... Bad Astronomy . ... Bad Astronomy: The North Star, Polaris, is a very bright star. Good Astronomy: Polaris is a middling-bright star, easily missed. ... He said it was close to Polaris, the North Star, but he also said it was in the East. ... It's natural, I suppose, to think that such an important star should be bright, but really, that's a conceit, like thinking that the Earth is at the center of the Universe. If more people knew just why Polaris is the North Star, this Bad Idea would stop. ...

Polaris: The North Star . ... First, Polaris is the nearest bright star to the north spin axis of the Earth. Therefore, as the Earth turns, stars appear to rotate around Polaris , making it the North Star . Since no bright star is near the south spin axis of the Earth, there is currently no South Star . Thousands of years ago, Earth's spin axis pointed in a slightly different direction , and Vega was the North Star. ... NASA Web Site Statements, Warnings, and Disclaimers . ...

... 2005 July 1 . Ring Around Fomalhaut . ... Explanation: Fomalhaut ( sounds like "foam-a-lot") is a bright, young, star, a mere 25 light-year trip from planet Earth in the direction of the constellation Piscis Austrinus . Earlier infrared observations identified a torus of cold material surrounding the nearby star but the panels above detail the sharpest ever visible light-image of Fomalhaut's dusty debris ring, recorded by the Hubble Space Telescope's ACS camera . ... About APOD | ...

... Like the night sky on the Earth, the martian sky hosts a plethora of astronomical phenomena occurring around the clock in a neverending space opera played out for the benefit of robotic and future human observers alike. ... Moons . Mars has two moons, Phobos and Deimos . ... Under the same conditions, Deimos would be as bright as -5, somewhat brighter than the planet Venus appears in Earth's sky. ... The moons are also eclipsed by Mars itself (a situation analogous to lunar eclipses at the Earth). ...

... The Seasons . ... Section #1 Stargazers and Skywatchers described the observed motion of the Sun across the sky, in different seasons of the year. ... If the Earth's axis were perpendicular to the ecliptic, as in the drawings here, the Sun's position in the sky would be halfway between the celestial poles, and its daily path, seen from any point on Earth, would stay exactly the same, day after day. Each point on Earth would be carried around the axis AB once a day. ... The Sun and Seasons . ...

... If the Earth is round, the Sun must be north of the equator in northern summer, and south of the equator in northern winter. ... From the Earth's perspective, the Sun is spiraling from north to south and back again along the ecliptic (see figure 7 ). ... The round Earth, at the summer solstice. ... If the rotation axis of the Earth is tilted with respect to its orbit, the equator bobs back and forth, causing the Sun to be north for half the year, and south for the other half (see figure 9 ). ...

... Now, think about a much bigger move: What do you think it would be like if the Earth moved to a different part of our Galaxy? Our Galaxy, the Milky Way, is shaped like a whirlpool: It has bands of stars that spiral around the centre, which astronomers call the Galaxy s arms . ... We live in the outer parts of the Milky Way, in one of its spiral arms. ... The small centre of the Milky Way is a much more crowded place, as this is where most of its stars are found. ...

... In FOS polarimetry mode the incoming beam was split into orthogonal polarization components by a Wollaston prism behind the entrance aperture. ... As with non-polarimetric observations, no concurrent WAVECAL exposure was routinely taken with polarimetry data, so the limiting accuracies of the default pipeline polarimetry wavelength calibration are the same as for the non-polarimetry case described earlier ( See "Wavelength Calibration" on page 32-49. ...

ATMoB "Double Star Award " Guidelines Purpose: To promote observing among the membership of the Amateur Telescope Makers of Boston ­ in particular, double, triple, and multiple stars. Introduction: Double, triple, and multiple stars are the "Rodney Dangerfields" of the night sky. ... W hile they can be observed under a variety of sky conditions, double stars ­ especially close ones ­ are best viewed on nights when the seeing is steady. ... The direction from a star to Polaris is north. ...

The "ring of fire" seen by satellite cameras around the polar caps (picture below) is probably created by electrons leaking from the tail's plasma sheet, whose magnetic field lines form a somewhat imperfect trap. ... One possible explanation involves the close association between auroral arcs and electric currents which flow along field lines between the ionosphere and distant space ( Birkeland currents ). ... That produces an extra resistance to the flow of current. ...

