... Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. August 21, 1998 . A Massive Cluster In A Young Universe . ... Explanation: Conventional theories suggest that this cluster of galaxies should not exist . ... One explanation for this cluster's presence is that the Universe we live in is not massive enough to eventually halt its expansion - contradicting some current standard views of cosmology . ...

... 2000 January 4 . Galaxies Cluster Toward the Great Attractor . ... The galaxies pictured above are part of a cluster of galaxies called ACO 3627 near the center of the Great Attractor . ... The Great Attractor is a diffuse mass concentration fully 250 million light-years away, but so large it pulls our own Milky Way Galaxy and millions of others galaxies towards it. Many of the galaxies in ACO 3627 are slowly heading towards collisions with each other. ... About APOD > . ...

... A Massive Cluster In A Young Universe . ... 21.08.1998 . ... NASA Explanation: Conventional theories suggest that this cluster of galaxies should not exist . ... One explanation for this cluster's presence is that the Universe we live in is not massive enough to eventually halt its expansion - contradicting some current standard views of cosmology . ... Publications with keywords: cosmology - universe - galaxy cluster . Publications with words: cosmology - universe - galaxy cluster . ...

... HUBBLE DISCOVERS BLACK HOLES IN UNEXPECTED PLACES . ... Even more odd, these new black holes were found in the cores of glittering, "beehive" swarms of stars -- called globular star clusters -- that orbit our Milky Way and other galaxies. ... Supermassive black holes found by Hubble in the centers of galaxies represent about 0.5 percent of the galaxies' mass. Amazingly, the black holes now found in star clusters, which are 10,000 times less massive than a galaxy, also obey this trend. ...

A Canadian and American team of Astronomers have used the 305-m wide Arecibo radio dish, the world's largest and most sensitive radio telescope, to uncover a dozen new super-fast-spinning pulsars. The team directed their search for these rare and exotic stars by pointing the Arecibo radio telescope towards massive star clusters, called Globular Clusters, orbiting our Milky Way galaxy. ... One of the most exotic residents in the Globular cluster system are the millisecond pulsars. ...

Stellar Clusters are very useful laboratories for empirically studying stellar evolution. ... All cluster stars are at the same distance . All cluster stars have the same physical age . ... CM diagram Young Cluster In this case we see the Main Sequence fully represented. The blue dots represent massive stars with short main sequence lifetimes. ... Thus, identifying the most massive star which is still on the main sequence is an effective means of determining the age of a stellar cluster. ...

... Over the first 4 years, its X-ray telescopes eROSITA and ART-XC will survey the whole sky with a record sensitivity in the 0.5-10 keV energy band. ... The goal of the second international Spectrum-RG conference is to discuss the different scientific topics addressed by the mission, synergies with surveys at other wavelengths, and requirements to follow-up observations.Contributed talks and poster presentations are invited on the topics related to the SRG science goals. ... Active galactic nuclei . ...