Free Republic 4th Quarter Fundraising Target: $88,000 Receipts & Pledges to-date: $19,124
21%  
Woo hoo!! And the first 21% is in!! Thank you all very much!! God bless.

Keyword: astronomy

Brevity: Headers | « Text »
  • Astronomy Picture of the Day -- 47 Tuc Near the Small Magellanic Cloud

    12/05/2012 9:44:29 PM PST · by SunkenCiv · 3 replies
    NASA ^ | December 06, 2012 | (see photo credit)
    Explanation: Globular star cluster 47 Tucanae is a jewel of the southern sky. Also known as NGC 104, it roams the halo of our Milky Way Galaxy along with around 200 other globular star clusters. The second brightest globular cluster (after Omega Centauri) as seen from planet Earth, it lies about 13,000 light-years away and can be spotted naked-eye near the Small Magellanic Cloud (SMC) in the constellation of the Toucan. Of course, the SMC is some 210,000 light-years distant, a satellite galaxy of our Milky Way and not physically close to 47 Tuc. Stars on the outskirts of the...
  • Astronomy Picture of the Day -- Plasma Jets from Radio Galaxy Hercules A

    12/05/2012 9:30:09 PM PST · by SunkenCiv · 19 replies
    NASA ^ | December 05, 2012 | (see photo credit)
    Explanation: Why does this galaxy emit such spectacular jets? No one is sure, but it is likely related to an active supermassive black hole at its center. The galaxy at the image center, Hercules A, appears to be a relatively normal elliptical galaxy in visible light. When imaged in radio waves, however, tremendous plasma jets over one million light years long appear. Detailed analyses indicate that the central galaxy, also known as 3C 348, is actually over 1,000 times more massive than our Milky Way Galaxy, and the central black hole is nearly 1,000 times more massive than the black...
  • Astronomy Picture of the Day -- In the Center of Saturn's North Polar Vortex

    12/04/2012 8:30:49 PM PST · by SunkenCiv · 6 replies
    NASA ^ | December 04, 2012 | (see photo credit)
    Explanation: What's happening at the north pole of Saturn? A vortex of strange and complex swirling clouds. The center of this vortex was imaged in unprecedented detail last week by the robotic Cassini spacecraft orbiting Saturn. These clouds lie at the center of the unusual hexagonal cloud system that surrounds the north pole of Saturn. Saturn's north pole precessed into sunlight just a few years ago, with Cassini taking only infrared images of the shadowed region previously. The above image is raw and unprocessed and is being prepared for release in 2013. Several similar images of the region have recently...
  • Astronomy Picture of the Day -- A Quadruple Lunar Halo Over Spain

    12/02/2012 9:17:35 PM PST · by SunkenCiv · 7 replies
    NASA ^ | December 03, 2012 | (see photo credit)
    Explanation: Sometimes falling ice crystals make the atmosphere into a giant lens causing arcs and halos to appear around the Sun or Moon. This past Saturday night was just such a time near Madrid, Spain, where a winter sky displayed not only a bright Moon but as many as four rare lunar halos. The brightest object, near the top of the above image, is the Moon. Light from the Moon refracts through tumbling hexagonal ice crystals into a 22 degree halo seen surrounding the Moon. Elongating the 22 degree arc horizontally is a circumscribed halo caused by column ice crystals....
  • Astronomy Picture of the Day -- The Gegenschein Over Chile

    12/01/2012 9:56:19 PM PST · by SunkenCiv · 6 replies
    NASA ^ | December 02, 2012 | (see photo credit)
    Explanation: Is the night sky darkest in the direction opposite the Sun? No. In fact, a rarely discernable faint glow known as the gegenschein (German for "counter glow") can be seen 180 degrees around from the Sun in an extremely dark sky. The gegenschein is sunlight back-scattered off small interplanetary dust particles. These dust particles are millimeter sized splinters from asteroids and orbit in the ecliptic plane of the planets. Pictured above from 2008 October is one of the more spectacular pictures of the gegenschein yet taken. Here a deep exposure of an extremely dark sky over Paranal Observatory in...
  • Astronomy Picture of the Day -- Northern Mercury

    12/01/2012 10:10:52 AM PST · by SunkenCiv · 13 replies
    NASA ^ | December 01, 2012 | (see photo credit)
    Explanation: Innermost planet Mercurywould probably not be a good location for an interplanetary winter olympics. But new results based on data from the Mercury orbitingMESSENGER spacecraft indicate that it does have substantial water icein permanently shadowed regions within craters near its north pole. The possibility of ice on Mercury has been entertained for years, inspired by the discovery of radar bright, hence highly reflective, regions near the north pole. Highlighted in yellow in this map based on projected MESSENGER images, radar bright regions are seen to correspond with floors and walls of north polar impact craters. Farther from the pole...
  • Astronomy Picture of the Day -- Clouds in Cygnus

