_______________________________________________________________
Please vote for the TWO best Astronomy Pictures of the Day (image and text) of May 8-14, 2011.
(Repeated APODs are not included in the poll.)
All titles are clickable and link to the original APOD page.
We ask for your help in choosing an APOW as this helps Jerry and Robert create "
year in APOD images" review lectures, create APOM and
APOY polls that can be used to create a free PDF calendar at year's end, and provides feedback on which images and APODs were relatively well received. You can select two top images for the week.
Thank you!
_______________________________________________________________
<- Previous week's poll
What's that bright orange dot above the large telescope on the right? Even seasoned sky enthusiasts might
ponder the origin of the orange orb seen by
scrolling across
this panoramic image, taken last December. Perhaps identifying known objects will help. To start, on the far left is a diagonal band of light known as
zodiacal light, sunlight reflected off of dust orbiting in the inner Solar System. The bright white spot on the left, just above the horizon, is
Venus, which also glows by reflected sunlight. Rising diagonally from the ground to the right of Venus is the band of our
Milky Way Galaxy. In the image, the band, which usually
stretches dramatically overhead, appears to arch above the elevated
Chilean landscape. Under the Milky Way arch, toward the left, lie both the
Large and Small
Magellanic Cloud galaxies, while toward the right lies the constellation of Orion surrounded by the red ring of
Barnard's Loop. On the ground, each of the four
Very Large Telescopes is busy keeping an eye on the distant universe. The orange spot -- it's the Moon. The image was taken during a
total lunar eclipse when the normally bright full moon turned into a faint
orb tinted orange by the intervening Earth's atmosphere.
Does gravity have a magnetic counterpart? Spin any
electric charge and you get a
magnetic field. Spin any mass and, according to
Einstein, you should get a very slight effect that acts
something like magnetism. This
effect is expected to be so small that it is beyond practical experience and ground laboratory measurement. In a bold attempt to directly measure
gravitomagnetism, NASA
launched in 2004 the
smoothest spheres ever manufactured into space to see
how they spin. These four
spheres, each roughly the size of a
ping-pong ball, are the key to the ultra-precise
gyroscopes at the core of
Gravity Probe B. Last week, after accounting for persistent background signals, the results were
announced -- the
gyroscopes precessed at a rate consistent with the gravitational predictions of Einstein's
General Theory of Relativity. The results, which bolster
existing findings, may have untold long term benefits as well as shorter term benefits such as
better clocks and
global positioning trackers.
Undulating bright ridges and dusty clouds cross
this close-up of the nearby star forming region M8, also known as the
Lagoon Nebula. A sharp, false-color composite of narrow band visible and broad band near-infrared data from the 8-meter
Gemini South Telescope, the entire view spans about 20 light-years through a region of the nebula sometimes called the Southern Cliff. The highly detailed image explores the association of many newborn stars imbedded in the tips of the bright-rimmed clouds and
Herbig-Haro objects. Abundant in star-forming regions, Herbig-Haro objects are produced as powerful jets emitted by young stars in the process of formation heat the
surrounding clouds of gas and dust. The cosmic Lagoon is found some 5,000 light-years away toward constellation
Sagittarius and the center of our Milky Way Galaxy.
A sunlit crescent of
Saturn's moon Enceladus looms above the night side of Saturn in
this dramatic image from the
Cassini spacecraft. Captured on August 13, 2010 looking in a sunward direction during a flyby of the icy moon, the view also traces layers in the upper atmosphere of Saturn scattering sunlight along the planet's bright limb. Closer to the spacecraft than Saturn, Enceladus is a mere 60,000 kilometers from Cassini's camera. The south polar region of the 500 kilometer-diameter moon is illuminated,
including plumes of water vapor and icy particles spraying above the long fissures in the moon's surface. The fissures have been
dubbed tiger stripes. First discovered in Cassini images from 2005, the plumes are strong evidence that liquid water exists near the surface of
surprisingly active Enceladus.
The beautiful
Trifid Nebula is a
cosmic study in colorful contrasts. Also known as M20, it lies about
5,000 light-years away toward the
nebula rich constellation Sagittarius. A star forming region in the plane of our galaxy, the Trifid illustrates three different types of astronomical nebulae; red
emission nebulae dominated by light emitted by hydrogen atoms, blue
reflection nebulae produced by dust reflecting starlight, and
dark nebulae where dense dust clouds appear in silhouette. The bright red emission region, roughly separated into three parts by obscuring, dark dust lanes, lends the Trifid its popular name. In
this well met scene, the red emission is also juxtaposed with the telltale blue haze of reflection nebulae. Pillars and jets sculpted by newborn stars, below and left of the emission nebula's center, appear in Hubble Space Telescope
close-up images of the region. The Trifid Nebula is about 40 light-years across.
