Saturday, April 30, 2016

The Expanding Universe Nova HD 1080p





Another amazing Crop Circles video it will set you free Crossover From ...





UFO SIGHTINGS - ALIENS - The U.S. and ETs by Maurice Osborn





Wednesday, April 27, 2016

M16: Pillars of Star Creation

M16: Pillars of Star Creation:

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2016 April 24


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M16: Pillars of Star Creation

Image Credit: J. Hester, P. Scowen (ASU), HST, NASA


Explanation: Newborn stars are forming in the Eagle Nebula. This image, taken with the Hubble Space Telescope in 1995, shows evaporating gaseous globules (EGGs) emerging from pillars of molecular hydrogen gas and dust. The giant pillars are light years in length and are so dense that interior gas contracts gravitationally to form stars. At each pillars' end, the intense radiation of bright young stars causes low density material to boil away, leaving stellar nurseries of dense EGGs exposed. The Eagle Nebula, associated with the open star cluster M16, lies about 7000 light years away. The pillars of creation were imaged again in 2007 by the orbiting Spitzer Space Telescope in infrared light, leading to the conjecture that the pillars may already have been destroyed by a local supernova, but light from that event has yet to reach the Earth.

Be Honest: Have you seen this image before?

Tomorrow's picture: Strands of Star Death



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Simeis 147: Supernova Remnant

Simeis 147: Supernova Remnant:

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2016 April 25


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Explanation: It's easy to get lost following the intricate strands of the Spaghetti Nebula. A supernova remnant cataloged as Simeis 147 and Sh2-240, the glowing gas filaments cover nearly 3 degrees -- 6 full moons -- on the sky. That's about 150 light-years at the stellar debris cloud's estimated distance of 3,000 light-years. This sharp composite includes image data taken through a narrow-band filter to highlight emission from hydrogen atoms tracing the shocked, glowing gas. The supernova remnant has an estimated age of about 40,000 years, meaning light from the massive stellar explosion first reached Earth about 40,000 years ago. But the expanding remnant is not the only aftermath. The cosmic catastrophe also left behind a spinning neutron star or pulsar, all that remains of the original star's core.

NGC 6872: A Stretched Spiral Galaxy

NGC 6872: A Stretched Spiral Galaxy:

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2016 April 26



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NGC 6872: A Stretched Spiral Galaxy

Image Credit: FORS Team, 8.2-meter VLT Antu, ESO; Processing & License: Judy Schmidt


Explanation: What makes this spiral galaxy so long? Measuring over 700,000 light years across from top to bottom, NGC 6872, also known as the Condor galaxy, is one of the most elongated barred spiral galaxies known. The galaxy's protracted shape likely results from its continuing collision with the smaller galaxy IC 4970, visible just above center. Of particular interest is NGC 6872's spiral arm on the upper left, as pictured here, which exhibits an unusually high amount of blue star forming regions. The light we see today left these colliding giants before the days of the dinosaurs, about 300 million years ago. NGC 6872 is visible with a small telescope toward the constellation of the Peacock (Pavo).

Tomorrow's picture: ancient star ball



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Sunday, April 24, 2016

Milky Way in Moonlight

Milky Way in Moonlight:

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2016 April 23


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Milky Way in Moonlight

Image Credit & Copyright: Babak Tafreshi (TWAN)


Explanation: A waning crescent moon, early morning twilight, and Al Hamra's city lights on the horizon can't hide the central Milky Way in this skyscape from planet Earth. Captured in a single exposure, the dreamlike scene looks southward across the region's grand canyon from Jabal Shams (Sun Mountain), near the highest peak in Oman, on the Arabian Peninsula. Mist, moonlight, and shadows still play along the steep canyon walls. Dark rifts along the luminous band of the Milky Way are the galaxy's cosmic dust clouds. Typically hundreds of light-years distant, they obscure starlight along the galactic plane, viewed edge-on from the Solar System's perspective.

