Astronotes Armagh Planetarium's Stellar Blog! ... Comets and Asteroids . ... Image credit:ESO/J.Emerson/VISTA. ... However others are less pessimistic and it has even been claimed that the mysterious ?Wow! signal? received in 1977 originated from the direction M55.б  Sadly, this still unexplained pulse of radio energy originated from a location rather to the northwest of M55 so I doubt if the source was this cluster (if indeed the signal was genuinely of extraterrestrial origin). ... Mysterious Wow! ...

... Jupiter's moon is the home to many powerful volcanoes so active they are effectively turning the moon inside out. The above time-lapse sequence is a composite of images taken during two space missions that approached the violent moon: Voyager and Galileo. ... On the 7th of October, 1959 (7/X/1959), the Soviet interplanetary station which has come to be called "Luna 3" successfully photographed the far side of the moon giving denizens of planet Earth their first ever view of this hidden hemisphere. ...

... 2002 December 29 . NGC 1818: A Young Globular Cluster . ... Explanation: Globular clusters once ruled the Milky Way . Back in the old days , back when our Galaxy first formed, perhaps thousands of globular clusters roamed our Galaxy . ... There are few, if any, young globular clusters in our Milky Way Galaxy because conditions are not ripe for more to form. ... Pictured above is a "young" globular cluster residing there: NGC 1818 . ... About APOD | ...

... Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. December 18, 1999 . Irregular Galaxy Sextans A . ... Their newly formed, bright, blue star clusters found along beautiful, symmetric spiral arms are guaranteed to attract attention. But small irregular galaxies form stars too , like this lovely, gumdrop-shaped galaxy, Sextans A . ... About APOD > . ...

home publications > mercury . ... Big Clusters, Tiny Galaxies . ... Astronomers struggle to understand why giant star clusters form in the tiniest of galaxies . ... These clusters are probably young versions of globular clusters, but they are commonly called super star clusters. Seven dwarf galaxies within 16 million light-years have formed super star clusters, with one of these galaxies, NGC 1569, possessing two young clusters. ... Super star clusters have a lot to tell us about star formation. ...

... Globular cluster NGC 2808, elliptical galaxy NGC 2986, and the Sextans Dwarf . ... Astronomy for Kids . ... Astronomy 101 . ... Astronomy Foundation . ... Do globular clusters form in a galaxy's halo or migrate in from outside? If the latter, how? ... The Milky Way Galaxy has a system of roughly 150 globular clusters, which are all older than 9 billion years. ... Get instant access to subscriber content on Astronomy.com! ... If you are already registered on Astronomy.com, please log in below. ...

... Two collections of galaxies, which are called galaxy clusters , collided. The resulting galaxy cluster that formed from the collision is called El Gordo, which means fat one in Spanish! ... A galaxy cluster like this, with El Gordo's huge size and found so far away in the Universe, is a very rare space object. ... To measure El Gordo s distance from Earth, astronomers used a telescope called the Very Large Telescope, which is based in the country Chile in South America. ...

The radial distribution of metallicity of star-forming galaxies in a galaxy cluster can inform us about the mass assembly and enrichment history of the galaxy cluster. ... Both galaxy clusters are cool-core clusters at redshift z т?? ... The gas-phase metallicity of star- forming galaxies in MACS1115+01 exhibit anti-correlation with projected distance т??0.15 ТБ 0.08 dex/Mpc, whereas the radial metallicity distribution of RXJ1532+30 is statistically flat (т??0.09 ТБ 0.12 dex/Mpc). ...

... Conventionally, globular clusters are thought to be massive conglomerations of metal poor stars formed during the early epochs of galaxy formation. However, recent studies show that some galaxies contain metal rich clusters which may have formed during a merger. We use broadband WFPC2 images to study the cluster systems of galaxies and attempt to trace the chemical, kinematic and merger history of the host galaxies. ...