Terry's Astronomy Thread.

[Bluearrowll]

Re: Terry's Astronomy Thread.

What's in the sky tonight?
September 6, 2012

-Whenever Vega is near the zenith, as it is just after dark now, you know Sagittarius is at its highest and best in the south — displaying the deep-sky riches of the summer Milky Way to their best advantage. The Teapot asterism of Sagittarius is tilting to pour to the right. The richest big patch of the Milky Way, the Large Sagittarius Star Cloud, is just above its spout.

Astro Picture of the Day:
September 6, 2012

Source:
In this serene night skyscape, the Milky Way's graceful arc stretches over prominent peaks in the Italian Alps known as Tre Cime di Lavaredo. A 180 degree wide-angle panorama made in four exposures on August 24, the scene does look to the north and the sky is suffused with an eerie greenish light. Still, the subtle glowing bands are not aurorae, but airglow. Unlike aurorae powered by collisions with energetic charged particles and seen at high latitudes, airglow is due to chemiluminescence, the production of light in a chemical reaction, and found around the globe. The chemical energy is provided by the Sun's extreme ultraviolet radiation. Like aurorae, the greenish hue of this airglow does originate at altitudes of 100 kilometers or so dominated by emission from excited oxygen atoms. More easily seen near the horizon, airglow keeps the night sky from ever being completely dark.

[Bluearrowll]

Re: Terry's Astronomy Thread.

What's in the sky tonight?
September 7, 2012

-Jupiter and the last-quarter Moon rise together around 11 or midnight, depending on where you live. Watch for them coming over the east-northeast horizon, and look for fainter Aldebaran to their right. They continue climbing high up the sky until dawn Saturday morning the 8th, as seen here.

Astro Picture of the Day:
September 7, 2012

Source:
South of Antares, in the tail of the nebula-rich constellation Scorpius, lies emission nebula IC 4628. Nearby hot, massive stars, millions of years young, radiate the nebula with invisible ultraviolet light, stripping electrons from atoms. The electrons eventually recombine with the atoms to produce the visible nebular glow, dominated by the red emission of hydrogen. At an estimated distance of 6,000 light-years, the region shown is about 250 light-years across, spanning an area equivalent to four full moons on the sky. The nebula is also cataloged as Gum 56 for Australian astronomer Colin Stanley Gum, but seafood-loving astronomers might know this cosmic cloud as The Prawn Nebula.

[Reincarnate]

Re: Terry's Astronomy Thread.

Googled red sprites a bit more -- those things remind me of Giygas from Earthbound. :O

Super creepy

[Bluearrowll]

Re: Terry's Astronomy Thread.

What's in the sky tonight?
September 8, 2012

-It's still summer, but look low in the southeast this week after about 9 p.m. (depending on where you live) and there's 1st-magnitude Fomalhaut, the Autumn Star, already making its seasonal appearance.

Astro Picture of the Day:
September 8, 2012

Source:
Launched on a grand tour of the outer planets in 1977, by good fortune the twin Voyager spacecraft were also headed in the general direction of the Sun's motion relative to nearby stars. Thirty five years later, Voyager 1 appears to be nearing the boundary of the Sun's heliosphere and interstellar space. Of course the heliosphere is the realm of the Sun defined by the influence of the solar wind and the Sun's magnetic field. But how can you tell when your spacecraft crosses the boundary into interstellar space? One clue would be a sudden increase in the detection of energetic cosmic rays. The high energy particles stream through interstellar space accelerated by distant supernovae in our galaxy, but are normally deflected or slowed by the heliosphere. Covering a 12 month period (September 2011 to 2012), this plot does show a dramatic increase in the rate of cosmic ray particle detection in past months by the Voyager 1 spacecraft. Voyager 1 is now 18 billion kilometers (17 light hours, 122 Astronomical Units) from the Sun and may soon be the first spacecraft from Earth to enter the realm of the stars.

[Bluearrowll]

Re: Terry's Astronomy Thread.

What's in the sky tonight?
September 9, 2012

-This is the time of year when bright Vega shines closest to the zenith as the stars come out at dusk. Vega goes right through your zenith if you're at latitude 39° north (Baltimore, Kansas City, Lake Tahoe).

-Mars and Saturn (magnitudes +1.2 and +0.8) are low in the southwest and west-southwest, respectively, as evening twilight fades. This week they widen from 13° to 17° apart. Look for them well to the lower left of brighter Arcturus in the west. Can you still find Spica twinkling under Saturn? Mars ends the week just 1° below Alpha Librae, a wide binocular double star.