Tomorrow's picture: star stuff



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Saturday, April 23, 2016

Asperatus Clouds Over New Zealand

Asperatus Clouds Over New Zealand:

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2016 April 17


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Asperatus Clouds Over New Zealand

Image Credit & Copyright: Witta Priester


Explanation: What kind of clouds are these? Although their cause is presently unknown, such unusual atmospheric structures, as menacing as they might seem, do not appear to be harbingers of meteorological doom. Known informally as Undulatus asperatus clouds, they can be stunning in appearance, unusual in occurrence, are relatively unstudied, and have even been suggested as a new type of cloud. Whereas most low cloud decks are flat bottomed, asperatus clouds appear to have significant vertical structure underneath. Speculation therefore holds that asperatus clouds might be related to lenticular clouds that form near mountains, or mammatus clouds associated with thunderstorms, or perhaps a foehn wind -- a type of dry downward wind that flows off mountains. Such a wind called the Canterbury arch streams toward the east coast of New Zealand's South Island. The featured image, taken above Hanmer Springs in Canterbury, New Zealand, in 2005, shows great detail partly because sunlight illuminates the undulating clouds from the side.

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Tomorrow's picture: space station



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Andromeda Rising over Colombia

Andromeda Rising over Colombia:

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2016 April 19


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Explanation: What’s that rising over the hill? A galaxy. Never having seen a galaxy themselves, three friends of an industrious astrophotographer experienced an exhilarating night sky firsthand that featured not only the band of our Milky Way galaxy but also Milky Way's neighbor -- the Andromeda galaxy. Capturing the scene required careful pre-shot planning including finding a good site, waiting for good weather, balancing relative angular sizes with a zoom lens, managing ground lighting, and minimizing atmospheric light absorption. The calculated shot therefore placed the friends on a hill about 250 meters away and about 50 meters up. The featured single-exposure image was taken last July 26 at about 11:30 pm in Guatape, Colombia, about two hours from Medellin. The surrounding stars visible are all nearby in our own galaxy, while the small galaxy just above M31 is Andromeda's satellite M110.

Galaxy Einstein Ring

Galaxy Einstein Ring:

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2016 April 20


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Galaxy Einstein Ring

Image Credit: Y. Hezaveh (Stanford) et al., ALMA (NRAO/ESO/NAOJ), NASA/ESA Hubble Space Telescope


Explanation: Can one galaxy hide behind another? Not in the case of SDP.81. Here the foreground galaxy, shown in blue in an image taken by the Hubble Space Telescope, acts like a huge gravitational lens, pulling light from a background galaxy, shown in red in an image taken in radio waves by the Atacama Large Millimeter Array (ALMA), around it, keeping it visible. The alignment is so precise that the distant galaxy is distorted into part of a ring around the foreground galaxy, a formation known as an Einstein ring. Detailed analysis of the gravitational lens distortions indicate that a small dark satellite galaxy participates in the deflections, bolstering indication that many satellite galaxies are quite dim and dominated by dark matter. That small galaxy is depicted by a small white dot on the left. Although spanning only a few arcseconds, the featured Einstein ring is really tens of thousands of light years across.

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Tomorrow's picture: Messier moment



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The Comet, the Owl, and the Galaxy

The Comet, the Owl, and the Galaxy:

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2016 April 21


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Explanation: Comet C/2014 S2 (PanSTARRS) poses for a Messier moment in this telescopic snapshot from April 18. In fact it shares the 1.5 degree wide field-of-view with two well-known entries in the 18th century comet-hunting astronomer's famous catalog. Outward bound and sweeping through northern skies just below the Big Dipper, the fading visitor to the inner Solar System was about 18 light-minutes from our fair planet. Dusty, edge-on spiral galaxy Messier 108 (upper right) is more like 45 million light-years away. A planetary nebula with an aging but intensely hot central star, the owlish Messier 97 is only about 12 thousand light-years distant though, still well within our own Milky Way galaxy. Astronomers expect the orbit of this comet PanSTARRS to return it to the inner Solar System around the year 4226.

NGC 7635: The Bubble Nebula

NGC 7635: The Bubble Nebula:

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2016 April 22



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NGC 7635: The Bubble Nebula

Image Credit: NASA, ESA, Hubble Heritage Team (STScI / AURA)

Explanation: Blown by the wind from a massive star, this interstellar apparition has a surprisingly familiar shape. Cataloged as NGC 7635, it is also known simply as The Bubble Nebula. Although it looks delicate, the 7 light-year diameter bubble offers evidence of violent processes at work. Above and left of the Bubble's center is a hot, O-type star, several hundred thousand times more luminous and around 45 times more massive than the Sun. A fierce stellar wind and intense radiation from that star has blasted out the structure of glowing gas against denser material in a surrounding molecular cloud. The intriguing Bubble Nebula and associated cloud complex lie a mere 7,100 light-years away toward the boastful constellation Cassiopeia. This sharp, tantalizing view of the cosmic bubble is a composite of Hubble Space Telescope image data from 2016, released to celebrate the 26th anniversary of Hubble's launch.

