... Credit Copyright: Data - Hubble Legacy Archive , ESA , NASA ; Processing - Roberto Colombari Explanation: How far away is spiral galaxy NGC 4921? ... Since NGC 4921 is a member of the Coma Cluster of Galaxies , refining its distance would also allow a better distance determination to one of the largest nearby clusters in the local universe. The magnificent spiral NGC 4921 has been informally dubbed anemic because of its low rate of star formation and low surface brightness . ...

... 2007 May 29 . Bright Spiral Galaxy M81 from Hubble . Credit: NASA , ESA , and the Hubble Heritage Team ( STScI / AURA ) . Explanation: The Hubble Space Telescope has resolved individual stars in a spectacular new image of nearby spiral galaxy M81. ... Edwin Hubble was able to use individual Cepheid variable stars to show that M31 was not nearby swirling gas but rather an entire galaxy like our Milky Way Galaxy . ... Light takes about 12 million years to reach us from M81. ... About APOD | ...

Hubble Observations Shed New Light on Jupiter Collision . Was it a comet or an asteroid? ... Their initial findings, combined with results from other space-borne and ground-based telescopes, shed new light on Jupiter's atmospheric winds, its immense magnetic field, the mysterious dark debris from the impacts, and the composition of the doomed comet itself. ... Hubble's ultraviolet observations show the motion of very fine impact debris particles now suspended high in Jupiter's atmosphere. ...

... 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....

Astronotes Armagh Planetarium's Stellar Blog! ... Comets and Asteroids . ... Space Flight . ... Science Fiction . UFOs and Fringe Science . ... This close-up look at Comet ISON (C/2012 S1) is from NASAтАЩs Hubble Space Telescope. This image was captured on 10 April 2013, when the comet was at a distance of 386 million miles (slightly further than Jupiter) from the Sun. ... Image credit: NASA, ESA, J.-Y. Li (Planetary Science Institute), and the Hubble Comet ISON Imaging Science Team) . ...

... Comet Tutorial . ... On July 1, 1993 an image was taken with the Hubble Space Telescope (HST) that clearly shows at least 15 individual fragments in one image frame of the train. ... This made an accurate orbit (or orbits) difficult to determine; however, after numerous observations of the comet, astronmers determined that the comet had passed within 96,000 kilometers (60,000 miles) of the center of Jupiter or 25,000 kilometers (16,000 miles) from the cloud tops during the July 8, 1992, approach. ...

The HDF observations were carefully scheduled to minimize the effect of scattered light. Nevertheless, Scattered light from the bright earth produces a visible X pattern in about 25% of the HDF data frames. ... The filled-in portion of the histograms indicates data where the scatttered light patern is visible to the eye. ... A major difference between version 1 and version 2 of the data reduction was the treatment of scattered light. ... version 1 . ...

... Spacecraft . 29b. Satellites looking down . ... 29e. Explorers of distant space . ... The Hubble orbiting telescope. ... The Hubble telescope , in low Earth orbit, overcomes such limitations, in the visible range and in part of the UV. ... So fruitful was this observation that a second "deep field" exposure of such length, near the southern pole of the heavens, was recently conducted. ... Some satellites specialize in observing the Sun, such as the Japanese Yohkoh and NASA's SOHO . ...

... Visible Distribution of Galaxies. ... Features of Elliptical, Lens-Shaped, Spiral and Irregular Galaxies. Galaxies with Bar. ... Distribution of Surface Brightness of Surface and Spiral Galaxies. ... Color Characteristics of Galaxies. ... Methods of Galaxies' Mass Determination. ... Hidden Mass of Spiral Galaxies. ... Features of Dark Matter Distribution in E and SO Galaxies. ... The Whole Number of Galaxies and Their Density by the Results of Observation on the 'Hubble' Space Telescope. ...

In this gallery are many images of Low Surface Brightness Galaxies which have recently been discovered and analyzed. ... The central surface brightness of this galaxy is 24.28 . Malin 2 This galaxy is another huge disk galaxy with a scale length of 15 kpc and a redshift of 15000 km/a. The high surface brightness knot in one of its spiral arms actually has the same color, luminosity and H-alpha equivalent width as the entire Large Magellanic Cloud . ... Truly it is a Low Surface Brightness Galaxy. ...

... Ciel Espace, le magazine qui vous guide toujours plus loin . ... des pages consacr†йes †а la publication de vos photos Mais c'est aussi une vraie communaut†й avec laquelle partager votre passion et nourrir votre curiosit†й. Accueil La premi†иre c†йph†йide de Hubble . ... C'est en observant les †йtoiles variables de type c†йph†йide que l'astronome Edwin Hubble a mesur†й pour la premi†иre fois la distance de la galaxie M31 †а l'aide du t†йlescope Hooker de 2,5 m du mont Wilson, en 1923. ...