At 2nd magnitude, Polaris is far from the brightest star in the night sky. But it is the brightest star at the left of
this well-composed, starry mosaic spanning about 23 degrees across the
northern sky asterism dubbed the Little Dipper. Polaris is famous as the North Pole Star, a friend to
navigators and
astrophotographers alike, but it's not located exactly at the
North Celestial Pole (NCP) either. It's
presently offset from the NCP by 0.7 degrees. Sliding your cursor over the picture will locate Polaris and the NCP as well as other stars of the Little Dipper. The stars are shown with their proper names preceded by their greek alphabet designations within the ancient
constellation Ursa Minor, the Little Bear.
Dust clouds suspended above the plane of our Milky Way Galaxy are also faintly visible throughout the wide field of view.
<- Previous week's poll
[size=200][color=#FF0000]_______________________________________________________________[/color][/size]
Please vote for the TWO best Astronomy Pictures of the Day (image and text) of May 8-14, 2011.
(Repeated APODs are not included in the poll.)
All titles are clickable and link to the original APOD page.
We ask for your help in choosing an APOW as this helps Jerry and Robert create "[url=http://www.youtube.com/watch?v=NAQXYYbBa1s]year in APOD images[/url]" review lectures, create APOM and [url=http://asterisk.apod.com/viewtopic.php?f=29&t=22695&p=141942#p141942]APOY polls[/url] that can be used to create a free PDF calendar at year's end, and provides feedback on which images and APODs were relatively well received. You can select two top images for the week.
Thank you!
[size=200][color=#FF0000]_______________________________________________________________[/color][/size]
[size=110][url=http://asterisk.apod.com/viewtopic.php?f=29&t=23612][color=#4040FF][b]<- Previous week's poll[/b][/color][/url][/size]
[c][url=http://apod.nasa.gov/apod/ap110509.html][size=150][b]Wonder and Mystery above the Very Large Telescopes (2011 May 9)[/b][/size][/url][/c]
[float=left][img2]http://apod.nasa.gov/apod/image/1105/vltsky_beletsky_2198.jpg[/img2][/float]What's that bright orange dot above the large telescope on the right? Even seasoned sky enthusiasts might [url=http://apod.nasa.gov/apod/ap101213.html]ponder[/url] the origin of the orange orb seen by [url=http://blogs.families.com/media/catncompuermouse.jpg]scrolling[/url] across [url=http://www.eso.org/public/images/potw1119a/]this panoramic image[/url], taken last December. Perhaps identifying known objects will help. To start, on the far left is a diagonal band of light known as [url=http://en.wikipedia.org/wiki/Zodiacal_light]zodiacal light[/url], sunlight reflected off of dust orbiting in the inner Solar System. The bright white spot on the left, just above the horizon, is [url=http://apod.nasa.gov/apod/ap101020.html]Venus[/url], which also glows by reflected sunlight. Rising diagonally from the ground to the right of Venus is the band of our [url=http://casswww.ucsd.edu/archive/public/tutorial/MW.html]Milky Way Galaxy[/url]. In the image, the band, which usually [url=http://www.youtube.com/watch?v=Wj8n_95_yNc]stretches dramatically[/url] overhead, appears to arch above the elevated [url=http://en.wikipedia.org/wiki/Chile]Chile[/url]an landscape. Under the Milky Way arch, toward the left, lie both the [url=http://coolcosmos.ipac.caltech.edu/cosmic_classroom/multiwavelength_astronomy/multiwavelength_museum/lmc.html]Large[/url] and Small [url=http://en.wikipedia.org/wiki/Magellanic_Clouds]Magellanic Cloud[/url] galaxies, while toward the right lies the constellation of Orion surrounded by the red ring of [url=http://apod.nasa.gov/apod/ap101023.html]Barnard's Loop[/url]. On the ground, each of the four [url=http://www.eso.org/public/teles-instr/vlt.html]Very Large Telescopes[/url] is busy keeping an eye on the distant universe. The orange spot -- it's the Moon. The image was taken during a [url=http://www.universetoday.com/81716/total-lunar-eclipse-december-21-2010/]total lunar eclipse[/url] when the normally bright full moon turned into a faint [url=http://science.nasa.gov/science-news/science-at-nasa/2008/13feb_lunareclipse/]orb tinted orange[/url] by the intervening Earth's atmosphere.
