... Tonight's Sky . ... The Magazine . ... Observing . ... The double star 54 Leonis, spiral galaxy NGC 3198, and emission nebula NGC 3199 . ... Astronomy for Kids . ... Observing springtime deep-sky objects with a large telescope . ... Bright planets meet at dusk . ... Astronomy magazine subscribers can read the full article for free. ... Get instant access to subscriber content on Astronomy.com! ... Receive news, sky-event information, observing tips, and more from Astronomy's weekly email newsletter....

... Landsat 7 Views Planet Earth . ... Spiral disks are loose conglomerations of billions of stars and diffuse gas all gravitationally orbiting a galaxy center. ... Where did all the stars go? ... Here, a high concentration of dust and molecular gas absorb practically all the visible light emitted from background stars. Polar Ring Galaxy NGC 4650A . ... A rare type of galaxy known as a Polar Ring, NGC 4650A is composed of an old central group of stars and a young ring of stars rotating farther out. ...

... Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer. 2008 September 30 . Planets Ahoy! ... Pictured above , the brightest and highest object in the sky is the planet Venus . The object lowest in the sky is the planet Mars , while the object furthest to the left is the planet Mercury . ... Tomorrow's picture: NASA anniversary . ... About APOD | ... A service of: ASD at NASA / GSFC . ...

... Saturn is the sixth planet from the Sun , and the second largest in the solar system . Saturn's most distinctive feature is its ring system . ... Saturn has an internal magnetic field with a dipole aligned with the rotation axis (Ness et al., ... The solar wind and Saturn's rings and satellites supply the particles that are trapped in the radiation belts. ... Between the inner and outer satellites orbits Titan, Saturn's largest moon (larger than the planet Mercury ). ... Res., ...

... Armagh Observatory, College Hill, Armagh BT61 9DG, +44 (0)28 3752 2928 . ... September Perseid meteors captured by the . ... Its occurrence provides astronomers with interesting new data about the hidden trails of meteoroids тАФ small bodies ranging in size from fine dust particles to objects of marble-size and larger тАФ in the solar system and their supposed sources: comets and asteroids passing through the inner solar system. ... The particular comet that created the September Perseids is unknown...

New Moons of Uranus . Brent Gladman's Home Page . ... The discovery of two probable distant satellites of Uranus was reported by B. Gladman, P. Nicholson, J. Burns and J. Kavelaars. ... This discovery was reported in the IAU Circular 6764 . ... Discovery image of S/1997 U 2 . This shows the discovery image of brighter of the two new moons of Uranus. ... This shows the discovery image of faint new moons of Uranus. ... This shows another discovery image of faint new moons of Uranus. ... Uranus . ...

... Solar System . ... Planets . ... Saturn is the sixth planet from the Sun and is the second largest in the solar system. A day on Saturn is 10 hours 39 minutes long, and it takes 29.5 Earth years to revolve about the Sun.€аThe atmosphere is primarily composed of hydrogen with small amounts of helium and methane.€аAt the last count it had 62 Moons, but it is another feature of this gas planet which makes it spectacular, its ring system. ... The first man to notice the rings of Saturn was Galileo. ...

3) Planets and Brown Dwarfs . ... By its nature, this method is most sensitive to massive planets orbiting close to their stars. ... That means that some of the more massive extrasolar planets could actually be brown dwarfs (although the statistics of the finds suggest that most of them are not). ... Another possible difference between brown dwarfs and massive planets is how they are born. ... They would base the fundamental definition on the mode of formation: a planet is built from planetesimals. ...

... Bad Astronomy . ... Bitesize Astronomy . ... Bad Astro Store . ... Slacker Astronomy . ... Keep Bad Astronomy close to your heart, and help make me filthy rich. ... Life Under the Moon . ... Seeing Jupiter's Moons . ... Time Zones and the Spherical Earth . A Companion to the Earth? ... December 19, 1999) . ... Big Moon, Little Moon . ... How Big is the Moon? ... 14, 2000) . ... 2008 Phil Plait. ... Subscribe to the Bad Astronomy Newsletter! Talk about Bad Astronomy on the BA Bulletin Board! ...

. Mars is "behind" the sun from the earth's point of view and is therefore not visible in the nighttime sky (i.e. its up in the daytime). Venus it at greatest elongation and appears in the western sky as a bright object for 2-3 hours after sunset .

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 | ...

