... These Frontier Fields will combine the power of HST with the natural gravitational telescopes of high-magnification clusters of galaxies. ... We are soliciting gravitational lensing maps for the last four Hubble Frontier Fields clusters (MACSJ0717.5+3745, MACSJ1149.5+2223, AbellS1063, and Abell 370) based upon the exceptionally deep HST FF imaging and other new ancillary data. ... For the full set of proposal instructions and requirements, see the FY16 Frontier Fields Lensing Map Call for Proposals....

Astronomy Discussion Forums . Forums: . ... Discussion Forums . ... Black Matter . Forum List | ... Post Message | ... Black Matter is composed of all of the light emissions from all of the stars in the universe since stars were first formed, less that amount of light that has been absorbed into stars, planets etc. ... www.astronomy.net . ... Forum posts are Copyright their authors as specified in the heading above the post. "dbHTML," "AstroGuide," "ASTRONOMY.NET" & "VA.NET" . ...

... 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. ...

Next: Elliptical Galaxies. ... NGC 4258 is a nearby ( D = 6.4 Mpc) active spiral galaxy with high luminosity H 2 O maser emission. ... This provides the most compelling evidence so far for a black hole in the centre of a galaxy. ... As NGC 4258, the galaxies NGC 3079, NGC 1068, NGC 4945, and Circinus each host an H 2 0 megamaser (apparent isotropic luminosity > 10 L ). ... Weaker H 2 0 masers are also known in NGC 253, M82 and a few other galaxies (see Greenhill et al. 1990, and references therein). ...

The target is a new candidate qLMXB found in the J1655 field of the ChaMPlane survey. ... Use SDSS u,g,r,i,z to take light curves continuously. 3-5min exposures. ... Skyflats: Take twilight skyflats starting shortly after sunset at around 6:00pm. ... Take the first Ha skyflats with adjusted exposure time (remember to turn the tracking on during exposure and off during readout). ... Take the first I filter skyflat with exposure time equal to 1/10 of the last Ha skyflat exposure. ...

... Science . ... Science Users Information > Science Activities > PhD Thesis Topics offered by ESO Faculty Members > Thesis Topic: How much can a supermassive black hole consume? ... Science Users Information . ... Observing with ESO Telescopes . ... Science Software . ... ESO-MIDAS . ... Data Handling and Products . Quality Control and Data Processing . Data Pipelines and Calibrations . ... Science Data Products Forum . ... ESO Data . ... ESO Data Access Policy . ... ESO Science Newsletter . ...

... Credit Copyright: NASA 's Goddard Space Flight Center , CI Lab Explanation: What happens when a star gets too close to a black hole? ... Although angularly unresolved, variations in high energy light indicate that some of the star became shredded and reformed into a disk swirling around the dark abyss. ... Publications with keywords: black hole - accretion disk . Publications with words: black hole - accretion disk . ... Two Black Holes Merge . When Black Holes Collide . ...

... Calibration and analysis of this observation posed very interesting challenges for the authors, in particular dealing with an exciting new instrument whose on-orbit calibration was not yet well defined. ... Five mosaic positions were observed during five consecutive orbits as well as observations for dark and flat calibration. ... Darks and flats had to be created from contemporaneous reference observations and problems within the calibration process had to be resolved. ...

... 2015 October 28 . Massive Black Hole Shreds Passing Star . Illustration Video Credit: NASA 's Goddard Space Flight Center , CI Lab . Explanation: What happens when a star gets too close to a black hole? Recent observations from Earth-orbiting observatories of an event dubbed ASASSN-14li , in a distant galactic center , appears to be giving one star's harrowing story. ... In the hypothesized scenario envisioned , a jet formed on the spin axis of the black hole. ... About APOD | ...