Astro Picture of the Day:
September 9, 2012

Source:
The famous Horsehead Nebula in Orion is not alone. A deep exposure shows that the dark familiar shaped indentation, visible just below center, is part of a vast complex of absorbing dust and glowing gas. To bring out details of the Horsehead's pasture, amateur astronomers at the Star Shadow Remote Observatory in New Mexico, USA fixed a small telescope on the region for over seven hours filtering out all but a very specific color of red light emitted by hydrogen. They then added the image to a full color frame taken over three hours. The resulting spectacular picture details an intricate tapestry of gaseous wisps and dust-laden filaments that were created and sculpted over eons by stellar winds and ancient supernovas. The Horsehead Nebula lies 1,500 light years distant towards the constellation of Orion. Two stars from the Orion's Belt can be found in the above image.

[Wayward Vagabond]

Re: Terry's Astronomy Thread.

this thread reminds me of my astronomy class :') keep it up terry

[Bluearrowll]

Re: Terry's Astronomy Thread.

Today marks the 6 month anniversary of this thread - it was created on March 10. Thank you to all for returning to this page daily and keeping me motivated to do such work first thing in the morning!

What's in the sky tonight?
September 10, 2012

-Equally bright as Vega overhead is Arcturus sinking in the west. Look a third of the way up from Arcturus to Vega for the dim semicircle of Corona Borealis, the Northern Crown, with its one moderately bright star, Alphecca. Look two thirds of the way up for the dim Keystone of Hercules.

-Venus (magnitude –4.3, in Cancer) rises in darkness around 3 a.m. daylight saving time (depending on where you live), emerging above the east-northeast horizon a good two hours before the first glimmer of dawn. By early dawn it's blazing high in the east.

-Binoculars show the Beehive star cluster 4.5° to Venus's lower left on the morning of the 10th, closing to less than 3° to Venus's left by the 12th and 13th.

Astro Picture of the Day:
September 10, 2012

Source:
Curiosity is on the move across Mars -- but where is it going? The car-sized rover's path after 29 Martian days on the surface is shown on the above map. Curiosity is still almost 300 meters from its first major destination, though, a meeting of different types of terrain called Glenelg and visible on the image right. It may take Curiosity two months or so to get to Glenelg as it stops to inspect interesting rocks or landscape features along the way. The above image was taken about one week ago from high up by the HiRise camera onboard the robotic Mars Reconnaissance Orbiter.

[Bluearrowll]

Re: Terry's Astronomy Thread.

What's in the sky tonight?
September 11, 2012

-Before and during dawn Wednesday morning, Venus shines left of the waning crescent Moon, as shown here. They're 4° or 5° apart at the times of dawn for North America. Also spot Procyon farther to their right (outside the frame here). And before the sky brightens too much, binoculars show the Beehive star cluster 3° to Venus's left.

Astro Picture of the Day:
September 11, 2012

Source:
Which part of this picture do you find more interesting -- the land or the sky? Advocates for the land might cite the beauty of the ancient domes of the Bungle Bungle Range in Western Australia. These picturesque domes appear as huge layered beehives and are made of sandstones and conglomerates deposited over 350 million years ago. Advocates for the sky might laud the beauty of the Milky Way's central band shown arching from horizon to horizon. The photogenic Milky Way band formed over 10 billion years ago and now includes many well-known nebulae and bright stars. Fortunately, you don't have to decide and can enjoy both together in this beautiful 8-frame panorama taken from the dark skies of Purnululu National Park about two months ago.

[Bluearrowll]

Re: Terry's Astronomy Thread.

What's in the sky tonight?
September 12, 2012

-Jupiter (magnitude –2.4, in Taurus) rises in the east-northeast around 11 or midnight daylight saving time. Once it's well clear of the horizon, look for fainter orange Aldebaran twinkling 7° to its right, and Beta Tauri a bit farther to Jupiter's left. By dawn this line of three stands very high in the south.

-Uranus (magnitude 5.7, at the Pisces-Cetus border) and Neptune (magnitude 7.8, in Aquarius) reach good heights in the southeast by mid-evening.

Astro Picture of the Day:
September 12, 2012

Source:
M7 is one of the most prominent open clusters of stars on the sky. The cluster, dominated by bright blue stars, can be seen with the naked eye in a dark sky in the tail of the constellation of the Scorpion (Scorpius). M7 contains about 100 stars in total, is about 200 million years old, spans 25 light-years across, and lies about 1000 light-years away. The above deep exposure was taken from Hakos Farm in Namabia. The M7 star cluster has been known since ancient times, being noted by Ptolemy in the year 130 AD. Also visible are a dark dust cloud and literally millions of unrelated stars towards the Galactic center.

