Terry's Astronomy Thread.

[Bluearrowll]

Re: Terry's Astronomy Thread.

What's in the sky tonight?
July 22, 2012

-Arcturus is the brightest star high in the west after dark at this time of year. It and Vega, almost overhead, are the two leading stars of summer. Look off to the right of Arcturus, in the northwest, to spot the Big Dipper.

-Venus and Jupiter (magnitudes –4.6 and –2.1) shine dramatically in the east before and during dawn. They've widened to about 10° or 12° apart now, with Jupiter higher. Look for Aldebaran, much fainter, below or lower right of Jupiter. Also in Jupiter's starry background are the Hyades, and above it are the Pleiades.

Astro Picture of the Day:
July 22, 2012

Source:
How do stars form? A study of star forming region W5 by the sun-orbiting Spitzer Space Telescope provides clear clues by recording that massive stars near the center of empty cavities are older than stars near the edges. A likely reason for this is that the older stars in the center are actually triggering the formation of the younger edge stars. The triggered star formation occurs when hot outflowing gas compresses cooler gas into knots dense enough to gravitationally contract into stars. Spectacular pillars, left slowly evaporating from the hot outflowing gas, provide further visual clues. In the above scientifically-colored infrared image, red indicates heated dust, while white and green indicate particularly dense gas clouds. W5 is also known as IC 1848, and together with IC 1805 form a complex region of star formation popularly dubbed the Heart and Soul Nebulas. The above image highlights a part of W5 spanning about 2,000 light years that is rich in star forming pillars. W5 lies about 6,500 light years away toward the constellation of Cassiopeia.

[Bluearrowll]

Re: Terry's Astronomy Thread.

What's in the sky tonight?
July 23, 2012

-As twilight behind to fade, use the Moon in the west-southwest to guide your way to Saturn, Spica, and Mars glimmering through the dusk (in that order of visibility) as shown below.

-Saturn (magnitude +0.8, in Virgo) shines in the southwest as the stars come out. Below it by 4½° is Spica, nearly the same brightness but twinklier. After dark they move lower to the west-southwest.

Astro Picture of the Day:
July 23, 2012

Source:
While hunting for comets in the skies above 18th century France, astronomer Charles Messier diligently kept a list of the things he encountered that were definitely not comets. This is number 27 on his now famous not-a-comet list. In fact, 21st century astronomers would identify it as a planetary nebula, but it's not a planet either, even though it may appear round and planet-like in a small telescope. Messier 27 (M27) is an excellent example of a gaseous emission nebula created as a sun-like star runs out of nuclear fuel in its core. The nebula forms as the star's outer layers are expelled into space, with a visible glow generated by atoms excited by the dying star's intense but invisible ultraviolet light. Known by the popular name of the Dumbbell Nebula, the beautifully symmetric interstellar gas cloud is over 2.5 light-years across and about 1,200 light-years away in the constellation Vulpecula. This impressive color composite highlights details within the well-studied central region and fainter, seldom imaged features in the nebula's outer halo. It incorporates broad and narrowband images recorded using filters sensitive to emission from sulfur, hydrogen and oxygen atoms. CAn you see the remaining core of the original star that created this nebula in the centre?

[Bluearrowll]

Re: Terry's Astronomy Thread.

What's in the sky tonight?
July 24, 2012

-The waxing Moon this evening forms a quadrangle with Saturn, Spica, and Mars.

-Mars (magnitude +1.0, in Virgo) glows orange low in the west-southwest at dusk, lower right of the Saturn-and-Spica pair by about 13°. It's heading their way; Mars will pass between Saturn and Spica in mid-August. In a telescope Mars is gibbous and very tiny, 6 arcseconds wide.

Astro Picture of the Day:
July 24, 2012

Source:
What's happening over the south pole of Titan? A vortex of haze appears to be forming, although no one is sure why. The above natural-color image shows the light-colored feature. The vortex was found on images taken last month when the robotic Cassini spacecraft flew by the unusual atmosphere-shrouded moon of Saturn. Cassini was only able to see the southern vortex because its orbit around Saturn was recently boosted out of the plane where the rings and moons move. Clues as to what created the enigmatic feature are accumulating, including that Titan's air appears to be sinking in the center and rising around the edges. Winter, however, is slowly descending on the south of Titan, so that the vortex, if it survives, will be plunged into darkness over the next few years.