    11/30/2012 7:47:55 PM PST · by SunkenCiv · 5 replies
    NASA ^ | November 30, 2012 | (see photo credit)
    Explanation: Cosmic clouds of gas and dust drift across this magnificent mosaic covering a 12x12 degree field within the high flying constellation Cygnus. The collaborative skyscape, a combination of broad and narrow band image data presented in the Hubble palette, is anchored by bright, hot, supergiant star Deneb, below center near the left edge. Alpha star of Cygnus, Deneb, is the top of the Northern Cross asterism and is seen here next to the dark void known as the Northern Coal Sack. Below Deneb are the recognizable North America and Pelican nebulae (NGC 7000 and IC 5070). Another supergiant star,...
  • Astronomy Picture of the Day — Super Moon vs. Micro Moon

    11/30/2012 7:40:02 PM PST · by SunkenCiv · 8 replies
    NASA ^ | November 29, 2012 | (see photo credit)
    Explanation: Did you see the big, bright, beautiful Full Moon Wednesday night? That was actually a Micro Moon! On that night, the smallest Full Moon of 2012 reached its full phase only about 4 hours before apogee, the most distant point from Earth in the Moon's elliptical orbit. Of course, earlier this year on May 6, a Full Super Moon was near perigee, the closest point in its orbit. The relative apparent size of November 28's Micro Moon (right) is compared to the famous May 6 Super Moon in these two panels, matching telescopic images from Bucharest, Romania. The difference...
  • Astronomy Picture of the Day -- Jupiter and Io

    11/28/2012 6:28:42 PM PST · by SunkenCiv · 24 replies
    NASA ^ | November 28, 2012 | (see photo credit)
    Explanation: On December 3 (UT), Jupiter, the solar system's largest planet, will be at opposition, opposite the Sun in planet Earth's sky, shining brightly and rising as the Sun sets. That configuration results in Jupiter's almost annual closest approach to planet Earth. So, near opposition the gas giant offers earthbound telescopes stunning views of its stormy, banded atmosphere and large Galilean moons. For example, this sharp series was recorded on the night of November 16/17 from the island of Sardinia near Dolianova, Italy. North is up in the images that show off Jupiter's famous Great Red Spot, and planet girdling...
  • Astronomy Picture of the Day -- Bright Jupiter in Taurus

    11/27/2012 3:22:35 AM PST · by SunkenCiv · 4 replies
    NASA ^ | November 27, 2012 | (see photo credit)
    Explanation: That bright star you've recently noticed rising just after sunset isn't a star at all. It's Jupiter, the solar system's ruling gas giant. Bright Jupiter is nearing its December 3rd opposition when it will stand in Taurus, opposite the Sun in planet Earth's sky. Clearly outshining yellowish Aldebaran, alpha star of Taurus, Jupiter is centered in this skyview from November 14th, also featuring the Pleiades and Hyades star clusters, familiar celestial sights as the northern hemisphere winter approaches. Sliding your cursor over the image will label the scene and identify two other solar system worlds approaching their opposition in...
  • Astronomy Picture of the Day -- Wisps of the Veil Nebula

    11/26/2012 7:28:18 PM PST · by SunkenCiv · 9 replies
    NASA ^ | November 26, 2012 | (see photo credit)
    Explanation: Wisps like this are all that remain visible of a Milky Way star. About 9,000 years ago that star exploded in a supernova leaving the Veil Nebula, also known as the Cygnus Loop. At the time, the expanding cloud was likely as bright as a crescent Moon, remaining visible for weeks to people living at the dawn of recorded history. Today, the resulting supernova remnant has faded and is now visible only through a small telescope directed toward the constellation of the Swan (Cygnus). The remaining Veil Nebula is physically huge, however, and even though it lies about 1,400...
  • Astronomy Picture of the Day -- Dark Sand Cascades on Mars

    11/26/2012 7:25:19 PM PST · by SunkenCiv · 23 replies
    NASA ^ | November 25, 2012 | (see photo credit)
    Explanation: They might look like trees on Mars, but they're not. Groups of dark brown streaks have been photographed by the Mars Reconnaissance Orbiter on melting pinkish sand dunes covered with light frost. The above image was taken in 2008 April near the North Pole of Mars. At that time, dark sand on the interior of Martian sand dunes became more and more visible as the spring Sun melted the lighter carbon dioxide ice. When occurring near the top of a dune, dark sand may cascade down the dune leaving dark surface streaks -- streaks that might appear at first...
  • Astronomy Picture of the Day -- NGC 1365: Majestic Spiral with Supernova

    11/24/2012 4:51:09 AM PST · by SunkenCiv · 16 replies
    NASA ^ | November 24, 2012 | (see photo credit)
    Explanation: Barred spiral galaxy NGC 1365 is truly a majestic island universe some 200,000 light-years across. Located a mere 60 million light-years away toward the chemical constellation Fornax, NGC 1365 is a dominant member of the well-studied Fornax galaxy cluster. This sharp color image shows intense star forming regions at the ends of the bar and along the spiral arms, and details of dust lanes cutting across the galaxy's bright core. At the core lies a supermassive black hole. Astronomers think NGC 1365's prominent bar plays a crucial role in the galaxy's evolution, drawing gas and dust into a star-forming...
  • Astronomy Picture of the Day -- The Pipe Nebula

