... Tonight's Sky . ... Sky this Month . ... Star Atlas . ... stars . ... The Sky This Week: April 1 - 10 . ... Observing springtime deep-sky objects with a large telescope . ... Why do some stars appear to flash a variety of different colors when you look at them through a telescope? ... So, Earthт??s atmosphere will bend some colors from especially bright stars more so than others, which makes the source look like itт??s flashing colors. Get instant access to subscriber content on Astronomy.com! ...

... 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. ...

Saturation is the primary concern when observing bright targets. The analog-to-digital converter will run out of bit codes at ~28,000 e - pixel -1 in the ATD-GAIN=7 (default) setting, and at ~53,000 e - pixel -1 in the ATD-GAIN=15 setting. ... Hence ATD-GAIN=15 is recommended for targets approaching 28,000 e - pixel -1 . ... For example, stars as bright as V~4.4 can be observed without saturation in F502N using the PC at ATD-GAIN=15 with a 0.11s exposure time. ...

Astronotes Armagh Planetarium's Stellar Blog! ... Space Flight . ... Earth Satellites . ... Leonid meteors seen from 13 km altitude aboard an aircraft during the 1999 Leonids Multi-Instrument Aircraft Campaign (Leonid-MAC). Comet Tempel-Tuttle provides the cometary debris for the Leonid meteor shower. ... Every 17-19 November Earth crosses Tempel-TuttleтАЩs orbit and the Leonids become visible. With clear, dark skies observers may see 10 to 15 Leonid meteors every hour on those mornings. ...

... Mystery flare , from Terry Moseley: . While observing a pass of the ISS tonight (now last night, July 10!) ... It was in the general region of Gamma Ophiuchi, although the sky was too bright, with too few stars visible, for me to get an accurate position. AHA, you'll say - an Iridium Flare! ... BUT - they usually appear in roughly the same quadrant of the sky as the predicted flares, since the Sun-Earth-Satellite angle is similar. ... International Year of Astronomy, Ireland National Node . ...

... Data Reduction FAQ > The reduced science spectrum displayed in the Reflex window appears good but when I try to plot it, it is quite different. How can I get it? ... Observing with ESO Telescopes . ... ESO-MIDAS . ... Reflex . ... ESO Data . ... ESO HST Image Galleries . ... ESO Data Access Policy . ... ESO Science Newsletter . ... ESO Annual Reports . ... Seminars at ESO Santiago . ... Seminars at ESO Garching . ... ESO Telescope Bibliography . ... Last Update: 01.04.14 ESO . ...

home publications > mercury . ... Astronomy Beat . ... Nearly four centuries ago, Galileo's simple observations of Earth's planetary sibling, Venus, buoyed the proponents of a Copernican universe. ... The Italian astronomer had settled into a new house in Florence and had begun to observe Venus, which in November 1610 would have appeared as an evening star, bright in the western sky after dusk. ... From these two observations, Galileo inferred that Venus must orbit closer to the Sun than does Earth. ...

M1 image More About M1 Nice Color Picture . ... M16 image More About M16 HST image . ... M31 image More About M31 Nice Color Picture . ... M42 image ; M43 image More About M42/43 Nice Color CCD Picture . M51 image More About M51 Color Image of M51 M51 Supernova . M57 image More About M57 Nice Color CCD Picture Very Deep M57 Image . ... M81 image More About M81 M81 Supernova Ultraviolet Image of M81 More about Ultraviolet Imaging . M82 image More About M82 M82 False Color M82 True Color . ...

... The TRACE images may be used without restrictions in publications of any kind. ... These two images, taken on 18 November 2000 at 15:54UT and 16:11UT, respectively, show such an event: the red circle in the image to the left shows a region where many loops are cooling, with bright loop tops (the intensity scales with the square root of the image to reduce the dynamic range). ... See also a collection of images related to the Sun, other cool stars, and solar-terrestrial effects . ... Images | ...