[Bluearrowll]

Re: Terry's Astronomy Thread.

What's in the sky tonight?
July 25, 2012

-The first-quarter Moon is left of Spica and Saturn this evening, as shown here.

-Uranus (magnitude 5.8, at the Pisces-Cetus border) and Neptune (magnitude 7.8, in Aquarius) are high in the southern sky before the first light of dawn.

Astro Picture of the Day:
July 25, 2012

Source:
Why is this aurora strikingly pink? When photographing picturesque Crater Lake in Oregon, USA last month, the background sky lit up with auroras of unusual colors. Although much is known about the physical mechanisms that create auroras, accurately predicting the occurrence and colors of auroras remains a topic of investigation. Typically, it is known, the lowest auroras appear green. These occur at about 100 kilometers high and involve atmospheric oxygen atoms excited by fast moving plasma from space. The next highest auroras -- at about 200 kilometers up -- appear red, and are also emitted by resettling atmospheric oxygen. Some of the highest auroras visible -- as high as 500 kilometers up -- appear blue, and are caused by sunlight-scattering nitrogen ions. When looking from the ground through different layers of distant auroras, their colors can combine to produce unique and spectacular hues, in this case rare pink hues seen above. As Solar Maximum nears over the next two years, particle explosions from the Sun are sure to continue and likely to create even more memorable nighttime displays.

[Bluearrowll]

Re: Terry's Astronomy Thread.

What's in the sky tonight?
July 26, 2012

-By 10 or 11 p.m. the Great Square of Pegasus is up in the east, balancing on one corner — an early warning of the inevitable approach of fall.

-Saturn (magnitude +0.8, in Virgo) shines in the southwest as the stars come out. Below it by 4½° is Spica, nearly the same brightness but twinklier. After dark they move lower to the west-southwest.

Astro Picture of the Day:
July 26, 2012

Source:
Framing a bright emission region this telescopic view looks out along the plane of our Milky Way Galaxy toward the nebula rich constellation Cygnus the Swan. Popularly called the Tulip Nebula the glowing cloud of interstellar gas and dust is also found in the 1959 catalog by astronomer Stewart Sharpless as Sh2-101. About 8,000 light-years distant the nebula is understandably not the only cosmic cloud to evoke the imagery of flowers. The complex and beautiful nebula is shown here in a composite image that maps emission from ionized sulfur, hydrogen, and oxygen atoms into red, green, and blue colors. Ultraviolet radiation from young, energetic O star HDE 227018 ionizes the atoms and powers the emission from the Tulip Nebula. HDE 227018, is the bright star very near the blue arc at image center.

[Bluearrowll]

Re: Terry's Astronomy Thread.

What's in the sky tonight?
July 27, 2012

-Look left of the Moon (by a fist-width at arm's length or more) for orange Antares. Much closer left of the Moon are the three fainter stars that mark the head of Scorpius, lined up about vertically.

-Mars has crept to within 11° of Saturn and Spica, on its way to passing between them in mid-August.

-Before or during dawn Saturday morning, telescope users near North America's West Coast can see Jupiter's satellites Io and Europa both casting their tiny black shadows onto Jupiter's face from 4:45 to 5:33 a.m. Pacific Daylight Time.

Astro Picture of the Day:
July 27, 2012

Source:
The largest of its kind, the High Energy Stereoscopic System (H.E.S.S.) II telescope stands in the foreground of this photo. Tilted horizontally it reflects the inverted landscape of the Namibian desert in a segmented mirror 24 meters wide and 32 meters tall, equal in area to two tennis courts. Now beginning an exploration of the Universe at extreme energies, H.E.S.S. II saw first light on July 26. Most ground-based telescopes with lenses and mirrors are hindered by the Earth's nurturing, protective atmosphere that blurs images and scatters and absorbs light. But the H.E.S.S. II telescope is a cherenkov telescope, designed to detect gamma rays - photons with over 100 billion times the energy of visible light - and actually requires the atmosphere to operate. As the gamma rays impact the upper atmosphere they produce air showers of high-energy particles. A large camera at the mirror's focus records in detail the brief flashes of optical light, called cherenkov light, created by the air shower particles. The H.E.S.S. II telescope operates in concert with the array of four other 12 meter cherenkov telescopes to provide multiple stereoscopic views of the air showers, relating them to the energies and directions of the incoming cosmic gamma rays.

