... 2014 December 23 . The Cliffs of Comet Churyumov–Gerasimenko . ... They were discovered to be part of the dark nucleus of Comet Churyumov–Gerasimenko (CG) by Rosetta , a robotic spacecraft launched by ESA which began orbiting the comet in early August. ... Data from Rosetta indicates that the ice in Comet CG has a significantly different deuterium fraction -- and hence likely a different origin -- than the water in Earth's oceans. ... About APOD | ... A service of: ASD at NASA / GSFC . ...

... The Porpoise Galaxy from Hubble . ... Just a few hundred million years ago, NGC 2936, the upper of the two large galaxies shown, was likely a normal spiral galaxy -- spinning, creating stars -- and minding its own business. ... Its exact full phase (June 23, 11:32 UT) will occur shortly before it reaches perigee, the closest point to Earth in the Moon's orbit, and make it the largest Full Moon of 2013. ... APOD Turns Eighteen . ... The first APOD appeared eighteen years ago today, on 1995 June 16. ...

... Armagh Planetarium . ... Universe . ... January . ... Posted on January 21, 2011 | No Comments Don Pollacco, a research astronomer at Queens University Belfast, came to Armagh Planetarium to give a fascinating talk on exoplanets in January 2011. ... No Comments Armagh Planetarium kicked off 2011 in style with some amazing astronomy-based events in association with the€а BBC. Sinead McNicholl has a personal report of our part in the exciting Stargazing [ ] . ... Newer Entries . ...

... Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. December 22, 1996 . 18 Miles From Deimos . Credit: The Viking Project , NASA . ... Potato shaped and barely 6 miles wide this asteroid-like body was visited by the Viking 2 orbiter in 1977. This image was made when the spacecraft approached to within 18 miles of Deimos' surface. ... About APOD > . ... NASA Technical Rep.: ...

... It was designed to observe the solar wind approaching Earth, from a position near the Lagrangian point L1, and it is part of the International Solar-Terrestrial Physics (ISTP) Initiative . ... The original plan called for "Wind" to approach its final station over two years, undergoing two close encounters with the Moon to boost its speed. ... If however the object is moving , the encounter is not symmetric, and in the end the spacecraft may have gained or lost speed, depending on its trajectory. ...

... It was designed to observe the solar wind approaching Earth, from a position near the Lagrangian point L1, and it is part of the International Solar-Terrestrial Physics (ISTP) Initiative . ... The original plan called for "Wind" to approach its final station over two years, undergoing two close encounters with the Moon to boost its speed. ... If however the object is moving , the encounter is not symmetric, and in the end the spacecraft may have gained or lost speed, depending on its trajectory. ...

... The Cross-Quarter Days thus mark the middle of each season under our current system, or seasonal boundaries under the alternative system. ... Beltane / Bealtaine - Celtic bonfire festival May 4-7 2nd Cross-Quarter Day May 5 - Cinco de Mayo (Mexico) May 2nd Sunday - Mother's Day May last Monday - Memorial Day ( Decoration Day , officially May 30) June 14 - Flag Day June 3rd Sunday - Father's Day June 20-22 2nd Quarter Day - Summer Solstice June 21 - Litha (Norse/Anglo-Saxon for ...

Microsymposium 38, MS082, 2003 (A4 format) EVALUATING THE STRUCTURE OF THE SURFACE LAYER OF MERCURY. ... Photometric Analysis of the Lunar Surface Analogue. ... The phase function obtained directly on some segments of the lunar surface: 1- phase function of the Moon, 2 - phase function of Mercury, 3 - phase function of segments, converted to the lunar phase function system (correlation 0.8), 4 - phase function of segments, converted to the Mercurian phase function (correlation 0.9). ...

Space debris is a serious and growing threat to operating spacecraft. Potential debris collisions with satellites are becoming increasingly likely and can cause economic loss of between $25 million and $500 million per event. ... National and international partners include EOS Space Systems, Lockheed Martin Space Systems (US), Optus Satellite Systems, the Australian National University, RMIT University and the National Institute of Information and Communication s Technology (Japan) . ...