Celebrate: Planet Earth Day

Tomorrow's picture: Arabian nights



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Sunday, April 17, 2016

Cassini Approaches Saturn

Cassini Approaches Saturn:

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2016 April 10


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Cassini Approaches Saturn

Image Credit: Cassini Imaging Team, SWRI, JPL, ESA, NASA


Explanation: Cassini, a robot spacecraft launched in 1997 by NASA, became close enough in 2002 to resolve many rings and moons of its destination planet: Saturn. At that time, Cassini snapped several images during an engineering test. Several of those images were combined into the contrast-enhanced color composite featured here. Saturn's rings and cloud-tops are visible toward the image bottom, while Titan, its largest moon, is visible as the speck toward the top. When arriving at Saturn in July 2004, the Cassini orbiter began to circle and study the Saturnian system. A highlight was when Cassini launched the Huygens probe that made an unprecedented landing on Titan in 2005, sending back detailed pictures. Now nearing the end of its mission, Cassini is scheduled to embark on a Grand Finale phase in late 2016 where it will repeatedly dive between the giant planet and its innermost rings.

Tomorrow's picture: comet & cluster



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The Comet and the Star Cluster

The Comet and the Star Cluster:

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2016 April 11


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Explanation: Comet Linear has become unexpectedly bright. The comet, discovered in 2000, underwent a 100-fold outburst just a week before it passed a mere 14 lunar distances from Earth late last month. The comet was captured here last week at about magnitude 6 -- just bright enough to be seen by the unaided eye -- passing in front of the distant globular star cluster M14. Comet 252/P LINEAR is one of a rare group of comets that vacillate between the Earth and Jupiter every 5 years. How the comet will evolve from here is unknown, but hopes run high that it will remain a good object for binoculars in northern skies for the next week or two.

Combined Solar Eclipse Corona from Earth and Space

Combined Solar Eclipse Corona from Earth and Space:

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2016 April 12


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Combined Solar Eclipse Corona from Earth and Space

Image Credits: J. Vilinga (Angola, IAP), LASCO, NRL, SOHO, ESA, NASA;

Processing: R. Wittich; Composition & Copyright: S. Koutchmy (IAP, CNRS)


Explanation: Sometimes, a total eclipse is a good time to eye the Sun. Taking advantage of an unusual juxtaposition of Earth, Moon and Sun, the featured image depicts the total solar eclipse that occurred last month as it appeared -- nearly simultaneously -- from both Earth and space. The innermost image shows the total eclipse from the ground, with the central pupil created by the bright Sun covered by a comparatively dark Moon. Surrounding the blocked solar disk is the tenuous corona of Sun imaged in white light, easily visible from the ground only during an eclipse. Normally, this corona is hard to track far from the Sun, but the featured montage matches it to false-colored observations of the Sun from NASA and ESA's space-based, Sun-orbiting, Solar and Heliospheric Observatory (SOHO). Observations like this allow the study of the constantly changing magnetic activity both near and far from the Sun, the same activity that ultimately drives Earth's auroras.

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Tomorrow's picture: orion in red and blue



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Orion in Red and Blue

Orion in Red and Blue:

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2016 April 13


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Explanation: When did Orion become so flashy? This colorful rendition of part of the constellation of Orion comes from red light emitted by hydrogen and sulfur (SII), and blue-green light emitted by oxygen (OIII). Hues on the featured image were then digitally reassigned to be indicative of their elemental origins -- but also striking to the human eye. The breathtaking composite was painstakingly composed from hundreds of images which took nearly 200 hours to collect. Pictured, Barnard's Loop, across the image bottom, appears to cradle interstellar constructs including the intricate Orion Nebula seen just right of center. The Flame Nebula can also be quickly located, but it takes a careful eye to identify the slight indentation of the dark Horsehead Nebula. As to Orion's flashiness -- a leading explanation for the origin of Barnard's Loop is a supernova blast that occurred about two million years ago.