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[c][url=http://apod.nasa.gov/apod/ap110510.html][size=150][b]Gravity Probe B Confirms the Existence of Gravitomagnetism (2011 May 10)[/b][/size][/url][/c]
[float=left][img2]http://apod.nasa.gov/apod/image/1105/GP-BExpt-with-SV900.jpg[/img2][/float]Does gravity have a magnetic counterpart? Spin any [url=http://Galileo.phys.Virginia.EDU/classes/109N/more_stuff/E&M_Hist.html]electric[/url] charge and you get a [url=http://www-istp.gsfc.nasa.gov/Education/wmfield.html]magnetic field[/url]. Spin any mass and, according to [url=http://apod.nasa.gov/apod/ap000108.html]Einstein[/url], you should get a very slight effect that acts [url=http://en.wikipedia.org/wiki/Frame_dragging]something like magnetism[/url]. This [url=http://science.nasa.gov/science-news/science-at-nasa/2011/04may_epic/]effect[/url] is expected to be so small that it is beyond practical experience and ground laboratory measurement. In a bold attempt to directly measure [url=http://en.wikipedia.org/wiki/Gravitomagnetism]gravitomagnetism[/url], NASA [url=http://www.youtube.com/watch?v=hSr9rBo3pXs]launched[/url] in 2004 the [url=http://einstein.stanford.edu/TECH/technology1.html]smoothest spheres[/url] ever manufactured into space to see [url=http://einstein.stanford.edu/gallery/artwork/slides/GP-B%20Expt-with-SV.jpg]how they spin[/url]. These four [url=http://einstein.stanford.edu/content/pict_gal/gyroscopes/pages/backlit_gyro.htm]sphere[/url]s, each roughly the size of a [url=http://en.wikipedia.org/wiki/Table_tennis#History]ping-pong[/url] ball, are the key to the ultra-precise [url=http://www.howstuffworks.com/gyroscope.htm]gyroscopes[/url] at the core of [url=http://books.nap.edu/html/gpb/summary.html]Gravity Probe B[/url]. Last week, after accounting for persistent background signals, the results were [url=http://www.youtube.com/watch?v=SBiY0Fn1ze4]announced[/url] -- the [url=http://www.youtube.com/watch?v=5nsCjTApzH8]gyroscopes[/url] precessed at a rate consistent with the gravitational predictions of Einstein's [url=http://asterisk.apod.com/viewtopic.php?f=39&t=21763]General Theory of Relativity[/url]. The results, which bolster [url=http://einstein.stanford.edu/content/press_releases/SU/pr-aps-041807.pdf]existing findings[/url], may have untold long term benefits as well as shorter term benefits such as [url=http://science.nasa.gov/headlines/y2002/08apr_atomicclock.htm]better clocks[/url] and [url=http://www.phys.lsu.edu/mog/mog9/node9.html]global positioning[/url] trackers.
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[c][url=http://apod.nasa.gov/apod/ap110511.html][size=150][b]The Southern Cliff in the Lagoon (2011 May 11)[/b][/size][/url][/c]
[float=left][img2]http://apod.nasa.gov/apod/image/1105/M8_rim2geminicrop600.jpg[/img2][/float]Undulating bright ridges and dusty clouds cross [url=http://www.gemini.edu/node/11631]this close-up of the nearby star forming region M8[/url], also known as the [url=http://apod.nasa.gov/apod/ap100805.html]Lagoon Nebula[/url]. A sharp, false-color composite of narrow band visible and broad band near-infrared data from the 8-meter [url=http://apod.nasa.gov/apod/ap060901.html]Gemini South Telescope[/url], the entire view spans about 20 light-years through a region of the nebula sometimes called the Southern Cliff. The highly detailed image explores the association of many newborn stars imbedded in the tips of the bright-rimmed clouds and [url=http://en.wikipedia.org/wiki/Herbig-Haro_object]Herbig-Haro objects[/url]. Abundant in star-forming regions, Herbig-Haro objects are produced as powerful jets emitted by young stars in the process of formation heat the [url=http://apod.nasa.gov/apod/ap100819.html]surrounding clouds of gas and dust[/url]. The cosmic Lagoon is found some 5,000 light-years away toward constellation [url=http://apod.nasa.gov/apod/ap090925.html]Sagittarius and the center[/url] of our Milky Way Galaxy.
