... No one was quite sure, but the answer is giving clues to the nature of mysterious dark matter . In the case of MACSJ0025.4-1222 , two huge clusters of galaxies have been found slowly colliding over hundreds of millions of years, and the result has been imaged by both the Hubble Space Telescope in visible light and the Chandra Space Telescope in X-ray light . ... Publications with keywords: cluster of galaxies - dark matter . Publications with words: cluster of galaxies - dark matter . ...

... 2005 September 26 . Streams of Stars in the Virgo Cluster of Galaxies . ... After hundreds of 15-minute exposures taken over two months in early 2004, the result is a dramatically deep and wide angle image of Virgo , the closest cluster of galaxies to our Milky Way Galaxy . ... Inspection of the above image shows unusually large halos for the brightest galaxies as well as unusual faint streams of stars connecting Virgo galaxies that previously appeared unrelated. ... 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. September 22, 1998 . M61: Virgo Spiral Galaxy . ... Explanation: M61 is a barred spiral galaxy located in the nearby Virgo Cluster of Galaxies . Visible in M61 are a host of features common to spiral galaxies : bright spiral arms , a central bar , dust lanes , and bright knots of stars. ... About APOD > . ...

... These Frontier Fields will combine the power of HST with the natural gravitational telescopes of high-magnification clusters of galaxies. ... We are soliciting gravitational lensing maps for the last four Hubble Frontier Fields clusters (MACSJ0717.5+3745, MACSJ1149.5+2223, AbellS1063, and Abell 370) based upon the exceptionally deep HST FF imaging and other new ancillary data. ... For the full set of proposal instructions and requirements, see the FY16 Frontier Fields Lensing Map Call for Proposals....

Astronotes Armagh Planetarium's Stellar Blog! ... Stars . ... Starbursts are short-lived events, stars are forming so quickly that the reservoirs of interstellar gas from which stars are coalescing would be used up on a timescale much shorter than the age of the galaxy . ... Strong stellar winds from giant new stars in the starburst region combine with the blasts of supernovae to push a mighty flood of extremely hot gas, a ?superwind? from the galaxy thousands of light years into intergalactic space. ...

M1 image More About M1 Nice Color Picture . ... M16 image More About M16 HST image . ... M31 image More About M31 Nice Color Picture . ... M42 image ; M43 image More About M42/43 Nice Color CCD Picture . M51 image More About M51 Color Image of M51 M51 Supernova . M57 image More About M57 Nice Color CCD Picture Very Deep M57 Image . ... M81 image More About M81 M81 Supernova Ultraviolet Image of M81 More about Ultraviolet Imaging . M82 image More About M82 M82 False Color M82 True Color . ...

... Tonight's Sky . ... The Magazine . ... Observing . ... The double star 54 Leonis, spiral galaxy NGC 3198, and emission nebula NGC 3199 . ... Astronomy for Kids . ... Observing springtime deep-sky objects with a large telescope . ... Bright planets meet at dusk . ... Astronomy magazine subscribers can read the full article for free. ... Get instant access to subscriber content on Astronomy.com! ... Receive news, sky-event information, observing tips, and more from Astronomy's weekly email newsletter....

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. ...

... Our Milky Way galaxy is host to a number of companions. These companions are gravitationally bound to the Milky Way and are stellar systems in their own right. They include a population of about 150 globular clusters (GCs) and some 30 dwarf satellite galaxies (DSGs). ... These DSGs are more extended and diffuse compared to GCs. In fact the larger satellites of the Milky Way (and other galaxies, for that matter) host their own small systems of GCs. ...

... 145Slee,Roy Savage We present detailed radio and optical parameters for the stronger radio sources in 58 Abell cluster fields observed with the Very Large Array (VLA) using scaled arrays at 1.5 and 4.9 GHz. ... The cluster fields were distributed over 24 h of RA and between declinations +35 deg and -30 deg. ... Optical identifications Cluster Source Radio Centroid Optical Position EF Ang. ...

... Science . ... Science Users Information > Science and Technical Meetings > Conferences 2011 > Dynamics of Low-Mass Stellar Systems: From Star Clusters to Dwarf Galaxies . ... Science Users Information . ... Observing with ESO Telescopes . ... Science Software . ... ESO-MIDAS . ... Science Data Products Forum . ... ESO Data . ... ESO Science Newsletter . ... We aim at bringing together a mix of astronomers from both observations and theory that work on the dynamics of dwarf galaxies and star clusters...