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... Tonight's Sky . ... The Magazine . ... Star Atlas . ... An artificial comet holds secrets to Earths life . ... Astronomy for Kids . ... Observing springtime deep-sky objects with a large telescope . ... The planet has extreme temperature swings and perhaps active lava flows. ... A digital supplement to Astronomy magazine. ... Join TravelQuest International with Astronomy and Discover magazines on one of three great tour options surrounding this celestial spectacle . ... Astronomy Magazine . ...

... Our Sun is part of a huge wheel-shaped collection of stars. ... Astronomers have long suspected it was a very massive black hole, and that every galaxy had such a central mass, created early in the history of the universe. ... However, unless that object happens to be headed directly at the black hole (a relatively small target) it will just swing around and fly away again, like a comet making a pass at the Sun. The velocity acquired in falling towards the black hole also helps it escape. ...

Astronotes Armagh Planetarium's Stellar Blog! ... Solar System . ... Planets . ... This bizarrely shrunken planetary system was found by NASAтАЩs Kepler mission, hence the parent star has been named Kepler-11. ... Planetary scientist and Kepler science team member Jack Lissauer said ?These six planets are mixtures of rock and gases, possibly including water.тАЭ €аNone of these strange new worlds are likely to be home to any form of life; their surface conditions are simply too extreme. ...

The radius of the event horizon of a black hole with the mass of the Sun would be about 3 kilometers, about the same size as your city, town or village. If the Earth could be compressed into a black hole, the radius of its event horizon would be 1/330,000 of this, because the mass of the Earth is 1/330,000 times the mass of the Sun. ... 30,000,000 . ... 20,000 . ... Black hole event horizon . ... MYTH: All stars collapse to become black holes upon their death. ... MYTH: Black holes are very dense. ...

... Staff . ... Cosmic dust has been observed both in emission and extinction everywhere in our Galaxy as well as in many other galaxies. ... Dust grains are classically thought to form in the winds of Asymptotic Giant Branch (AGB) stars. However, nowadays there is increasing observational evidence for notable dust formation in Supernovae (SNe). ... Hence the observed dust mass of 0.7вИТ0.9M вКЩ in this source can be safely considered as indicative of the mass of freshly formed dust in SN ejecta. ...

... SS433 is a close binary system, one star is a supergiant, a second one is a black hole. ... Even a black hole cannot accept such an enormous mass flux, a supercritical accretion disk appears, all the excess gas glows up to several tens of thousands degrees and is ejected off the disk with enormous velocities. ... SAO researchers have found an evidence of the supercritical accretion onto a black hole in SS433, which follows from a brightness variability of the SS433 disk. ...

... At full throttle the Deep Space 1 spacecraft's innovative ion drive produces about 1/50th of a pound of thrust ... a force so great that it would just about hold up a piece of paper on planet Earth! ... This exotic system - thought to be a stellar mass black hole consuming matter from a companion star - was discovered only last year as a flaring celestial x-ray source. ... Stars are born in M16's Eagle Nebula, a stellar nursery 7,000 light-years from Earth toward the constellation Serpens. ...

... HUBBLE UNCOVERS DUST DISK AROUND A MASSIVE BLACK HOLE . Resembling a gigantic hubcap in space, a 3,700 light-year-diameter dust disk encircles a 300 million solar-mass black hole in the center of the elliptical galaxy NGC 7052. ... Because the jets in NGC 7052 are not perpendicular to the disk, it may indicate that the black hole and the dust disk in NGC 7052 do not have a common origin. ... NGC 7052 is located in the constellation of Vulpecula, 191 million light-years from Earth. ...