[Bluearrowll]

Re: Terry's Astronomy Thread.

What's in the sky tonight?
July 28, 2012

-Fiery Antares shines lower right of the waxing gibbous Moon tonight.

-Venus and Jupiter (magnitudes –4.6 and –2.2) shine dramatically in the east before and during dawn, as shown at right. They've widened to about 14° apart now, with Jupiter higher. Look for Aldebaran, much fainter, lower right of Jupiter. Also near Jupiter are the Hyades, and higher above are the Pleiades.

The asteroids Ceres and Vesta, magnitudes 9.1 and 8.4, are in the area too!

Astro Picture of the Day:
July 28, 2012

Source:
Brilliant Venus and bright Jupiter still rise together before dawn. The peaceful waters by a small lakeside house near Stuttgart, Germany reflect their graceful arcing trails in this composited series of exposures, recorded on the morning of July 26. A reflection of planet Earth's rotation on its axis, the concentric trails of these celestial beacons along with trails of stars are punctuated at their ends by a separate final frame in the morning skyview. Easy to pick out, Venus is brightest and near the trees close to the horizon. Jupiter arcs above it, toward the center of the image along with the compact Pleiades star cluster and V-shaped Hyades anchored by bright star Aldebaran. One trail looks wrong, though. Not concentric with the others and so not a reflection of Earth's rotation, the International Space Station streaks off the right side of this scene, glinting in sunlight as it orbits planet Earth.

[Bluearrowll]

Re: Terry's Astronomy Thread.

What's in the sky tonight?
July 29, 2012

-Before and during dawn Monday morning, Jupiter is closest to Aldebaran. They're 4.7° apart, with Aldebaran to Jupiter's lower right.

-Mars and Saturn (magnitudes +1.1 and +0.8, respectively) are low in the west-southwest at dusk. Saturn stands 4½° above similarly-bright Spica. Mars is approaching closer to them every day and will pass between them on August 13th and 14th.

Astro Picture of the Day:
July 29, 2012

Source:
In the center of star-forming region 30 Doradus lies a huge cluster of the largest, hottest, most massive stars known. These stars, known collectively as star cluster R136, were captured above in visible light by the newly installed Wide Field Camera peering though the recently refurbished Hubble Space Telescope. Gas and dust clouds in 30 Doradus, also known as the Tarantula Nebula, have been sculpted into elongated shapes by powerful winds and ultraviolet radiation from these hot cluster stars. The 30 Doradus Nebula lies within a neighboring galaxy known as the Large Magellanic Cloud and is located a mere 170,000 light-years away.

[Bluearrowll]

Re: Terry's Astronomy Thread.

What's in the sky tonight?
July 30, 2012

-The waxing gibbous Moon this evening hangs over the handle of the Sagittarius Teapot.

-Uranus (magnitude 5.8, at the Pisces-Cetus border) and Neptune (magnitude 7.8, in Aquarius) are high in the southern sky before the first light of dawn.

Astro Picture of the Day:
July 30, 2012

Source:
Why did the picturesque 2010 volcanic eruption in Iceland create so much ash? Although the large ash plume was not unparalleled in its abundance, its location was particularly noticeable because it drifted across such well-populated areas. The Eyjafjallajökull volcano in southern Iceland began erupting on 2010 March 20, with a second eruption starting under the center of a small glacier on 2010 April 14. Neither eruption was unusually powerful. The second eruption, however, melted a large amount of glacial ice which then cooled and fragmented lava into gritty glass particles that were carried up with the rising volcanic plume. Pictured above during the second eruption, lightning bolts illuminate ash pouring out of the Eyjafjallajökull volcano.

