... 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. ...

Lightning Captured at 7207 Images per Second . ... Credit Copyright: Tom A. Warner , ZTResearch , www.weathervideoHD.TV Explanation: How fast is lightning? ... The above lightning stroke did not move too fast, however, for this extremely high time resolution video to resolve. ... The above lightning bolt starts with many simultaneously creating ionized channels branching out from an negatively charged pool of electrons and ions that has somehow been created by drafts and collisions in a rain cloud . ...

... Data was taken with lbw and the mock spectrometers on 05may09 to investigate the problem with higher time resolution and bandwidth. ... 6 172 Mhz bands were taken centered at: 1200,1300,1400,1500,1600, and 1700 Mhz. 8192 channels (20Khz resolution) was used for the low time resolution (.1 second dumps). 4096 channels (40Khz resolution) was used for the high time resolution (.001 second dumps). ... The total power was computed for each 172 Mhz band and then plotted vs time (.1 second resolution). ...

... Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. 2013 October 14 . High Noon Analemma Over Azerbaijan . Image Credit Copyright: Tun Tezel ( TWAN ) . Explanation: Is the Sun always straight up at noontime? ... Pictured above is one such high noon analemma -- a series of pictures always taken at exactly noontime over the course of a year. ... About APOD | ...

The Doppler shift is the effect of sound increasing or decreasing in pitch as an object moves towards or away from you. ... Light works the same way, except light is shifted to redder colours when an object is moving away, and to blue colours when an object is travelling towards us. ... Almost every object he observed had its light stretched to redder colours, indicating essentially everything in the Universe was moving away from us. ... So the Hubble constant tells us how old the Universe is. ...

... Instead, new evidence obtained using the UK's Infrared Telescope (UKIRT) in Hawaii, spins a different story. Streams of spinning bullets have been discovered. These infrared bullets, moving at prodigious speeds, deposit the spin far away from the birth region'' , stated Armagh Observatory astronomer Dr. Michael Smith. ... Now, using the UK Infrared telescope in Hawaii fitted with sensitive instruments, a team of astronomers have found evidence that the jets of bullets are spinning. ...

... In the US and in other mid-latitude countries north of the equator (e.g those of Europe), the sun's daily trip (as it appears to us) is an arc across the southern sky. ... Moss avoids direct sunlight, and with the sun's path curving across the southern sky, the north side of a tree-trunk is the one most shaded. ... In addition, they are invariably tilted at an angle around 450, to make sure that the arrival of the sun's rays is as close to perpendicular as possible. ...

EMBARGOED UNTIL: 9:20 AM CST, January 6, 1999 CONTACT: John Biretta Space Telecsope Science Institute, Baltimore, MD (Phone: (410) 338-4917; Internet: biretta@stsci.edu) HUBBLE DETECTS FASTER-THAN-LIGHT MOTION IN GALAXY M87 Astronomers reported today discovering clouds which appear to move many times faster than the speed of light, shooting out from the region of a black hole at the center of the M87 galaxy. ... It's an illusion created by the finite speed of light and rapid motion," Biretta said. ...

... About 10% of the time is allocated to moving the telescope to the zenith and exchanging the spectrographic cartridges. ... Focus telescope (open-loop)* . ... TOTAL TIME (seconds) . ... This assumes two 60 second arc exposures and two 55 second readouts. ... Otherwise, the arc exposure will likely consist of a 30 second integration followed by a quick 28 second readout, half the normal time. ... The flat-field exposure can be read out with a quick 28 second readout, half the normal time. ...

An introduction to the celestial sphere, describing its . apparent rotation and the special role of the pole star. ... This lesson plan supplements the web page listed below. Originally named "The sky above us" , it was split into two parts, each of which now has a lesson plan. ... Celestial sphere, constellation, zodiac, celestial pole, the Pole Star ("Polaris"), celestial equator, rotation of the Earth, planets [theodolite, equatorial axis]. ... What makes the Pole Star special? ...

... For instance, motion event handlers are passed a pointer to a GdkEventMotion structure which looks (in part) like: struct _GdkEventMotion { GdkEventType type; GdkWindow *window; guint32 time; gdouble x; gdouble y; ... guint state; ... }; . ... The second field specifies the events we are interested in. ... The "motion_notify_event" and "button_press_event" handlers are pretty simple: static gint button_press_event (GtkWidget *widget, GdkEventButton *event) { if (event->button == 1 && pixmap != ...

... First of all, I should say that you cannot guarantee user-mode processes to have exact control of timing because of the multi-tasking nature of Linux. ... However, for most applications using I/O ports, this does not really matter. To minimise this, you may want to nice your process to a high-priority value (see the nice(2) manual page) or use real-time scheduling (see below). ... Linux 2.x kernels have soft real time support; see the manual page for sched_setscheduler(2) for details. ...

... Crossed Dipoles for dual polarization conducting plane Droopy Dipoles for broad-band, dual polarization LOFAR -Low Band dipole element 4x4 array of dipoles on ground plane - the ` LOFAR -High band' element h s s (many analogies to gratings for optical wavelengths) 4x4 Tuned for 150 MHz sin projection ZA = 0 deg 45 15 60 30 75 4x4 Patterns · · ZA = 30 deg tuned for 150 MHz 120 150 180 210 240 Lofar stations ??? a ` station ' = 101 ` ...

Galaxies are diffuse objects which are imaged against a background of finite brightness and noise. Galaxies which have the maximum contrast with respect to this background are the ones that are first discovered. ... These galaxies have been missed to date but active surveys for them are underway. ... In this page we present several examples of these newly discovered Low Surface Brightness galaxies as well as examples of high surface brightness galaxies. ...

... Pre-university education . ... Samara region . SSAU History . SSAU roadmap . ... Samara State Aerospace University improved its position in the third annual ranking of higher education institutions in Russia. ... Besides Samara State Aerospace University entered the top twenty of the national higher education institutions, as their graduates are in demand by employers. ... Samara State Medical University also rose from the 57th to the 49th place in the ranking of higher education institutions. ...

... A rough estimation is that in the United States there is one planetarium per 100,000 population, ranging in size from the Hayden Planetarium's 20-meter dome seating 430 people, to three-meter inflatable portable domes where children sit on the floor. ... Together dblo associates make a huge impact in the architecture, interior design and development arena in London. ... With the holidays around the corner what better way to spoil your family than with your very own private home cinema. ...

. Pulkovo Observatory of Russian Academy of Sciences is situated . near Saint-Petersburg. It was founded in 1839. 196140, Saint-Petersburg, Pulkovskoye chaussee 65/1 . English version . Russian version . This page has been accessed times since May 1, 1999.

... A new IRAF task has been developed that automatically identifies linear (line-like) features in an image or set of images. ... In order to automatically detect linear features, the first step is to select pixels in the image (Fig. 1 , left panel) that fall within a given data value range. ... Another aspect of extended linear features is that the image space pixels that describe them are in some way adjacent to one another and have a minimum and maximum length. ...

... Tonight's Sky . ... Observing . ... Sky this Month . ... Astronomy for Kids . ... Can you explain Mercury's retrograde motion? Do other planets appear to do this also? ... When astronomers talk about retrograde motion, generally they refer to the apparent motion outer planets make as Earth passes them while orbiting the Sun. ... Get instant access to subscriber content on Astronomy.com! ... Receive news, sky-event information, observing tips, and more from Astronomy's weekly email newsletter. ...