... Moon . ... What can astronomers tell us about the different colors on the surface of Jupiter's moon Europa? ... We can use the colors of Europa s surface to tell us about the chemical compounds that make up the surface and subsurface of the jovian moon. Even before the first spacecraft made a close visit to Europa, astronomers on Earth used telescopes to study the moon and were able to use a technique called spectroscopy to determine that Europa s surface is composed mostly of water ice. ...

... Like a last gasp of breath, Sun-like stars puff away their outer layers of gas at the end of their lives. This gas floats away into space and forms beautiful and striking clouds, which are called planetary nebulae (although they have nothing to do with planets). ... Yet, astronomers looking at 100 planetary nebulae in the bulging centre of our Galaxy, the Milky Way have found that most of the bipolar planetary nebulae in this region are acting in the same, strange, way. ...

Selected (two) topical problems in solar / stellar modelling Stellar Astrophysics Centre Improving solar physics by studying other stars GЭnter Houdek The effect of the surface layers on the oscillation frequencies Asteroseismic ages and heavy-element abundances of the Sun solar-like stars Courtesy of J. Christensen-Dalsgaard IAU-GA-SP13 ­ Beijing ­ August 2012 Observed solar frequencies m-averaged frequencies from MDI instrument on SOHO Observed ...

... Bad Astronomy . ... Bitesize Astronomy . ... Keep Bad Astronomy close to your heart, and help make me filthy rich. ... It's semi-common knowledge that stars twinkle and planets don't. By semi-common, I mean that a lot of folks know that, but I also mean it isn't strictly true. Stars twinkle because we see them from the bottom of a sea of air. ... These small bundles of air act like little lenses, bending light as it passes through them. ... What we see is the light from the star flickering. ...

Blackholes Forum Message . Forums: . ... Alternative Idea . ... With the proposal of exotic super dense entities like quark stars and others including black holes, matter on the atomic level can, and most likely does, break down to its most simplist building blocks (photons, leptons, quarks, etc). ... www.astronomy.net . About Astronomy Net | ... Forum posts are Copyright their authors as specified in the heading above the post. "dbHTML," "AstroGuide," "ASTRONOMY.NET" & "VA.NET" . ...

... The expansion is measured as a number called the Hubble Constant . ... Our value is about 20% lower than the one got with the Hubble Space Telescope in 1994," said Dr Jim Lovell, leader of the team that made the measurement. The Hubble Constant is named after American astronomer Edwin Hubble, who in the 1920s found that other galaxies were moving away from ours. ... The Hubble Constant links the galaxy's distance with its speed." ... A short run-down on the Hubble Constant: . ...

Ghost is an Emily Saliers song, written in 1991. The version I'm transcribing is from the Newport Folk Fest of 10 August '91. Ghost There's a letter on the desk top I dug out of a drawer The last truce we ever came to in our adolescent war And I start to feel the fever from the warm air through the screen You come regular like seasons, freely through my dreams And the Mississippi's mighty ...

... When the Voyager 2 spacecraft flew by the planet Uranus in January 1986, astronomers were treated to their first close-up glimpse of the satellites that orbit the seventh planet. ... But by far the most intriguing of those 15 satellites was a jigsaw-puzzle world called Miranda . ... How dark was it at Miranda? One of the Voyager scientists put it this way: Taking pictures in the Uranus system is like trying to do photography in a ballpark at night when the only light comes from a single candle. ...

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. ...

... Armagh Observatory, College Hill, Armagh BT61 9DG, +44 (0)28 3752 2928 . ... Although the comet itself never comes dangerously close to the Earth, the particles of dust that it has shed during its many past passages through perihelion found their way into the Earth's atmosphere, appearing as meteors in the cold December sky. ... Animation 1 . ... An Ursid meteor captured by the Armagh Observatory's NE-facing meteor camera in the early morning of 23rd December. ... Meteor Showers Online . ...

... Transits of Venus . ... Unless medical science invents some way to extend human life well beyond 100 years, the June 5-6, 2012 transit of Venus will likely be the last one anyone alive today will ever see. The next Venus transit won’t take place until December 2117, ¬ 105 years from now. ... ATMoB member Robert Naeye is Editor in Chief of Sky Telescope. ... Copyright (c) Amateur Telescope Makers of Boston, Inc. ...