[Staiain]

Re: Terry's Astronomy Thread.

Pretty sure I've seen this a few times

[Bluearrowll]

Re: Terry's Astronomy Thread.

Pretty sure I've seen this a few times

Oddly enough, the thing I find most interesting about today's picture is the background stars. If you look closely relative to the position of the cluster, the background stars are actually a high resolution version of the "Milky Way Band". That is, that yellow-white stuff you seem to see in a very dark area is actually billions of stars, and this high resolution photo captures them in the range of the photograph. It's great stuff, really.

[Bluearrowll]

Re: Terry's Astronomy Thread.

What's in the sky tonight?
September 13, 2012

-Venus (magnitude –4.3, in Cancer) rises in darkness around 3 a.m. daylight saving time (depending on where you live), emerging above the east-northeast horizon a good two hours before the first glimmer of dawn. By early dawn it's blazing high in the east.

Binoculars show the Beehive star cluster 6° to Venus's lower left on the morning of the 8th, closing to less than 3° to Venus's left by the 12th and 13th.

Astro Picture of the Day:
September 13, 2012

Source:
In this crowded starfield covering over 2 degrees within the high flying constellation Cygnus, the eye is drawn to the Cocoon Nebula. A compact star forming region, the cosmic Cocoon punctuates a long trail of obscuring interstellar dust clouds. Cataloged as IC 5146, the nebula is nearly 15 light-years wide, located some 4,000 light years away. Like other star forming regions, it stands out in red, glowing, hydrogen gas excited by the young, hot stars and blue, dust-reflected starlight at the edge of an otherwise invisible molecular cloud. In fact, the bright star near the center of this nebula is likely only a few hundred thousand years old, powering the nebular glow as it clears out a cavity in the molecular cloud's star forming dust and gas. But the long dusty filaments that appear dark in this visible light image are themselves hiding stars in the process of formation, seen at infrared wavelengths.

[Bluearrowll]

Re: Terry's Astronomy Thread.

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

-As the Great Square of Pegasus rises high in the east these evenings, the Big Dipper is swinging down low in the northwest as if carrying water. To see the Dipper at its very lowest due north, you'll have to stay up till 2 a.m. daylight-saving time. Come December it'll be there at dusk.

Astro Picture of the Day:
September 14, 2012

Source:
Giant elliptical galaxy M60 and spiral galaxy NGC 4647 do look like an odd couple in this sharp cosmic portrait from the Hubble Space Telescope. But they are found in a region of space where galaxies tend to gather, on the eastern side of the nearby Virgo Galaxy Cluster. About 54 million light-years distant, bright M60's simpler egg-like shape is created by its randomly swarming older stars, while NGC 4647's young blue stars, gas and dust are organized into winding arms rotating in a flattened disk. Spiral NGC 4647 is estimated to be more distant than M60, some 63 million light-years away. Also known as Arp 116, the pair of galaxies may be on the verge of a significant gravitational encounter, though. M60 (aka NGC 4649) is about 120,000 light-years across. The smaller NGC 4647 spans around 90,000 light-years, about the size of our own Milky Way.

[WTFBrandon]

Re: Terry's Astronomy Thread.

wow. so pretty B')
Even cool guys cry.
September 11th is amaaaazing!

[Bluearrowll]

Re: Terry's Astronomy Thread.

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

-With summer nearing its end, the Teapot of Sagittarius has moved over to the south-southwest right after dark, tilting to the right as if to pour out the last of summer.

-New Moon (exact at 10:11 p.m. EDT).

Astro Picture of the Day:
September 15, 2012

Source:
Inspired by the night skies of planet Earth in the International Year of Astronomy, photographer Larry Landolfi created this tantalizing fantasy view. The composited image suggests a luminous Milky Way is the heavenly extension of a country road. Of course, the name for our galaxy, the Milky Way (in Latin, Via Lactea), does refer to its appearance as a milky band or path in the sky. In fact, the word galaxy itself derives from the Greek for milk. Visible on moonless nights from dark sky areas, though not so bright or colorful as in this image, the glowing celestial band is due to the collective light of myriad stars along the plane of our galaxy, too faint to be distinguished individually. The diffuse starlight is cut by dark swaths of obscuring galactic dust clouds. Four hundred years ago, Galileo turned his telescope on the Milky Way and announced it to be "... a congeries of innumerable stars ..."