... We can help students grasp the significance of Hubble's extremely keen eye, and learn a bit about angles and math in the process, with the following in-class activity. ... Looking through binoculars or telescopes allows us to magnify a small section of the sky. To measure sizes or distances in that small section, astronomers divide a degree into 60 smaller pieces called arcminutes, and further subdivide minutes into 60 smaller sections called arcseconds. ... 30 feet = . ... 36 seconds . ...

LBV M33 varC in M33 . This page is devoted to information on Supernova M33varC in M33 . Basic information on this LBV, including the last reported brightness, on this Supernova can be found on the main page . Information on the original web pages for many of these images can be found on the links web page. ... This object, almost invisible for many years suddenly flared back to life in 2013. An LBV in outburst like this have been known flare into supernovae. ... 15.1 . ... Pedro Re' . ...

... The European HST Archive has been moved to ESA's European Space Astronomy Centre ( ESAC ), Spain, where most of ESA's Space Science Archives are located and operated from. ... The Space Telescope European Coordinating Facility (ST-ECF), jointly operated by ESA and the European Southern Observatory ( ESO ) was, until the end of 2010, the European HST science facility, supporting the European astronomy community in exploiting the research opportunities provided by the Hubble Space Telescope. ...

... Armagh Observatory, College Hill, Armagh BT61 9DG, +44 (0)28 3752 2928 . Comet C/2011 L4 (PANSTARRS) on 2012 August 9th. ... A new comet, called C/2011 L4 (PANSTARRS), is expected to become visible for a few weeks from approximately 10th March in the western sky after sunset. The comet has come from the Oort cloud, which comprises a vast swarm of comets surrounding the solar system and extending more than halfway to the nearest star, that is more than two light years from the Sun. ...

... Bad Astronomy . ... Bitesize Astronomy . ... Bad Astro Store . ... Slacker Astronomy . ... Keep Bad Astronomy close to your heart, and help make me filthy rich. ... Life Under the Moon . ... Seeing Jupiter's Moons . ... Time Zones and the Spherical Earth . A Companion to the Earth? ... December 19, 1999) . ... Big Moon, Little Moon . ... How Big is the Moon? ... 14, 2000) . ... 2008 Phil Plait. ... Subscribe to the Bad Astronomy Newsletter! Talk about Bad Astronomy on the BA Bulletin Board! ...

... Local Group velocity in km/s: where l is the Galactic longitude and b the Galactic latitude, and v sys is the systemic velocity in km/s. Distance in Mpc : We adopt the following distances for galaxies with small Local Group velocities (v LG NGC6822 0.490 Mpc ( Mateo 1998 ) DDO210 0.880 Mpc ( Mateo 1998 ) NGC0055 1.480 Mpc ( Mateo 1998 ) NGC0300 2.04 Mpc (Willick Batra 2001) ESO594-G004 1.060 Mpc ( Mateo ... absolute blue magnitude: with D in Mpc. ...

... The Galactic low-mass X-ray binary GS 2023+338 was discovered during the burst on May 22, 1989 with the Japanise satellite Ginga (aka Galaxy). The flux reached 17 crabs (this unit of flux measurement is an bright X-ray source, Crab Nebula) at 10-35 keV. ... No other radio telescope worldwide carried out multi-frequency measurements. ... Upon 14 days the radio flux fell below the detection level at the RATAN-600 in relation to the decrease of the X-ray flux. ...

... The remote planet Pluto and its moon Charon orbit the Sun at a mean distance of almost 6,000 million kilometres, or nearly fourty times farther out than the Earth. During a recent investigation by an international group of astronomers [1], the best picture ever of Pluto and Charon [2] was secured with the European Space Agency's Faint Object Camera at the Hubble Space Telescope (HST). ... The new HST image was taken when Charon was near its maximum elongation from Pluto (0.9 arcseconds). ...

... One of this year's largest mass ejections from the Sun's atmosphere was recorded last Sunday by TESIS telescopes aboard the CORONAS-PHOTON satellite ( video - wmv 4.3 MB ). ... Over the course of a week, two gigantic solar prominences were simultaneously ejected from the surface of the Sun. ... Earth will not feel the Sun's influence either. ... The TESIS observatory ї TESIS: www.tesis.lebedev.ru . ... One of this year's largest mass ejections from the Sun's atmosphere (movie WMV, 4.3 MB) . ...