GALAXIES cenA .tiff 40 Bright Radio Galaxy M31.tiff Nikon Andromeda Galaxy (note HII regions in spiral arms) ngc6744.tiff 40 NGC 6744 a face-on spiral clouds_20d.tiff H'blad The Magellanic Clouds our nearest neighbours Lmc_7.tiff Nikon The Large Magellanic Clouds Lmc_zoom.tiff Nikon Detail of previous image smc_7.tiff Nikon The Small Magellanic Clouds smc-zoom.tiff Nikon Detail of previous image 30dor_40_BVR.tiff 40 The 30 Dor ... B [OIII] Halpha trifid.tiff 40" The Trifid Nebula. ...

... The ancient chronical said about the colour rings around the Sun and the Moon, about three suns in the sky, light columns, bright lightning, different "comets" rushing to the Earth, moving among the stars or round the Earth with the sky. All these occurrences may be divided into three categories: one that occur in the near or far space, processes going on in the Earth atmosphere under the influence of cosmic factors and at last the occurrences connected with the Earth atmosphere. ... Rainbow . ...

... Moon Phase below . ... ARTICLE: Why the moon always shows us the same face . ... Before you continue reading, you should know that this was not always the case, i.e. the Moon once was rotating with respect to the Earth, so that on every night a terrestrial observer (if there was one, because this was long, long before mankind appeared on our planet, and even before any major animals had appeared) saw another face of the Moon. ... Figure 1 (not to scale) shows how we can imagine the system Earth-Moon...

Two major reasons: the number of stars isn't really seven (it's many more), and they all have different brightnesses, so that you see more or fewer of them depending on viewing conditions. The brightness of stars is measured on the magnitude scale, where the most prominent stars in the sky are around 1st magnitude, and the faintest you can see with your eye are about 6th. ... I think this makes it quite likely that the list will be truncated at Taygeta, giving six visible stars. ...

... Press Release Images . Individual Images . ... The right-hand image shows Hubble's close-up view of the galaxy's core, taken in December 1995 by the Wide Field and Planetary Camera 2. The bluish-purple clumps that form the ring are the clusters of infant stars. Two dark, wispy lanes of dust and a pair of blue spiral arms are just outside the star-forming ring. ... The gas is trapped inside the ring through the stars' gravitational attraction. ... Amazing Space | ...

LIPSKIY-RODIONOVA' LUNAR ANTIPODES AS PRECURSORS OF A REGULAR WAVE PLANETOLOGY G.G.Kochemasov IGEM of the Russian Academy of Sciences, Moscow, Russia kochem@igem.ru / Fax: (009)(095)230 21 79 The first observations of the lunar far side allowed to compare it with the near side and draw very important conclusions in the very beginning of planetary studies based on spacecrafts. ... Celestial bodies are dichotomic. ... The concept of celestial bodies includes Sun (a star) as one of them. ...

... Stars . ... By admin March 2, 2012 Posted in: March . ... On a clear night these beautiful, bright stars of the Winter Circle are a joy to behold. ... Moving clockwise the next member of the circle is the brightest star in the night sky, Sirius, the Dog Star, shining at magnitude -1.4 in Canis Major. ... The constellation of Gemini provides two of the stars to the circle.€а The twinsтАЩ heads, Castor and Pollux which at magnitude 1.1 is the 17th brightest in the sky and dimmest in the circle . ...

In ancient times the solar system was thought to be the whole Universe, so the study of planetary motions was cosmology. ... The planets other than the Moon and Sun generally move West to East through the stars, but occasionally stop and move in the opposite direction ( retrograde motion). In order to explain the retrograde motion of the planets, the geocentric model of the Solar System shown above puts the planets on small circles called epicycles . ...

... Our everyday experience of the world around us is . ... An Inquiry-Based Classroom . I n our Everyday Classroom Tools project, we are seeking to immerse elementary school students in the Spirit of Inquiry, to help them begin to observe and learn from their experience. ... What the Everyday Classroom Tools project wishes to stress is that before there were encyclopedias, there were authors, and before there were scientific facts, there were curious people trying to explain the world around them. ...

... More on 51 Peg: . The discovery of a Jupiter--mass planet in orbit around the solar--type star 51Peg has been reported by Michel Mayor and Didier Queloz (Geneva Observatory) on October 6th at the 9th Cambridge workshop on "cool stars, stellar systems, and the sun" held at Florence (Italy). ... Recall that the measurements of radial velocity only yield v sin i which in turn gives us M sin i. For most values of i, sin i will be greater than 0.5 and this gives a mass estimate of 0.5 Jupiter masses. ...