[MikeShinoda12345]

Re: Terry's Astronomy Thread.

holy crap lol

[ShadowSpawn13]

Re: Terry's Astronomy Thread.

This is probably the best thread I've seen

[Bluearrowll]

Re: Terry's Astronomy Thread.

What's in the sky tonight?
July 31, 2012

-During early dawn Wednesday and Thursday mornings, look low in the east to spot brilliant Venus, magnitude –4.6. Look 2° upper left of it (roughly a finger's width at arm's length) for Zeta Tauri, magnitude 3.0. That's a brightness difference of just over 1,000 times! Binoculars will be necessary as dawn brightens.

-All week, watch Mars move in on Saturn and Spica at dusk.

Astro Picture of the Day:
July 31, 2012

Source:
Why does this Martian rock have so much zinc? Roughly the size and shape of a tilted coffee-table, this oddly flat, light-topped rock outcropping was chanced upon a few weeks ago by the robotic Opportunity rover currently rolling across Mars. Early last month Opportunity reached Endeavour crater, the largest surface feature it has ever encountered, and is now exploring Endeavour's rim for clues about how wet Mars was billions of years ago. Pictured above and named Tisdale 2, the unusual rock structure was probed by Opportunity last week and is now thought to be a remnant thrown off during the impact that created nearby Odyssey crater. The resulting chemical analysis of Tisdale 2, however, has shown it to have a strangely high amount of the element zinc. The reason for this is currently unknown, but might turn out to be a clue to the history of the entire region. Opportunity is already finding rocks older than any previously studied and will continue to explore several other intriguing rock formations only now glimpsed from a distance.

[Bluearrowll]

Re: Terry's Astronomy Thread.

What's in the sky tonight?
August 1, 2012

-Full Moon tonight (exact at 11:27 p.m. EDT). The Moon is in dim Capricornus. Shining high above it is Altair.

-Venus and Jupiter (magnitudes –4.6 and –2.2) shine dramatically in the east before and during dawn, as shown at right. They've widened to about 14° apart now, with Jupiter higher. Look for Aldebaran, much fainter, lower right of Jupiter. Also near Jupiter are the Hyades, and higher above are the Pleiades.

Astro Picture of the Day:
August 1, 2012

Source:
You don't have to be at Monument Valley to see the Milky Way arch across the sky like this -- but it helps. Only at Monument Valley USA would you see a picturesque foreground that includes these iconic rock peaks called buttes. Buttes are composed of hard rock left behind after water has eroded away the surrounding soft rock. In the above image taken about two months ago, the closest butte on the left and the butte to its right are known as the Mittens, while Merrick Butte can be seen just further to the right. High overhead stretches a band of diffuse light that is the central disk of our spiral Milky Way Galaxy. The band of the Milky Way can be spotted by almost anyone on almost any clear night when far enough from a city and surrounding bright lights.

[Bluearrowll]

Re: Terry's Astronomy Thread.

What's in the sky tonight?
August 2, 2012

-Arcturus is the brightest star in the west after dark at this time of year. It and Vega, almost overhead, are the two leading stars of summer. Look off to the right of Arcturus, in the northwest, to spot the Big Dipper dipping down.

Astro Picture of the Day:
August 2, 2012

Source:
No star dips below the horizon and the Sun never climbs above it in this remarkable image of 24 hour long star trails. Showing all the trails as complete circles, such an image could be achieved only from two places on planet Earth. This example was recorded during the course of May 1, 2012, the digital camera in a heated box on the roof of MAPO, the Martin A. Pomerantz Observatory at the South Pole. Directly overhead in the faint constellation Octans is the projection of Earth's rotational axis, the South Celestial Pole, at the center of all the star trail circles. Not so well placed as Polaris and the North Celestial Pole, the star leaving the small but still relatively bright circle around the South Celestial Pole is Beta Hydri. The inverted umbrella structure on the horizon at the right of the allsky field of view is the ground shield for the SPUD telescope. A shimmering apparition of the aurora australis also visited on this 24 hour night.

[MikeShinoda12345]

Re: Terry's Astronomy Thread.

out of curiosity, where do you get all these astro pics?