Terry's Astronomy Thread.

[supermousie]

Re: Terry's Astronomy Thread.

Oh my god Terry that picture is amazing.

[darklordsarumon9]

Re: Terry's Astronomy Thread.

<33

[Bluearrowll]

Re: Terry's Astronomy Thread.

What's in the sky tonight?
June 14, 2012

-Globular star clusters are not all alike. But some do look more similar than others. With the Moon out of the sky, now is a fine time to compare and contrast many of them in your scope.

-Saturn (magnitude +0.6, in Virgo) shines high in the south as twilight fades. Below it by 5° is Spica. Later after dark they move to the southwest.

Astro Picture of the Day:
June 14, 2012

Source:
In 1716, English astronomer Edmond Halley noted, "This is but a little Patch, but it shews itself to the naked Eye, when the Sky is serene and the Moon absent." Of course, M13 is now modestly recognized as the Great Globular Cluster in Hercules, one of the brightest globular star clusters in the northern sky. Telescopic views reveal the spectacular cluster's hundreds of thousands of stars. At a distance of 25,000 light-years, the cluster stars crowd into a region 150 light-years in diameter, but approaching the cluster core upwards of 100 stars could be contained in a cube just 3 light-years on a side. For comparison, the closest star to the Sun is over 4 light-years away. Along with the cluster's dense core, the outer reaches of M13 are highlighted in this sharp color image. The cluster's evolved red and blue giant stars show up in yellowish and blue tints.

[Bluearrowll]

Re: Terry's Astronomy Thread.

What's in the sky tonight?
June 15, 2012

-With summer beginning in just five days, Scorpius is already rearing up in the southeast at nightfall. Its brightest star is orange Antares. The "outrigger" stars of Antares are just below and upper right of it. Farther upper right is the row of stars marking Scorpius's head. This is a grand area to explore with a sky atlas and binoculars.

-As dawn brightens Saturday morning, the Moon, Jupiter, and Venus form a diagonal line above where the Sun will rise, as shown here.

-If you happen to be in a dark area or are pulling an allnighter outside today, you can expect to see a few meteorites blaze through the sky; the Lyrid meteor shower peaks today.

Astro Picture of the Day:
June 15, 2012

Source:
Nearby and bright, spiral galaxies M65 (top) and M66 stand out in this engaging cosmic snapshot. The pair are just 35 million light-years distant and around 100,000 light-years across, about the size of our own spiral Milky Way. While both exhibit prominent dust lanes sweeping along their broad spiral arms, M66 in particular is a striking contrast in red and blue hues; the telltale pinkish glow of hydrogen gas in star forming regions and young blue star clusters. M65 and M66 make up two thirds of the well-known Leo Triplet of galaxies with warps and tidal tails that offer evidence of the group's past close encounters. The larger M66 has been host to four supernovae discovered since 1973.

[Bluearrowll]

Re: Terry's Astronomy Thread.

What's in the sky tonight?
June 16, 2012

-If you're awake in early dawn Sunday morning, look low in the east-northeast for the thin waning crescent Moon close to Jupiter, as shown here. As dawn brightens look for Venus 9° to Jupiter's lower left. Bring binoculars.

Astro Picture of the Day:
June 16, 2012

Source:
Why does this galaxy have such a long tail? In this stunning vista recorded with the Hubble Space Telescope's Advanced Camera for Surveys, distant galaxies form a dramatic backdrop for disrupted spiral galaxy Arp 188, the Tadpole Galaxy. The cosmic tadpole is a mere 420 million light-years distant toward the northern constellation Draco. Its eye-catching tail is about 280 thousand light-years long and features massive, bright blue star clusters. One story goes that a more compact intruder galaxy crossed in front of Arp 188 - from left to right in this view - and was slung around behind the Tadpole by their gravitational attraction. During the close encounter, tidal forces drew out the spiral galaxy's stars, gas, and dust forming the spectacular tail. The intruder galaxy itself, estimated to lie about 300 thousand light-years behind the Tadpole, can be seen through foreground spiral arms at the lower left. Following its terrestrial namesake, the Tadpole Galaxy will likely lose its tail as it grows older, the tail's star clusters forming smaller satellites of the large spiral galaxy.