Saturn: The beauty of the rings. Saturn . ... Belongs to the giant planets . It has no definite solid surface. ... The free fall acceleration at the Saturn surface near equator is 9,06 m/s^2 . ... In the centre of the planet the temperature is about 20000K. The satellites . ... The rings of Saturn . ... It is proved that Saturn's rings (as well as the other planet's) are the fragments of the great cloud being near the planet with million kilometres length (see how the rings were formed ). ...

... Search . ... Astrophysics Group . Research . ... Research and Instrumentation . ... While this seems an extraordinary endeavour, in light of what we have learnt about Solar System planets, only a handful of key ingredients are required to start characterising an exoplanet. ... The NGTS project is a partnership between the University of Cambridge, Queen?s University Belfast, University of Warwick, University of Leicester, Observatoire de Geneve, DLR (Berlin) and Universidad Catolica de Chile. ...

Now that well over 100 planets have been discovered, we no longer need to ask the question "Are there planets out there?" ... The objective of XO is to find additional hot-Jupiters (like HD 209458b) that transit stars bright enough for detailed follow-up studies to be done with existing telescopes such as HST, Keck, and the VLT. ... Transit observations by themselves provide no information about the mass of the planet and radial velocity studies can yield only minimum masses. ...

I was wondering what conditions should be met to have the "darkest" sky .. ... Upon the above publication of the Southern Galactic hemisphere, TunГ Tezel started seeking opportunities to create the Northern counterpart image. ... So, the initial quest of having the darkest possible sky have delivered us these two all-sky images of the two galactic hemispheres as seen from Planet Earth. Zoomable and 'full-screenable' fisheye view of the "darkest sky" Southern Galactic Hemisphere image. ...

... The Pleiades star cluster, also known as the Seven Sisters and Messier 45, is a conspicuous object in the night sky with a prominent place in ancient mythology . ... The stars in the Pleiades are thought to have formed together around 100 million years ago, making them 1/50th the age of our sun, and they lie some 130 parsecs (425 light years ) away. ... Data for these stars are listed in a table below. ... Yes . ... WEBDA Pleiades cluster data . ... M45: The Pleiades Star Cluster (2007 November 18) ...

OBSERVATIONS OF COORBITAL SATELLITES OF SATURN Emel'yanov N., Varfolomeev M. Sternberg State Astronomical Institute, Moscow, e-mail : emelia@sai.msu.ru Institut de MИcanique CИleste et de Calcul des иphИmИrides, Paris, e-mail : emelia@imcce.fr Abstract. To improve the orbital parameters and masses of coorbital satellites of Saturn, Janus and Epimetheus, new observations of these satellites are necessary. ... IN: Saturn. ... New observations of Saturn's coorbital satellites" - Icarus. ...

... Master . ... Zel'dovich asteroid . ... August 29, 2013: Asteroid (11438) Zeldovich discovered 40 years ago . ... Asteroid (11438) has quite an elongated orbit with a period of 3.25 yr and eccentricity 0.19 (twice that of Mars). ... Asteroid will be located in Cancer constellation at the distance of 1.63 AU from Earth and 2.62 AU from the Sun (near the aphelion of its orbit), with the magnitude being 17.0m. Telescopes of MASTER network will definitely observe asteroid (11438) Zeldovich in early 2014....

ARCSAT ID NUMBER: AS01 DESCRIPTIVE TITLE: Search for Short-Period Planets Orbiting Bright White Dwarfs PI: Brett Morris (UW) OBSERVER(S): Brett Morris (UW), Doug Branton (UW) UNCERTIFIED/UNTRAINED OBSERVERS: Undetermined Pre-MAP students ... In addition, since typical white dwarfs are roughly Earth-sized, the transit of an Earth-sized planet can cause changes in brightness on the order of several tens of percent for durations on the order of one minute (Agol 2011). ...

... An Automated Search for Extrasolar Planet Transits M. G. Hidas, J. K. Webb, M. C. B. Ashley, C. H. Lineweaver University of New South Wales, Sydney 2052 NSW, Australia J. Anderson University of California, Berkeley, USA arXiv:astro-ph/0209388 v1 19 Sep 2002 M. Irwin Institute of Astronomy, Cambridge, UK Abstract. We are setting up a new search for transiting extra-solar planets using the 0.5m Automated Patrol Telescop e at Siding Spring Observatory, Australia. ... 2002; Mayor et al. 2002). ...