... Unexpected Comet Pojmanski Now Visible . ... Comets bright enough to be visible to the unaided eye appear only every few years. Right now, however, a new comet has brightened unexpectedly and is visible as a faint streak to the unaided northern observer in the eastern morning sky just before sunrise. ... The Galaxy Within Centaurus A . ... The bright star.. ... A closer look at the Eagle Nebula, however, shows the bright region is actually a window into the center of a larger dark shell of dust. ...

... Explanations of the Observation codes and GRT codes are available. ... V codes are for AO1 experiments W codes are for AO2 experiments VS experiment codes are VSOP Survey Observations VT Test/Calibration Observations EXPNO SOURCE FRQ Corr DOY DY: DATE UT RANGE #TEL TELESCOPES W071n J0745+10 L Mitk 6 We:Jan-06 10:00 - 17:00 6 UD SH KA AT MP HO W059e J0811+01 C Socr 7 Th:Jan-07 04:00 - 14:00 10 VLBA VS10a J0842+18 C Pent 8 Fr:Jan-08 13:00 - 18:00 6 CD HO UD SH KA MP VS11r J0909+01 C ...

Proposal Identi cation No.: P1015 Date Received: 1997-Feb- 1 00:34:34 Technical Page Proposal Type: Long Term General Category: Pulsars Observation Category: Total Time Requested: 19 Hours Proposal Title: Timing Observations of a New, Bright, Fast Pulsar ABSTRACT: We have discovered a bright 25 ms pulsar, J0407+16, during a drift scan survey at Arecibo Observatory. ... Here we propose further timing observations of this unique pulsar. ... Maybe Part of the observing run. ...

... The following charts/text are intended as tools for monitoring the Type Ia supernovae ( SNe ) event visually or photographically (utilizing telescope equipped CCD equipment).The files include: A replication of The Type Ia SNe , V- magnitude (with data point checks from other cited references)and color index (B-V) templete (to indicate a general color-related trend of the type Ia ... I believe this might help alleviate some of the problems involving the making of acceptable amateur light curves...

... a greenish glow is often seen in the sky, known as the "Northern Lights." ... During magnetic storms, the glow may move southwards, and on occasion it can be seen in much of the US. ... A similar phenomenon is also seen in southern polar regions. ... Auroral light is produced at a height of about 100 km (60 miles) when fast electrons, arriving from space, slam into atoms and molecules of the atmosphere. ... The green light of the aurora puzzled scientists for many years, since it fit no known...

... Observers looking at an object that is moving away from them see light that has a longer wavelength than it had when it was emitted (a redshift), while observers looking at an approaching source see light that is shifted to shorter wavelength (a blueshift). ... By measuring the amount of the shift to the red, we can determine that the bright galaxy is moving away at 3,000 km/sec, which is 1 percent of the speed of light, because its lines are shifted in wavelength by 1 percent to the red. ... Part 2...

ATMoB "Open Cluster Observing Award " Guidelines Purpose: To promote observing among the membership of the Amateur Telescope Makers of Boston through participation in the Open Clusters Observing Awards program. Introduction: This awards program is oriented towards visually observing open clusters above magnitude 9.9. ... It turns out that a very unprejudiced and convenient method to dermine the limiting magnitude is to count the number of visible stars in certain areas on the sky. ...

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Posting Observations . ... You will need to subscribe to vsnet-acc (to allow you access to post your observations). ... VSNet has several different e-mail sigs, and sub sigs. ... These list are controlled by a software package called " Majordomo ", which allows you to subscribe and unsubscribe yourself from these list with an e-mail message (automated). ... Once you have subscribed to vsnet-acc (which will only send you a welcome message back and nothing else) you can post to the other list. ...

Check out the new images (Jan 18-25) and (Jan 26-Feb 05) of the comet by Rob McNaught. ... Every few years a comet becomes bright enough to be easily seen with the naked eye but only every decade or so are these comparable with comets like Halley. ... Before Jan 13, the comet is not visible in the Australian sky after sunset. ... SOHO images . ... On Jan 12 at approximately 09:00 UT (8pm NSW time), comet C/2006 P1 McNaught appears at the 11 o'clock position in the images. ... STEREO images . ...