... V4641 Sgr is known as a detached binary containing a 9 Msol. black hole and an A0 type companion. ... Spectra of V4641 Sgr were taken by us using SAO 1-m telescope between May 23.972 and 24.002 UT (the orbital phase of 0.35), wavelength range 3900-7500A, resolution 8A, S/N~30-40. ... These observations show essential light excess over the quiet light level seen only in the orbital phases between -0.25 and +0.25 with the maximum value of 0.15 mag in the V band at the black hole inferior conjunction. ...

... Not only can the Sun turn night to day, it can transform obscure 1950s jingles into 1990s alternative-rock hits. ... The sun is a mass of incandescent gas, . ... Studying the Sun can tie together subjects across the curriculum. ... Sunspots and prominences--the tongues of hot plasma which shoot off the Sun's surface and arch gracefully back, following the invisible tethers of magnetic field lines--are just two examples of solar volatility. ... The black dots will be easy to see. ...

... This page contains pictures and text to accompany the press release entitled "some black holes are pink", which was presented as part of the Fresh Science event, ScienceNow! ... I first show colour pictures of the pink black holes (and of some blue and yellow ones for comparison. ... If you are having this trouble, I've included pictures below with stretched colour maps, to emphasise the colours: these should print better. (jpeg image, 29kb) . ... Quasar (black hole) PKS 1133-172. ...

... Armagh Observatory, College Hill, Armagh BT61 9DG, +44 (0)28 3752 2928 . ... The adopted fit to the K2 light curve for EQ Psc shown in Fig. ... Black dots are the K2 observations. ... We suggest that this is due to reflection from a cool companion, making EQPsc the longest-period member of some 30 binaries comprising a hot subdwarf and a cool dwarf companion (sdB+dM), and hence useful for exploring the common-envelope ejection mechanism in low-mass binaries. Full paper in PDF format . ...

... Astronomy news . ... NASA's Spitzer Images Out-of-This-World Galaxy . ... It is spiral-shaped like our Milky Way, with long, spindly arms of stars. The "eye" at the center of the galaxy is actually a monstrous black hole surrounded by a ring of stars. In this color-coded infrared view from Spitzer, the area around the invisible black hole is blue and the ring of stars, white. ... The ring around the black hole is bursting with new star formation. ...

... General information . ... Staff . Research staff . ... Information . ... Historical highlights . Historical research . ... This process is thought to occur in circumstellar disks of gas and dust around young stars on rather short timescales : infrared surveys show that the number of low mass stars with disks drops dramatically for stars older than 10 Myr, suggesting that in order to form large solids before the disk disperses, the growth process has to take place within a few million years. ...

... Copyrightї1997 Bob Yen (byen@ix.netcom.com) (http://www.comet-track.com/hb/hb.html) . ... Information on Comet Hale-Bopp for the Non-Astronomer Hale-Bopp rotates about twice a day (3/14/97) . ... The Comet Observation Home Page was been selected to receive the Griffith Observatory Star Award for the week of February 2 - 8, 1997 for excellence in promoting astronomy to the public through the World Wide Web. ... Typically, about 1,000 individual users/computers access this page every day. ...

... 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. ...

... This is called a CalClosed measurement. ... Main targets of the monitoring are i.e. the behaviour of the Charge Transfer Efficiency (CTE), the gain, the effective area or the bad/hot/noisy pixels. The monitoring is performed by combination of calibration observations with an internal radioactive calibration source and observations of astronomical targets. We describe software tools that search for useful internal calibration data and perform the monitoring. ...

... 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. ...

... The spectrograph SP-124 at the Nasmyth-1 focus of the 6 m telescope with UAGS camera and Photometrix CCD PM1024 ( m pixel size) was used for the observations. ... Gratings with 300 and 600 grooves/mm were used, resulting in a spectral resolution of approximately 12 and 6 ? ... A He-Ne-Ar lamp was used for wavelength calibration. ... April 6.914 . ... The reduction of the original two-dimensional CCD data included the standard steps such as bias and dark subtraction, flat-fielding, cosmic-ray removal...