[Bluearrowll]

Re: Terry's Astronomy Thread.

What's in the sky tonight?
June 17, 2012

-Can you see the big Coma Berenices star cluster? Does your light pollution really hide it, or do you just not know exactly where to look? The cluster is 2/5 of the way from Denebola (Leo's tail) to the end of the Big Dipper's handle (Ursa Major's tail). The cluster is about 5° wide — a big, dim glow in at least a moderately dark sky. Its brightest members form an inverted Y that nearly fills a binocular view.

-Mercury (about magnitude –0.3 and fading) is very low in the west-northwest about 30 or 40 minutes after sundown. Don't confuse it with Capella far to its right, in the northwest. Pollux and Castor are above Mercury early in the week, and to the right of it by June 23rd.

Astro Picture of the Day:
June 17, 2012

Source:
Why does Jupiter have rings? Jupiter's rings were discovered in 1979 by the passing Voyager 1 spacecraft, but their origin was a mystery. Data from the Galileo spacecraft that orbited Jupiter from 1995 to 2003 later confirmed that these rings were created by meteoroid impacts on small nearby moons. As a small meteoroid strikes tiny Adrastea, for example, it will bore into the moon, vaporize, and explode dirt and dust off into a Jovian orbit. Pictured above is an eclipse of the Sun by Jupiter, as viewed from Galileo. Small dust particles high in Jupiter's atmosphere, as well as the dust particles that compose the rings, can be seen by reflected sunlight.

[Bluearrowll]

Re: Terry's Astronomy Thread.

What's in the sky tonight?
June 18, 2012

-Vega is the brightest star on the eastern side of the evening sky. Deneb is the brightest to its lower left. Altair is farther to Vega's lower right. These form the big Summer Triangle.

-This season there's another, temporary "Summer Triangle" toward the southwest: bright Arcturus high on top, the Saturn-Spica pair below it, and Mars off to the pair's right or lower right.

-Venus (magnitude –4.3), after transiting the Sun on June 5th, is now deep in the glow of dawn. Look for it low in the east-northeast before sunrise. Don't confuse Venus with Jupiter to its upper right. The two planets are 9° apart on the morning of June 16th and 6° apart on June 23rd.

-Below or lower right of Venus twinkles much fainter Aldebaran; use binoculars as daybreak brightens. Jupiter and Venus, the two brightest planets, are on their way up for a grand showing in the morning sky this summer.

Astro Picture of the Day:
June 18, 2012

Source:
Why were the statues on Easter Island built? No one is sure. What is sure is that over 800 large stone statues exist there. The Easter Island statues, stand, on the average, over twice as tall as a person and have over 200 times as much mass. Few specifics are known about the history or meaning of the unusual statues, but many believe that they were created about 500 years ago in the images of local leaders of a lost civilization. Pictured above, some of the stone giants were illuminated in 2009 under the central band of our Milky Way Galaxy.

[Bluearrowll]

Re: Terry's Astronomy Thread.

What's in the sky tonight?
June 19, 2012

-This is the time of year when the Little Dipper floats straight upward from Polaris after dark — like a released helium balloon.

-New Moon (exact at 11:02 a.m. EDT).

-Mars (magnitude +0.7, crossing from Leo into Virgo) shines orange in the southwest at dusk and lower in the west as evening grows late. This week Mars creeps to the halfway point from Regulus (off to its lower right) to the Saturn-and-Spica pair (left). Mars will shoot the gap between Saturn and Spica in mid-August. In a telescope Mars is gibbous and tiny, continuing to shrink every week.

Astro Picture of the Day:
June 19, 2012

Source:
During July 22nd's 2009 solar eclipse, the Moon's dark shadow traced a narrow path as it raced eastward across India and China and on into the Pacific. Hong Kong was south of the shadow's path, so a total eclipse was not visible there, but a partial eclipse was still enjoyed by inhabitants of the populous city. And while many were (safely!) watching the sky, images of the partially eclipsed Sun adorned the city itself. In this downlooking photo, taken at 9:40am local time, a remarkable array of solar eclipse views was created by reflection in a grid of eastward facing skyscraper windows. The photographer's location was the 27th floor of Two Pacific Place.

