... Armagh Observatory, College Hill, Armagh BT61 9DG, +44 (0)28 3752 2928 . ... Risks Comparable to NEOs . ... The Increasing Rate of Discovery of Asteroids . ... Comet and Asteroid Collision Probabilities . ... Extreme albedo comets and the impact hazard (PDF Format) . ... Asteroid Impact Animations . ... Workshop on Scientific Requirements for Mitigation of Hazardous Comets and Asteroids - 2002 . ... The Spaceguard Survey Report, 1992 (PDF) . Tsunami from Asteroid/Comet Impacts . ...

... 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! ...

... 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. ...

... Special Reports Giant space cloud may be powered by black holes 17:57 23 April 2007 NewScientist.com news service David Shiga An enormous cloud of roiling plasma in space may be drawing its energy from black holes, new observations suggest. Such clouds might be sources for the mysterious particles that occasionally crash into Earth's atmosphere at ultra - high speed. ... But higher energy particles in the cloud may be able to escape, he says. ...

The Sun is our nearest star and the source of energy for life on Earth. ... For centuries astronomers wondered whether they were clouds floating in the Sun's atmosphere, but we now know that they really are huge regions of magnetic field, about as intense as the field at the poles of an iron magnet. ... Such abrupt events were named solar flares , and what made them especially interesting was that occasionally, after a prominent flare, a magnetic storm would erupt on Earth. ...

... 2000 January 17 . V4641 Sgr: The Closest Black Hole Candidate . ... Explanation: An object many astronomers believe is a black hole has been found only 1500 light-years from Earth, making it the closest black hole candidate . ... Astronomers are working to understand why V4641 acts strangely even for a black hole , as the explosions it creates fade within minutes, and appear at different times in different bands of light . ... About APOD | ...

... Feeding the Monster: Gas Caught in its Death Spiral into a Massive Black Hole . ... Stromlo Professor Mike Dopita have used the Hubble Space Telescope to discover how a massive Black Hole in a nearby galaxy feeds itself. ... Earlier Hubble Telescope data obtained by another team member, Professor Holland Ford of Johns Hopkins University in Baltimore, Maryland, had found a disk of gas rushing around the Black Hole at a speed of 500 kilometers a second. ...

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. ...

... X-rays are made up of photons that are emitted from stars, or quasars, or supernovae, the sun, or simply: anything that is undergoing a change either in size or temperature or giving out heat. ... in an X-ray binary star system, in which one normal star's orbit is crossed by a neutron star, when the neutron star by means of gravitational pull takes matter from the normal star X-rays form. ... Artists conception of a normal star (HDE 226868) and a black hole taking matter from the normal star. ...

... Science . ... Science Users Information > Science Activities > PhD Thesis Topics offered by ESO Faculty Members . ... Science Users Information . ... Data Handling and Products . ... Science Data Products Forum . ... ESO Data . ... ESO Data Access Policy . ... ESO Science Newsletter . ... ESO astronomers often are working on scientific programmes and data sets that are suited for PhD theses. This page gives an overview over what is currently offered by Faculty astronomers. ... Thesis topic . ...

... This year's eclipse is unique in duration. ... Although, at the present time, there are 6 solar observatories belonging to leading space agencies in orbit around the Earth, the eclipse of 22 July, 2009, will only be seen by two of them: the Russian CORONAS-PHOTON satellite equipped with TESIS telescopes and Japan's HINODE satellite fitted with an XRT space telescope. ... TESIS will be the first of the two devices (and the very first on Earth) to witness the solar eclipse. ...

... Events . ... The Event Horizon Telescope: Observing Black Holes with Schwarzschild-Radius Resolution . ... Galaxy lies a super massive black hole - 4 million times more massive . ... Universe to spatially resolve and image a black hole Event Horizon. ... For the much more massive (6 billion solar mass) black hole . ... for assembling a submm-VLBI Event Horizon Telescope. ... emission near the event horizon of super massive black holes. ... Copyright (c) Amateur Telescope Makers of Boston, Inc. ...

... JSC Oral History . NASA History . ... NASA Oral History Project: Earth System Science at 20 . This NASA Oral History Project features recollections from those who significantly contributed to the launch and evolution of Earth System Science. These interviews were gathered as part of the 20th anniversary of the Earth System Science Program. ... NASA Headquarters, Washington D.C. Program Manager , Stratospheric Theory and Data Analysis, Earth Science and Applications Division . ...