... 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. ...

... Comet Ikeya-Zhang has become bright enough to stand out in the night sky. ... The comet appears.. ... Known to some as the Elephant's Trunk Nebula, parts of gas and dust clouds of this star formation region may appear to take on foreboding forms, some nearly human. ... This image from the Hubble Space Telescope reveals the Cat's Eye Nebula to be one of the most complex planetary nebulae known. ... In the heart of the Rosette Nebula lies a bright open cluster of stars that lights up the nebula. ...

November 2006 Astronotes 1 Candles in the Dark Image Credit: Wikipedia.org By Colin Johnston, Science Communicator Since the mid-ninteenth century astronomers have used the principle of parallax to measure the distance to other stars. ... How then can we tell, for example, that M31, the galaxy in Andromeda, is 2.2 million light years away? It would be straight-forward to tell how far away a star was if it was exactly the same brightness as our own Sun. ...

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. ...

... To be read in conjunction with Section 4.11 of the WFPC2 Instrument Handbook , -Version 4.0. ... 1 The second study found evidence that CTE loss for faint stars has increased with time (Whitmore, 1998). The primary observational consequence of CTE loss is that a point source at the top of the chip appears to be fainter than if observed at the bottom of the chip, due to the loss of electrons as the star is read out down the chip (see Figure 1 ). ... Last updated: 06/16/98 10:38:00 . ...

... SEARCH ASP SITE: Match ALL words Match ANY word . ... ASP Conference Series . ... Accidental Astrophysics: The Devil's In the Magnitudes, Part II . ... The star second to the Sun in brilliance is Sirius. ... Recall the magnitude system, passed down to us through a hundred generations of sky watchers, as a means of quantifying stellar brightness ("Accidental Astrophysics," May/June, p. 9). ... Yes, it is a magnitude difference, but that difference is due to the distance between us and the star. ...

... STScI-PRC98-11A STARING INTO THE WINDS OF DESTRUCTION: HST/NICMOS IMAGES OF THE PLANETARY NEBULA NGC 7027 The Hubble Space Telescope's Near Infrared Camera and Multi-Object Spectrometer (NICMOS) has captured a glimpse of a brief stage in the burnout of NGC 7027, a medium-mass star like our sun. ... The material settles into a wind of gas and dust blowing away from the dying star. ... During this phase, intense ultraviolet radiation from the central star lights up a region of gas surrounding it. ...

... The HH flow associated with young stellar object HL Tau has an exciting history and even until now the origin of some its features is not clear yet. ... Knotty structures of Herbig-Haro jets are common phenomena and knowing the origin of such structures is essential for understanding the processes of jet formation. ... In the flow detected compact knots with high (-150 km/s) and bow shape structures in front of those, with low radial velocities (-50 km/s). ...

... The Russian TESIS/ CORONAS-PHOTON Solar Observatory, which has been working in orbit since January 30th, 2009, has photographed one of the most important events in the build up to the upcoming solar cycle - the formation of our star's new southern belt of activity. The first magnetic fields of the new cycle in the southern hemisphere appeared on the Sun's surface on May 23-24th. ... The belt of activity is one of the primary concepts, characterizing the solar cycle. ...

... 2015 April 6 . NGC 3293: A Bright Young Star Cluster . ... Open cluster NGC 3293 is located in the constellation Carina , lies at a distance of about 8000 light years , and has a particularly high abundance of these young bright stars. A study of NGC 3293 implies that the blue stars are only about 6 million years old, whereas the cluster's dimmer, redder stars appear to be about 20 million years old. If true, star formation in this open cluster took at least 15 million years. ...

... Since the fast mode window is necessarily small, the source PSF fills much of the window (clearly evident for bright sources). ... As such, the source and background extraction apertures may be truncated by the window. ... While often there will be only one object in the image, one should check for spurious detections which could affect the analysis of the target source and also for missed sources or prominent objects in the window, which may contaminate the target. ...

ATNF Annual Report 2000 (submitted) . ... One of the first products is the HIPASS {\it Bright Galaxy Catalogue}, which is a catalogue of the 1000 apparently brightest HI galaxies in the southern hemisphere. ... In Figure 1 we show the spatial distribution of the brightest HIPASS galaxies. ... Figure 4 shows the velocity distribution of the 1000 brightest HIPASS galaxies (orange) compared to the 1000 brightest optical galaxies (selected from the Lyon/Meudon Extragalactic Database using blue magnitude). ...

... Infrared observations of RCBs show that, even at maximum light, there are copious amounts of dust surrounding the star. ... Therefore the obscuring dust can only cover a fraction of the stellar surface. The picture that emerges (Fig. 2 ) is that at a particular phase in the pulsation cycle, conditions in the photosphere can compel the carbon-rich gas to be expelled from a part of the stellar surface to cool, condense and form dust grains. ...

... We have measured this "redshift" for the pink black holes, and allowed for it in our calculations. ... We see this effect in the emission from gas around these pink black holes, but it is far too small an effect to account for the pinkness. Thus the swirling motions of gas around or into the black holes cannot produc the colour. ... At first we thought that these things were normal blue black holes hidden behind clouds of interstellar dust, that absorbed the blue light and made them appear pink. ...

The Experiment: To find the first galaxies . Understand basic properties of star formation/galaxies ? guess how a young galaxy, or protogalaxy would appear . ... New stars very blue: will appear redder at large distances (redshift). Dust protects gas from radiation. Dust is heated and is luminous at infrared wavelengths. ... Gas in close to a group of galaxies (cluster) may become very hot and emit X-rays. Previous slide . Next slide . Back to first slide . ...

... P2552 Date Received: 2010-Feb-01 16:22:29 Technical Page Proposal Type: General Category: Observation Category: Total Time Requested: Minimum Useful Time: Prop osal Title: ABSTRACT: Regular Pulsars Galactic 18 Hours 30 min Phase-coherent timing of an LMXB-MSP transition ob ject The bright, nearby, eclipsing millisecond pulsar J1023 appears to have had an accretion disk as recently as 2001, making it an important "missing link" in the evolution of low-mass X-ray binaries into radio millisecond...

... For a hundred years, astronomers have been trying to pin down the exact distance to one of our nearest neighbouring galaxies, the Large Magellanic Cloud. ... In the case of the Large Magellanic Cloud, its distance was determined by looking at pairs of stars that orbit each other. ... Finding the accurate distance to the Large Magellanic Cloud is an important breakthrough, because the distance to stars in that galaxy can be used to find the distance to even more remote galaxies. ...

... 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...

Measurement of Sky Brightness at the Iranian National Observatory Davoud Afshari1 and Sadollah Nasiri1,2 1Physics Department, Zanjan University, Zanjan 45195-313, Iran; Institute for Advanced studies in Basic Science (IASBS), Zanjan 45195-1159, Iran; Measurement of light pollution 2 Introduction Among 34 candidate sites at the central part of the country, 5 sites namely Garkesh (in Kashan ), Kolahbarfi(in Kashan ), Deynava (in ... One of these is light pollution. ...

The red colors in this image show the galaxy M66 as it appears at the submillimeter wavelength of 850 microns, while the white background shows the galaxy as it appears in visible light. Regions of cold dust that appear as dark streaks in the white image glow brightly in the red image. ...