... 2004 June 17 . Comet NEAT and the Beehive Cluster . ... But when a bright comet passed in front of a bright star cluster last month, binoculars and cameras were able to show off their marked differences in dramatic fashion. Pictured above, the bright comet, C/2001 Q4 (NEAT) shows many details of its coma and tail, while far in the distance the Beehive open cluster, M44 , shows many of its stars. ... About APOD | ... NASA Web Site Statements, Warnings, and Disclaimers . ...

... But when a bright comet passed in front of a bright star cluster last month, binoculars and cameras were able to show off their marked differences in dramatic fashion. Pictured above, the bright comet, C/2001 Q4 (NEAT) shows many details of its coma and tail, while far in the distance the Beehive open cluster, M44 , shows many of its stars. Comet Q4 has now faded to the edge of unaided visibility and can best be found with a sky map and binoculars from the Northern Hemisphere well into June. ...

Astronotes Armagh Planetarium's Stellar Blog! ... Space Flight . ... Earth Satellites . ... Leonid meteors seen from 13 km altitude aboard an aircraft during the 1999 Leonids Multi-Instrument Aircraft Campaign (Leonid-MAC). Comet Tempel-Tuttle provides the cometary debris for the Leonid meteor shower. ... Every 17-19 November Earth crosses Tempel-TuttleтАЩs orbit and the Leonids become visible. With clear, dark skies observers may see 10 to 15 Leonid meteors every hour on those mornings. ...

... Bad Astronomy . ... Bitesize Astronomy . ... Last week's Snack talked about how black holes can affect the environment around them in such a way as to be very bright . ... It's a common misconception that black holes always have matter swirling into them. ... As this matter gets closer and closer to the black hole it piles up and a large, fairly flat disk forms. This is called the accretion disk , because matter from this disk accretes (that is, falls in) on the black hole. ... 2008 Phil Plait. ...

... Armagh Observatory, College Hill, Armagh BT61 9DG, +44 (0)28 3752 2928 . See also images taken on November 22nd . Image taken by Andy McCrea who says, . To me the comet appears yellowish and it has gone from star-like to a . ... More images from Andy McCrea here . ... The true explanation is that a very faint comet, known as periodic comet Holmes, produced a massive outburst of material and became a million times brighter than it was just a day earlier. ... More images from Andy McCrea . ...

... 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) ...

... November 12, 1996 . Comet Hale-Bopp Passes M14 . ... Explanation : Comet Hale-Bopp continues its slow trek across the night sky, and can now be seen superposed near the bright globular cluster M14 . Will Comet Hale-Bopp become as bright in early 1997 as Comet Hyakutake did in early 1996? It is still too early to tell. ... Because of the size of coma , some speculate that the nucleus of Hale-Bopp is unusually large. ... Tomorrow's picture: Seven Jets from Comet Hale-Bopp . ... About APOD . ...

... Science User Portal . ... ESO, the European Southern Observatory . ... Travel and Contacts . Travel to ESO Headquarters . ... Survey Telescopes . ... Galaxy Clusters . ... Star Clusters . ... Stars@ESO . ... ESO Science Newsletter . ... ESO 3.6-metre telescope . ... MPG/ESO 2.2-metre telescope . ... ESO 1-metre Schmidt telescope . ... This chart shows the bright constellation of Scorpius (The Scorpion). ... The location of the bright star cluster Messier 7 €аis indicated with a red circle. ...

... Tonight's Sky . ... SUN MOON MERCURY VENUS MARS, JUPITER SATURN . ... Observing . ... Why do the constellations and the Moon appear upside down from the Southern Hemisphere? ... From the Southern Hemisphere, any object or constellation that lies near the celestial equator (the imaginary line that divides the northern and southern halves of the sky) would appear both upside down and reversed left to right compared to a northern perspective. ... Get instant access to subscriber content on Astronomy...

... To be read in conjunction with Section 4.11 of the WFPC2 Instrument Handbook , -Version 4.0. ... 1 The second study found evidence that CTE loss for faint stars has increased with time (Whitmore, 1998). The primary observational consequence of CTE loss is that a point source at the top of the chip appears to be fainter than if observed at the bottom of the chip, due to the loss of electrons as the star is read out down the chip (see Figure 1 ). ... Last updated: 06/16/98 10:38:00 . ...

... The awsome spectacle of a brilliant comet, with its long ghostly tail streaming behind it, is a rare event. ... Only one other comet, Comet Halley, was seen so far from the Sun, giving scientists an opportunity to watch it as it slowly warmed up and sprouted a tail. ... Comets are the Rip Van Winkles of the solar system -- mini-worlds that have changed little during their 4.5-billion-year nap far from the Sun. ... Observing Comets . ... Once, comets inhabited the entire solar system. ...

A team of U.S. and German astrophysicists have made the first ever detection of X-rays coming from a comet. ... Following the initial detection, the team reported repeated X-ray emissions from the comet over the next 24 hours. ... One preliminary theory is that X-ray emission from the Sun was absorbed by a cloud of gaseous water molecules surrounding the nucleus of the comet, and then were re-emitted by the molecules in a process physicists call "fluorescence." ... Comets . ...

... BLUE STRAGGLER STARS are unusually hot and bright stars found in the cores of ancient star clusters known as globulars. ... BACKGROUND (from wikipedia): Blue straggler stars are stars in open or globular clusters that are hotter and bluer than other cluster stars having the same luminosity. ... There is evidence in favor of this view, notably that blue straggler stars appear to be much more common in dense regions of clusters, especially in the cores of globular clusters. ...

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. ...

You Can Make Stellar Images Brighter . Articles | ... A few months ago I wrote an article titled "You Can’t Make Them Brighter". So why am I now writing that you can make them brighter. ... The image of a focused star is actually a small disk called the Airy disk, named after the 19 th century scientist Sir George Airy. ... For a given aperture, a smaller Airy disk means that the light is focused to a smaller disk and is therefore brighter. ... www.astronomy.net . About Astronomy Net | ...

... 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. ...

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ATMoB "Open Cluster Observing Award " Guidelines Purpose: To promote observing among the membership of the Amateur Telescope Makers of Boston through participation in the Open Clusters Observing Awards program. Introduction: This awards program is oriented towards visually observing open clusters above magnitude 9.9. ... It turns out that a very unprejudiced and convenient method to dermine the limiting magnitude is to count the number of visible stars in certain areas on the sky. ...

Results from 6m telescope observations of globular clusters in dwarf galaxies Sharina M. We consider properties of globular clusters in dwarf galaxies observed with the multi-slit unit of the SCORPIO spectrograph at the SAO 6m telescope. ... Studying GCs in dwarf galaxies at the faintest end of the galaxy luminosity function provides valuable information for a better understanding of galaxy evolution and evolutionary connection between globular clusters and nuclei of galaxies. ...

Supernovae 2010jl in UGC 5189A . This page is devoted to information on Supernova 2010jl in UGC 5189A . ... Astronomy Magazine's Supernova SN 2010jl . ... Bad Astronomy's SN 2010 JL in weird UGC 5189 . SpaceBanter.com 2010jl post . Blogbaker's 2010jl post . Joseph Brimacombe widefield color image . ... 2010/11/04.50 . ... 2010/11/05.203 . ... Joseph Brimacombe . 2010/11/05.467 . ... mirror . ... JM Llapasset . ... 2011/01/15.160 . ... Back to Bright Supernovae - 2010 . ...