[Bluearrowll]

Re: Terry's Astronomy Thread.

What's in the sky tonight?
June 20, 2012

-This is the longest day and shortest night of the year in the Northern Hemisphere. Summer begins at the solstice: 7:09 p.m. EDT. This is when the Sun reaches its northernmost point in the sky and begins its six-month return southward. In the Southern Hemisphere, winter begins.

-If you have a good view of the west-northwest horizon (from mid-northern latitudes), mark precisely where the Sun sets. In a few days you should be able to detect that it's again starting to set a little south of this point. Build your own Stonehenge?

-Mercury (about magnitude –0.3 and fading) is very low in the west-northwest about 30 or 40 minutes after sundown. Don't confuse it with Capella far to its right, in the northwest. Pollux and Castor are above Mercury early in the week, and to the right of it by June 23rd.

Astro Picture of the Day:
June 20, 2012

Source:
How was this unusual looking galaxy created? No one is sure, especially since spiral galaxy NGC 7049 looks so strange. NGC 7049's striking appearance is primarily due to an unusually prominent dust ring seen mostly in silhouette. The opaque ring is much darker than the din of millions of bright stars glowing behind it. Besides the dark dust, NGC 7049 appears similar to a smooth elliptical galaxy, although featuring surprisingly few globular star clusters. NGC 7049 is pictured above as imaged recently by the Hubble Space Telescope. The bright star near the top of NGC 7049 is an unrelated foreground star in our own Galaxy. Not visible here is an unusual central polar ring of gas circling out of the plane near the galaxy's center. Since NGC 7049 is the brightest galaxy in its cluster of galaxies, its formation might be fostered by several prominent and recent galaxy collisions. NGC 7049 spans about 150 thousand light years and lies about 100 million light years away toward the constellation of Indus.

[Bluearrowll]

Re: Terry's Astronomy Thread.

What's in the sky tonight?
June 21, 2012

-As the glow of sunset fades, look low in the west-northwest for a ragged line of the thin crescent Moon, Mercury, Pollux, and Castor, as shown below.

Astro Picture of the Day:
June 21, 2012

Source:
Made with narrow and broad band filters, this colorful cosmic snap shot covers a field of view about the size of the full Moon within the boundaries of the constellation Cygnus. It highlights the bright edge of a ring-like nebula traced by the glow of ionized hydrogen and oxygen gas. Embedded in the region's interstellar clouds of gas and dust, the complex, glowing arcs are sections of bubbles or shells of material swept up by the wind from Wolf-Rayet star WR 134, brightest star near the center of the frame. Distance estimates put WR 134 about 6,000 light-years away, making the frame over 50 light-years across. Shedding their outer envelopes in powerful stellar winds, massive Wolf-Rayet stars have burned through their nuclear fuel at a prodigious rate and end this final phase of massive star evolution in a spectacular supernova explosion. The stellar winds and final supernovae enrich the interstellar material with heavy elements to be incorporated in future generations of stars.

[Bluearrowll]

Re: Terry's Astronomy Thread.

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

-Spot the crescent Moon in the western twilight this evening, and look far to its right for Mercury, Pollux, and Castor, as shown above. Binoculars help.

-Mercury (about magnitude –0.3 and fading) is very low in the west-northwest about 30 or 40 minutes after sundown. Don't confuse it with Capella far to its right, in the northwest. Pollux and Castor are above Mercury early in the week, and to the right of it by June 23rd.

