is spherical in shape and extremely dense towards its core. Globular clusters are usually composed of hundreds of thousands of old stars, similar to the bulge of a spiral galaxy but confined to a volume of only a few cubic parsecs. Some globular clusters (like Omega Centauri in our Milky Way, and G1 in M31) are truly massive clusters, with several million times the mass of our Sun. Such globular clusters may be the...

6_e40db84a4338b0529465bda1f7ad78d62
2004-10-19 04:45:41

Galaxy -- Stars are almost always found in collections called galaxies, together with gas, dust, and large amounts of dark matter detected by its gravitational effects. These are all held together by gravitational attraction and orbit a common centre. There is some evidence that black holes may exist at the centre of some or most galaxies. Galaxies come in three main types: ellipticals, spirals, and irregulars. A slightly more extensive description of galaxy types is given by the Hubble...

3_8c23adba28ac23ddb6954b79674339f42
2004-10-19 04:45:40

Virgo A Galaxy -- Discovered 1781 by Charles Messier. The giant elliptical galaxy M87, also called Virgo A, is one of the most remarkable objects in the sky. It is perhaps the dominant galaxy in the closest big cluster to us, the famous Virgo Cluster of galaxies (sometimes also called "Coma-Virgo cluster" which is more acurate, as it extends into constellation Coma), and lies at the distance of this cluster (about 60 million light-years). M87 lies well in the heart of the Virgo cluster...

3_b44b7fd989f2076cfeda5fc743f39ab02
2004-10-19 04:45:40

Milky Way Galaxy -- The Milky Way (a translation of the Latin Via Lactea, in turn derived from the Greek Galaxia (gala, galactos means "milk")) is a hazy band of white light across the night sky formed by billions of stars in the disc of our galaxy. The Milky Way appears brightest in the direction of Sagittarius, where the galactic centre lies. Relative to the celestial equator, the Milky Way passes as far north as the constellation of Cassiopeia and as far south as the constellation of...

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