... Through the Shadow of the Moon . ... What would it look like to fly through a total eclipse of the Sun? On a typical place on Earth in the path of the dark shadow of the Moon during a total eclipse, an observer would see the Moon cross the face of the Sun, completely blocking it for a few minutes. ... Just within planet Earth's shadow the Full Moon's disk is still easy to spot at its brief total phase. Full Moon in Earth's Shadow . ... In the Heart of the Virgo Cluster . ...

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! ...

... 2001 February 7 . Distant Open Cluster M103 . ... Explanation: Bright blue stars highlight the open cluster known as M103 . The gas clouds from which these stars condensed has long dispersed. ... In fact, a formerly blue star has recently evolved off the main sequence and is visible above as the red giant star near the cluster center. In general, yellow stars like our Sun are usually less bright and hence less prominent in open clusters than their massive blue cousins. ... About APOD | ...

... Bad Astronomy . ... Bitesize Astronomy . ... The next step up are true clusters, called open clusters . Open clusters (sometimes misleadingly called "galactic clusters") are groups of stars ranging in size from a few dozen stars up to tens of thousands. ... The youngest is about 1 or 2 million years old, while the oldest is about 6 or 7 billion years, making it just older than our own solar system. ... So by looking at the stars in the cluster we can tell pretty well how old they are. ...

Many intermediate-age star clusters in the Magellanic Clouds exhibit very unusual features in their colour-magnitude diagrams that suggest they may have formed their stars over periods spanning hundreds of millions of years per cluster. ... Nonetheless, this interpretation is enticing in the context of the formation of ancient globular clusters, which almost always exhibit puzzling abundance patterns that apparently require multiple episodes of star formation to explain. ...

... 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. ...

... Indeed, one alteration of orbits can be the outright ejection of a planet. When several big planets are orbiting a star under each other's influence, the system is inherently unstable. ... We know of no good reason why the smallest objects with fusion should have the same mass as the smallest objects that can form by themselves. ... 6) Mission Definition . ... I don't think this mission is impossible, and will suggest a definition in a future article in Mercury. ... Good luck! . ...

... STScI-PRC00-25 A DYING STAR IN GLOBULAR CLUSTER M15 The globular cluster Messier 15 is shown in this color image obtained with the NASA Hubble Space Telescope's Wide Field Planetary Camera 2 (WFPC2). ... Known as Kuestner 648, this was the first planetary nebula to be identified in a globular cluster. ... At the present time, the most massive stars remaining in M15 have about 80 percent of the mass of our Sun, a fact that makes the existence of a planetary nebula like K 648 something of a mystery. ...

... Science User Portal . ... Travel and Contacts . ... Galaxy Clusters . ... Star Clusters . ... This chart shows the constellation of Puppis (The Poop) and includes all the stars that can be seen with the unaided eye on a clear and dark night. This region of the sky includes some bright star clusters, chief amongst them Messier 47 (circled) and its contrasting sister cluster Messier 46. Both clusters are well seen in small telescopes, with Messier 47 having far fewer, but brighter, stars. ...

... The Pleiades star cluster, also known as the Seven Sisters and Messier 45, is a conspicuous object in the night sky with a prominent place in ancient mythology . ... The stars in the Pleiades are thought to have formed together around 100 million years ago, making them 1/50th the age of our sun, and they lie some 130 parsecs (425 light years ) away. ... Data for these stars are listed in a table below. ... Yes . ... WEBDA Pleiades cluster data . ... M45: The Pleiades Star Cluster (2007 November 18) ...

... Weidong Li, University of California - Berkeley . ... Abstract . ... A Snapshot Survey of The Most Massive Clusters of Galaxies . ... Keith S. Noll, Space Telescope Science Institute . ... Increasing the Accuracy of HST Astrometry with FGS1r . ... Satellite Search for Dawn Mission Targets, Vesta and Ceres . ... HST Observations of Titan's Escaping Atmosphere in Transit and in Emission . ... GO 11969: Satellite Search for Dawn Mission Targets, Vesta and Ceres . ... Past weeks: . ...

... Armagh Observatory, College Hill, Armagh BT61 9DG, +44 (0)28 3752 2928 . Portrait of Sir William Herschel (1738-1822) Royal Astronomical Society . Probably the most famous astronomer of the 18th century, Sir William Herschel discovered, in addition to the planet Uranus, many new nebulae, clusters of stars and binary stars. ... Other Herschel Family Portraits . Mirror by Herschel . Return to A Short History of Armagh Observatory . Last Revised: 2009 November 23rd . ...

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. ...

... Dept. for Astrometry & Space Geodynamics . ... Dept. for Physics of Stars&Galaxies . ... Dept. for Physics of Planetary Systems . ... Science . ... All Pages . ... Research of the stars with planets which pass apparent star disk (transiting exoplanets). The transit method based on a detection star brightness decrease during a passing of planet in front of its disk. Observed brightness system decries when planet pass star disk and its volume depend of the relative sizes star and planet. ...

... In typical nightly use, the wide field and planetary telescope and cameras record images of favorably placed objects in the sky, including constellations, bright variable stars, nebulae through narrow-band filters, comets, the Moon, and planets. ... Shared Skies telescopes are available for use by students at the University of Louisville and the University of Southern Queensland, and by teachers and students in middle and high schools mentored by faculty at the universities. ...

Class 1 Introduction, Background History of Modern Astronomy The Night Sky, Eclipses and the Seasons Kepler's Laws Newtonian Gravity General Relativity Matter and Light Telescopes Class 2 Solar System Characteristics Formation Exosolar Planets Class 3 Stars The Sun Stellar Evolution of Low and High Mass Stars Deaths of Stars Exotic Stars Class 4 Galaxies Galaxy Classification Formation of Galaxies Galactic Evolution ... So far, one planet has been studied by this method. ...

... With the stars gamma Can and delta Can , it forms another asterisms called " the Asses and the Manger ". ... Formed by the stars delta Ori, epsilon Ori and zeta Ori ; in Latin America it is called the " Three Marys ". ... Built by the four stars alpha UMa, beta UMa, gamma UMa and delta UMa . ... Formed by the four stars alpha Del , beta Del , gamma Del and delta Del . ... Also on Orion; the belt stars ( delta Ori , epsilon Ori and zeta Ori ), the sword and eta Ori build up this asterism. ...

The apparent path of the Sun across the sky. ... The path of the Sun across the celestial sphere is very close to that of the planets and the moon. ... In one year, as the Earth completes a full circuit around the Sun (drawing above), the Earth-Sun line and its continuation past Earth sweep the entire plane. ... Since the Sun and Earth are in the plane of the ecliptic, the line is automatically in that plane too; if the moon is also on the same line, it must be in the plane of the ecliptic as well. ...

... In the past used to check pn/ MOS cross calibration Example of old vs new pn/ mos Residuals in the form of ratio data / model for PN data on MOS best fitting model Example of old vs new pn/ mos Residuals in the form of ratio data / model for PN data on MOS best fitting model ACIS S3 vs EPIC pn · · Same thing, only now we compare Chandra ACIS S3 with ... Flux cross-cal · · The new HRMA calibration impacts on the ACIS/EPIC flux cross calibration. ...

... Future seminars . P a s t seminars . Seminar council . Stability of cold fronts in clusters of galaxies " . E. Churazov (IKI, MPA) . ... One of the insteresting results of Chandra and XMM-Newton observatories is the discovery of sharp structures in the X-ray surface brightness of galaxy clusters. These structures (a.k.a. cold fronts) are likely associated with the contacted discontinuities formed when a hot gas flows over a colder gravitationally bound gas cloud. ...