    11/23/2012 12:44:51 AM PST · by SunkenCiv · 4 replies
    NASA ^ | November 23, 2012 | (see photo credit)
    Explanation: East of Antares, dark markings sprawl through crowded star fields toward the center of our Milky Way Galaxy. Cataloged in the early 20th century by astronomer E. E. Barnard, the obscuring interstellar dust clouds include B59, B72, B77 and B78, seen in silhouette against the starry background. Here, their combined shape suggests a pipe stem and bowl, and so the dark nebula's popular name is the Pipe Nebula. The deep and expansive view was represents nearly 24 hours of exposure time recorded in very dark skies of the Chilean Atacama desert. It covers a full 10 by 10 degree...
  • Astronomy Picture of the Day -- Night of the Long Leonid

    11/23/2012 12:40:23 AM PST · by SunkenCiv · 10 replies
    NASA ^ | November 22, 2012 | (see photo credit)
    Explanation: A cosmic grain of sand left the long and colorful trail across this all-sky view. Its grazing impact with planet Earth's atmosphere began at 71 kilometers per second. With the Milky Way stretching from horizon to horizon, the scene was captured on the night of November 17 from the astronomically popular high plateau at Champ du Feu in Alsace, France. Of course, the earthgrazer meteor belongs to this month's Leonid meteor shower, produced as our fair planet annually sweeps through dust from the tail of periodic Comet Tempel-Tuttle. The shower's radiant point in the constellation Leo is very close...
  • Astronomy Picture of the Day -- Diamond Ring and Shadow Bands

    11/21/2012 4:13:51 AM PST · by SunkenCiv · 2 replies
    NASA ^ | November 21, 2012 | (see photo credit)
    Explanation: As the total phase of last week's solar eclipse came to an end, sunlight streaming past the edge of the Moon created the fleeting appearance of a glistening diamond ring in the sky. And while most eclipse watchers did not consider clouds a welcome sight, a view through thin clouds north of Cairns in Queensland, Australia also revealed these remarkable flickering shadow bands. Projected onto the cloud layer, the bands are parallel to the sliver of emerging sunlight. Caused by turbulence in Earth's atmosphere refracting the sliver of sunlight, the narrow bands were captured in this brief, 1/1000th second...
  • Mars Mystery: What HAS Curiosity Discovered?

    11/20/2012 1:45:34 PM PST · by Red Badger · 90 replies
    Discovery.com ^ | Tue Nov 20, 2012 02:13 PM ET | Analysis by Ian O'Neill
    Science isn't something that just happens overnight. It takes many measurements, oodles of analysis, re-testing and re-analysis before any groundbreaking announcement can be made. So, on the surface of Mars, inside Gale Crater on a plain called Aeolis Palus, our tenacious six-wheeled Mars Science Laboratory (MSL) is doing cutting-edge laboratory work on an alien world and mission scientists are itching to announce a "historic" discovery. "This data is gonna be one for the history books. It's looking really good," John Grotzinger, lead scientist of the MSL mission, said in an interview with NPR. But what is he referring to and...
  • Lonely planet: Orphan world spotted in deep space

    11/20/2012 6:33:42 AM PST · by Red Badger · 18 replies
    Space Daily ^ | 14 NOV 2012 | by Staff Writers
    Astronomers on Wednesday reported they had detected a planet that had strayed from its star system and was wandering alone in deep space. Object CFBDSIR2149 is believed to be a cold, young world that for unknown reasons has pulled free of the gravitational pull of its mother star, the European Southern Observatory (ESO) said. It is not the first time that a "free-floating" planet has been found, but this one is the closest that has ever been spotted, at over 100 light years from Earth. Initial observations sketched the object as either a homeless planet or a tiny failed star...
  • Astronomy Picture of the Day -- A Halo Around the Moon

    11/20/2012 3:27:14 AM PST · by SunkenCiv · 20 replies
    NASA ^ | November 20, 2012 | (see photo credit)
    Explanation: Have you ever seen a halo around the Moon? This fairly common sight occurs when high thin clouds containing millions of tiny ice crystals cover much of the sky. Each ice crystal acts like a miniature lens. Because most of the crystals have a similar elongated hexagonal shape, light entering one crystal face and exiting through the opposing face refracts 22 degrees, which corresponds to the radius of the Moon Halo. A similar Sun Halo may be visible during the day. The setting of the above picture is Athens San Sebastian, Greece. The distant planet Jupiter appears by chance...
  • Astronomy Picture of the Day -- Leonids Over Monument Valley

    11/19/2012 3:41:20 AM PST · by SunkenCiv · 5 replies
    NASA ^ | November 19, 2012 | (see photo credit)
    Explanation: What's happening in the sky over Monument Valley? A meteor shower. Over the past weekend the Leonid meteor shower has been peaking. The image -- actually a composite of six exposures of about 30 seconds each -- was taken in 2001, a year when there was a much more active Leonids shower. At that time, Earth was moving through a particularly dense swarm of sand-sized debris from Comet Tempel-Tuttle, so that meteor rates approached one visible streak per second. The meteors appear parallel because they all fall to Earth from the meteor shower radiant -- a point on the...