Astronomy Picture of the Day . THEMIS of Mars . ... An energetic jet from the core of giant elliptical galaxy M87 stretches outward for 5,000 light-years. ... Halloween and the Ghost Head Nebula . ... With our modern calendar, however, the real cross-quarter day will occur next week. ... Spinning Black Holes and MCG 6 30 15 . ... If so, this would be the first observational indication that it is possible to make a black hole act like a battery -- and tap into its rotational energy. ...

... Galaxy Cluster in the Early Universe . ... Explanation: Long before medieval alchemists dreamed of transmuting base metals to gold , stellar furnaces in this massive cluster of galaxies - cataloged as RDCS 1252.9-2927 - had transformed light elements into heavy ones . ... The cluster elemental abundances are consistent with the idea that most heavy elements were synthesized early on by massive stars, but current theories suggest that such a massive cluster should be rare in the early Universe . ...

... 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. ...

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. ...

... self-absorption - the absorption of light shining on an object by a process similar to that which produced the light originally; if a cloud emits less light than it absorbs from other clouds behind it, this net loss of light, termed self-absorption , causes the foreground cloud to appear darker than the background field (the term is from spectroscopy, where small absorption dips sometimes occur in larger emission lines, making the latter look as if it is absorbing part of itself) . ... HISA Main ...

Astronomers have found a radio pulsar with a companion at least 11 times the mass of the Sun - the most massive pulsar companion known. The identity of the companion is uncertain: it may be a massive late-type (red) star, a massive but compact blue star, or possibly a black hole. ... The probability of this late-type star being there by chance, and not being the pulsar companion, is only about 1.3%," says team member Dr. Fernando Camilo of Columbia University. ... So what can the companion be? ...

... Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. 2000 February 13 . Southwest Mercury . Credit: Mariner 10 , NASA . Explanation: The planet Mercury resembles a moon. ... In fact, the Earth is the only planet more dense. ... From Earth , Mercury's proximity to the Sun cause it to be visible only for a short time just after sunset or just before sunrise. ... About APOD | ...

... Armagh Observatory, College Hill, Armagh BT61 9DG, +44 (0)28 3752 2928 . An artistтАЩs impression of the binary UZ For and planet . ... A team of astronomers, including Dr Gavin Ramsay of the Armagh Observatory, has found evidence that suggests the existence of an extraordinary planetary system. Two giant planets appear to be revolving at some distance around a compact, interacting stellar binary known as UZ For, which comprises two small stars orbiting very closely one about the other. ...

. Computer Ephemeris. Elements of osculating planetary orbits. Explanations. Each row contains at 0h of Time Dynamical Terrestrial of specified date in system of mean equator and ecliptic J2000.0 the ecliptic osculating elements of heliocentric orbit: inclination of orbital plane (degrees), longitude of ascending node (degrees), argument of perigelion (degrees), semimajor axis (astronomical units), mean motion (degrees per day), eccentricity (dimensionless), mean anomaly (degrees).

To appear in "Fourth Workshop on Robotic Autonomous Observatories (2015)"RevMexAA(SC) MASSIVE PHOTOMETRY OF LOW-ALTITUDE ARTIFICIAL SATELLITES ON MINI-MEGATORTORA S. Karpov, 1, 3 E. Katkova,2 G. Beskin, 1, 3 A. Biryukov3,4 S. Bondar,2 E. Davydov5 E. Ivanov,2 A. Perkov,2 V. Sasyuk3 RESUMEN Favor de prop orcionar un resumen en espanol. ... The nine-channel Mini-MegaTORTORA (MMT-9) optical widefield monitoring system with high temporal resolution system is in operation since June 2014. ...

In the Table below the masses of some asteroids which were determined during the last years are listed. ... The listed values were determined from observations of many test bodies by the weighted least square fit for one perturbing mass and corrections to the orbit elements of all used test bodies. ... based on the observations of 98 asteroids (including 50278) with the values of standard error of mass determination less than 3.0 10 -11 M Sun . ... Mass . ... 3) Mass 121 : 0.74 x 10 -11 M Sun ; . ...

... Tonight's Sky . ... The Magazine . ... Observing . ... The double star 54 Leonis, spiral galaxy NGC 3198, and emission nebula NGC 3199 . ... What