... NGC 6357s Cathedral to Massive Stars . ... Credit Copyright: NASA , ESA and J. M. Apellюniz ( IAA , Spain) Explanation: How massive can a normal star be? Estimates made from distance, brightness and standard solar models had given one star in the open cluster Pismis 24 over 200 times the mass of our Sun, nearly making it the record holder. ... Publications with keywords: massive stars . Publications with words: massive stars . ... A Massive Star in NGC 6357 . ... Massive Stars Of 30 Doradus . ...

... 2008 October 26 . Massive Stars in Open Cluster Pismis 24 . Credit: NASA , ESA and J. M. ApellАniz ( IAA , Spain) . Explanation: How massive can a normal star be? Estimates made from distance, brightness and standard solar models had given one star in the open cluster Pismis 24 over 200 times the mass of our Sun, making it a record holder. ... Component stars would still remain near 100 solar masses, making them among the more massive stars currently on record. ... About APOD | ...

... 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. ...

... Armagh Observatory, College Hill, Armagh BT61 9DG, +44 (0)28 3752 2928 . See also images taken on November 22nd . Image taken by Andy McCrea who says, . To me the comet appears yellowish and it has gone from star-like to a . ... More images from Andy McCrea here . ... The true explanation is that a very faint comet, known as periodic comet Holmes, produced a massive outburst of material and became a million times brighter than it was just a day earlier. ... More images from Andy McCrea . ...

... Stars . ... Cepheid variable stars have been known since the 18th century. ... Regularly brightening to a peak over days, weeks or months before fading these variable stars were remarkable curiosities to astronomers in past centuries.€а The term Cepheid is taken from the star Delta Cephei in the constellation of Cepheus, which was identified as variable€а in 1784 by the teenaged prodigy John Goodricke (1764-96). ... Tweets that mention Cepheids: Inconstant Stars which break the rules | ...

... Home Observing Brooklyn Museum Plaza . ... Lecture Series 2014-2015 . ... Clear Sky Chart . ... This Month's Sky - 2015 . This Month's Sky - January 2015 . ... This Month's Sky - March 2015 . ... Brooklyn Museum Plaza . ... Beyond New York City . ... Observing Resources for Amateur Astronomers - Part 1: Beginning Observers . ... A History of the First Forty Years of the Amateur Astronomers Association . ... 2016 Amateur Astronomers Association of New York Designed by Press Customizr Powered by . ...

You Can Make Stellar Images Brighter . Articles | ... A few months ago I wrote an article titled "You Can’t Make Them Brighter". So why am I now writing that you can make them brighter. ... The image of a focused star is actually a small disk called the Airy disk, named after the 19 th century scientist Sir George Airy. ... For a given aperture, a smaller Airy disk means that the light is focused to a smaller disk and is therefore brighter. ... www.astronomy.net . About Astronomy Net | ...

... November 5, 1997 . The Milky Way's Gamma-Ray Halo . Credit: D. Dixon ( UCR ), D. Hartmann ( Clemson ), E. Kolaczyk ( U. Chicago ), NASA . Explanation: Our Milky Way galaxy appears to be surrounded by a halo of gamma rays . Gamma rays are the most energetic form of electromagnetic radiation , with more than a hundred thousand times the energy of visible light, but known gamma-ray sources don't account for the diffuse distribution of this high-energy glow. ... About APOD > . ...

Making HST Pictures: Examples and Illustrations . ... These illustrations represent some of the steps and techniques used to produce “pretty pictures” from HST images. ... TIFFs (ftp) . ... Separate images are exposed through different color filters. ... An alternate way to make color images . ... Eight bit (one byte) images contain 256 different values that may be represented by 256 shades of gray or 256 arbitrary colors from a color map (or palette) of all possible colors. ...

... 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. ...

... 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 ...

... Comet Animation . ... Comet structures are diverse and very dynamic, but they all develop a surrounding cloud of diffuse material, called a coma, that usually grows in size and brightness as the comet approaches the Sun. ... As comets approach the Sun they develop enormous tails of luminous material that extend for millions of kilometers from the head, away from the Sun. ... The evaporated molecules boil off and carry small solid particles with them, forming the comet's coma of gas and dust. ...

Clouds of gas between spiral arms . ... In the region of galactic longitudes 60 - 74 degree, latitudes +-15 degree and distances from centres of Galaxy 11 - 12 kpc 81 HI clouds are found and their parameters (figure 1) are measured. ... Average concentration of gas within clouds is 0.15 -3 cm. The life time of the clouds with such concentration between spiral arms permits to evaluate the velocity of ionization and to choose model of heating interstellar matter satisfying to these data. ...

Once students get the hang of it, they can find and measure the brightness of Delta Cephei in a few minutes. ... of Delta Cephei . ... Oct. ... The following table lists the measurements of Delta Cephei made by one amateur astronomer in autumn 1990. ... 4.0 . ... This activity is a simplified version of one that appeared in Hands-On Astrophysics, a series of activities prepared by the American Association of Variable Star Observers with support from the National Science Foundation. << previous page | ...

... Salvage and make safe of 74" . Sidebar Left . Sidebar Top . No Sidebar . Sidebar Bottom . Sidebar Right . Title: Salvage and make safe of 74" . Description: The 74" interior was cleared in the first few months after the fire (images will appear in due course). During September, the debris was cleared, outbuildings demolished and exterior concrete slabs removed. ... Views: 2086 . ... Views: 1849 . ... Views: 1824 . ... Views: 1815 . ... Views: 1812 . ... Views: 1803 . ...

... Astronomers often talk about stars being huge balls of gas, but they contain a lot of dust too. Take a look at this striking new picture of a region in space in which new stars are being born, called the Carina Nebula. ... However, massive stars that are found in the Nebula can help to push more gas and dust particles together. Such massive stars give off strong winds that can blow material together like when leaves or litter gather together in the playground on a windy day. ...

Solar Large-Scale Chains: Some Events . ... The chains appear to light up separators or quasi-separatrix layers between different interacting large-scale magnetic flux systems in the global solar magnetosphere and, in particular, to outline large-scale coronal structures involved in the CME process. ... Some features of the chains and their relations to CMEs are illustrated for a number of halo CME-associated events. 23 events of 1997-2000 . ... Halo-CME-associated events of November 1997 . ...

... The calculator on this page allows you to calculate the H i mass of a gas cloud by specifying either the total H i column density, the total brightness temperature, or the total flux density of the cloud, obtained by summing over all pixels of the map and all spectral channels. ... Warning: The calculator makes use of JavaScript which must be enabled in your webbrowser. ... cm x207B; x00B2; . Sum over all pixels and channels. or . ... Spectral channel width . ... 2016 Tobias Westmeier Contact | ...

... Energy . ... Solar Wind . ... Field . ... 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. For some reason the field slows down the flow of heat from the Sun's interior and keeps sunspots slightly cooler than their surroundings. ... Solar Eclipses . ...

Next: Ejectors in Massive Binary Previous: Artificial Galaxy: Full Matrix . The first version of the Scenario Machine was aimed especially at the simulation of massive binary star evolution. ... First, there is a large class of intermediate mass binaries (say, consisting initially of 8 + 5 solar masses) that can also produce NS and thus lead to the formation of a bright X-ray source. ... Next: Ejectors in Massive Binary Previous: Artificial Galaxy: Full Matrix Mike E. Prokhorov . ...