Astro Picture of the Day:
June 22, 2012

Source:
Grand spiral galaxies often seem to get all the glory, flaunting their young, bright, blue star clusters in beautiful, symmetric spiral arms. But small, irregular galaxies form stars too. In fact dwarf galaxy IC 2574 shows clear evidence of intense star forming activity in its telltale pinkish regions of glowing hydrogen gas. Just as in spiral galaxies, the turbulent star-forming regions in IC 2574 are churned by stellar winds and supernova explosions spewing material into the galaxy's interstellar medium and triggering further star formation. A mere 12 million light-years distant, IC 2574 is part of the M81 group of galaxies, seen toward the northern constellation Ursa Major. Also known as Coddington's Nebula, the lovely island universe is about 50,000 light-years across, discovered by American astronomer Edwin Coddington in 1898.

[Bluearrowll]

Re: Terry's Astronomy Thread.

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

-Look about a fist-width over the Moon for Regulus this evening, as shown above.

-Uranus (magnitude 5.9, at the Pisces-Cetus border) is in the east-southeast before the first light of dawn.

Astro Picture of the Day:
June 23, 2012

Source:
As seen from Frösön island in northern Sweden the Sun did set a day after the summer solstice. From that location below the arctic circle it settled slowly behind the northern horizon. During the sunset's final minute, this remarkable sequence of 7 images follows the distorted edge of the solar disk as it just disappears against a distant tree line, capturing both a green and blue flash. Not a myth even in a land of runes, the colorful but ellusive glints are caused by atmospheric refraction enhanced by long, low, sight lines and strong atmospheric temperature gradients.

[Bluearrowll]

Re: Terry's Astronomy Thread.

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

-The brightest star high in the east these evenings is Vega. The brightest far to its lower right is Altair. Left or lower left of Altair, by a bit more than a fist-width at arm's length, look for the little constellation Delphinus, the leaping Dolphin. Its nose points left.

-Venus (magnitude –4.5) shines low in the east-northeast during dawn. Don't confuse it with Jupiter to its upper right. The two planets remain 5° or 6° apart this week, crossing the background of Aldebaran and the Hyades.

Astro Picture of the Day:
June 24, 2012

Source:
In December of 1972, Apollo 17 astronauts Eugene Cernan and Harrison Schmitt spent about 75 hours on the Moon in the Taurus-Littrow valley, while colleague Ronald Evans orbited overhead. This sharp image was taken by Cernan as he and Schmitt roamed the valley floor. The image shows Schmitt on the left with the lunar rover at the edge of Shorty Crater, near the spot where geologist Schmitt discovered orange lunar soil. The Apollo 17 crew returned with 110 kilograms of rock and soil samples, more than was returned from any of the other lunar landing sites. Now forty years later, Cernan and Schmitt are still the last to walk on the Moon.

[Jerry DB]

Re: Terry's Astronomy Thread.

What's in the sky tonight?
June 24, 2012
Now forty years later, Cernan and Schmitt are still the last to walk on the Moon.

Damn 40 years, longer then I thought. Damn price of getting into orbit is screwing us. It will be cool if we can actually use carbon nanotubes to build a space elevator, shit is going to get crazy in our lifetimes

[Bluearrowll]

Re: Terry's Astronomy Thread.

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

-The Moon shines below distant little Mars during and after dusk.

-Mars (magnitude +0.8, in Virgo) shines orange in the southwest at dusk and lower in the west later. It's still about 25° from the Saturn-and-Spica pair to its left, but it's heading their way! Mars will shoot the gap between them in mid-August.

Astro Picture of the Day:
June 25, 2012

Source:
Sometimes, if you wait long enough for a clear and moonless night, the stars will come out with a vengeance. One such occasion occurred earlier this month at the Piton de l'Eau on Reunion Island. In the foreground, surrounded by bushes and trees, lies a water filled volcanic crater serenely reflecting starlight. A careful inspection near the image center will locate Piton des Neiges, the highest peak on the island, situated several kilometers away. In the background, high above the lake, shines the light of hundreds of stars, most of which are within 100 light years, right in our stellar neighborhood. Far is the distance, arching majestically overhead, is the central band of our home Milky Way Galaxy, shining by the light of millions of stars each located typically thousands of light years away. The astrophotographer reports waiting for nearly two years for the sky and clouds to be just right to get the above shot.