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[c][url=http://apod.nasa.gov/apod/ap110512.html][size=150][b]Enceladus Looms (2011 May 12)[/b][/size][/url][/c]
[float=left][img2]http://apod.nasa.gov/apod/image/1105/CassiniPIA12800Enceladus900c.jpg[/img2][/float]A sunlit crescent of [url=http://saturn.jpl.nasa.gov/science/moons/enceladus/]Saturn's moon Enceladus[/url] looms above the night side of Saturn in [url=http://photojournal.jpl.nasa.gov/catalog/PIA12800]this dramatic image[/url] from the [url=http://saturn.jpl.nasa.gov/index.cfm]Cassini spacecraft[/url]. Captured on August 13, 2010 looking in a sunward direction during a flyby of the icy moon, the view also traces layers in the upper atmosphere of Saturn scattering sunlight along the planet's bright limb. Closer to the spacecraft than Saturn, Enceladus is a mere 60,000 kilometers from Cassini's camera. The south polar region of the 500 kilometer-diameter moon is illuminated, [url=http://apod.nasa.gov/apod/ap091124.html]including plumes[/url] of water vapor and icy particles spraying above the long fissures in the moon's surface. The fissures have been [url=http://apod.nasa.gov/apod/ap090628.html]dubbed tiger stripes[/url]. First discovered in Cassini images from 2005, the plumes are strong evidence that liquid water exists near the surface of [url=http://www.ciclops.org/sector6/golf.php]surprisingly[/url] [url=http://saturn.jpl.nasa.gov/news/newsreleases/newsrelease20110420/]active Enceladus[/url].
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[c][url=http://apod.nasa.gov/apod/ap110513.html][size=150][b]A Beautiful Trifid (2011 May 13)[/b][/size][/url][/c]
[float=left][img2]http://apod.nasa.gov/apod/image/1105/ngc6514_gabany_crop900.jpg[/img2][/float]The beautiful [url=http://www.seds.org/messier/m/m020.html]Trifid Nebula[/url] is a [url=http://www.cosmotography.com/images/cosmic_nurseries.html]cosmic study[/url] in colorful contrasts. Also known as M20, it lies about [url=http://www.atlasoftheuniverse.com/5000lys.html]5,000 light-years[/url] away toward the [url=http://www.seds.org/messier/map/Sgr.html]nebula rich[/url] constellation Sagittarius. A star forming region in the plane of our galaxy, the Trifid illustrates three different types of astronomical nebulae; red [url=http://apod.nasa.gov/apod/ap080424.html]emission nebulae[/url] dominated by light emitted by hydrogen atoms, blue [url=http://apod.nasa.gov/apod/ap090521.html]reflection nebulae[/url] produced by dust reflecting starlight, and [url=http://apod.nasa.gov/apod/ap090522.html]dark nebulae[/url] where dense dust clouds appear in silhouette. The bright red emission region, roughly separated into three parts by obscuring, dark dust lanes, lends the Trifid its popular name. In [url=http://www.cosmotography.com/images/small_ngc6514.html]this well met scene[/url], the red emission is also juxtaposed with the telltale blue haze of reflection nebulae. Pillars and jets sculpted by newborn stars, below and left of the emission nebula's center, appear in Hubble Space Telescope [url=http://apod.nasa.gov/apod/ap071226.html]close-up images[/url] of the region. The Trifid Nebula is about 40 light-years across.
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[c][url=http://apod.nasa.gov/apod/ap110514.html][size=150][b]The Little Dipper (2011 May 14)[/b][/size][/url][/c]
[float=left][img2]http://apod.nasa.gov/apod/image/1105/mp_2011-05_LittleDipperAndreo.jpg[/img2][/float][url=http://stars.astro.illinois.edu/sow/polaris.html]At 2nd magnitude, Polaris[/url] is far from the brightest star in the night sky. But it is the brightest star at the left of [url=http://blog.deepskycolors.com/archive/2011/05/12/little-Dipper.html]this well-composed, starry mosaic[/url] spanning about 23 degrees across the [url=http://www.deep-sky.co.uk/asterisms.htm]northern sky asterism[/url] dubbed the Little Dipper. Polaris is famous as the North Pole Star, a friend to [url=http://www.onr.navy.mil/focus/spacesciences/observingsky/constellations4.htm]navigators[/url] and [url=http://blog.deepskycolors.com/archive/2010/11/10/polaris-and-the-North-Celestial-Pole.html]astrophotographers[/url] alike, but it's not located exactly at the [url=http://apod.nasa.gov/apod/ap101224.html]North Celestial Pole[/url] (NCP) either. It's [url=http://stars.astro.illinois.edu/sow/thuban.html]presently[/url] offset from the NCP by 0.7 degrees. Sliding your cursor over the picture will locate Polaris and the NCP as well as other stars of the Little Dipper. The stars are shown with their proper names preceded by their greek alphabet designations within the ancient [url=http://en.wikipedia.org/wiki/Ursa_Minor]constellation Ursa Minor[/url], the Little Bear. [url=http://coolcosmos.ipac.caltech.edu/image_galleries/IRAS/north.html]Dust clouds[/url] suspended above the plane of our Milky Way Galaxy are also faintly visible throughout the wide field of view.
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[size=110][url=http://asterisk.apod.com/viewtopic.php?f=29&t=23612][color=#4040FF][b]<- Previous week's poll[/b][/color][/url][/size]