Mercury and Crescent Moon Set

Mercury and Crescent Moon Set:

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2016 April 15


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Mercury and Crescent Moon Set

Image Credit & Copyright: Miguel Claro (TWAN, Dark Sky Alqueva)

Explanation: Innermost planet Mercury and a thin crescent Moon are never found far from the Sun in planet Earth's skies. Taken near dusk on April 8, this colorful evening skyscape shows them both setting toward the western horizon just after the Sun. The broad Tagus River and city lights of Lisbon, Portugal run through the foreground under the serene twilight sky. Near perigee or closest approach to Earth, the Moon's bright, slender crescent represents about 3 percent of the lunar disk in sunlight. Of course as seen from the Moon, a nearly full Earth would light up the lunar night, and that strong perigee earthshine makes the rest of the lunar disk visible in this scene. Bright Mercury stays well above the western horizon at sunset for northern skywatchers in the coming days. The fleeting planet reaches maximum elongation, or angular distance from the Sun, on April 18. But Mercury will swing back toward the Sun and actually cross the solar disk on May 9, the first transit of Mercury since November 8, 2006.

Tomorrow's picture: Heliopause Electrostatic Rapid Transit System



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Heliopause Electrostatic Rapid Transit System

Heliopause Electrostatic Rapid Transit System:

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2016 April 16



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Heliopause Electrostatic Rapid Transit System

Illustration Credit: NASA, Marshall Space Flight Center

Explanation: Want to take a fast trip to the edge of the Solar System? Consider a ride on a Heliopause Electrostatic Rapid Transit System (HERTS). The concept is currently being tested and it might take only 10 to 15 years to make the trip of over 100 Astronomical Units (15 billion kilometers). That's fast compared to the 35 years it took Voyager 1, presently humanity's most distant spacecraft, to approach the heliopause or outer boundary of the influence of the solar wind. HERTS would use an advanced electric solar sail that works by extending multiple, 20 kilometer or so long, 1 millimeter thin, positively charged wires from a rotating spacecraft. The electrostatic force generated repels fast moving solar wind protons to create thrust. Compared to a reflective solar light sail, another propellantless deep space propulsion system, the electric solar wind sail could continue to accelerate at greater distances from the Sun, still developing thrust as it cruised toward the outer planets.

Tomorrow's picture: undulatus asperatus



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Saturday, April 9, 2016

The Rotation Of The Earth

The Rotation Of The Earth:



Earth seen by MESSENGER


What if someone were to tell you that at any given moment, you were traveling at speeds well in excess of the speed of sound? You might think they were crazy, given that - as best as you could tell - you were standing on solid ground, and not in the cockpit of a supersonic jet. Nevertheless, the statement is correct. At any given moment, we are all moving at a speed of about 1,674 kilometers an hour, thanks to the Earth's rotation,By definition, the Earth's rotation is the amount of time that it takes to rotate once on its axis. This is, apparently, accomplished once a day - i.e. every 24 hours. However, there are actually two different kinds of rotation that need to be considered here. For one, there's the amount of time it take for the Earth to turn once on its axis so that it returns to the same orientation compared to the rest of the Universe. Then there's how long it takes for the Earth to turn so that the Sun returns to the same spot in the sky.

Solar vs. Sidereal Day:

As we all know, it takes exactly 24 hours for the Sun to return to the same spot in the sky, which would seem obvious. 24 hours is what we think of as being a complete day, and the time it takes to transition from day to night and back again. But in truth, it actually takes the Earth 23 hours, 56 minutes, and 4.09 seconds to turn rotate once on its axis compared to the background stars.Why the difference? Well, that would be because the Earth is orbiting around the Sun, completing one orbit in just over 365 days. If you divide 24 hours by 365 days, you'll see that you're left with about 4 minutes per day. In other words, the Earth rotates on its axis, but it's also orbiting around the Sun, so the Sun's position in the sky catches up by 4 minutes each day.The amount of time it takes for the Earth to rotate once on its axis is known as a sidereal day - which is 23.9344696 hours. Because this type of day-measurement is based on the Earth's position relative to the stars, astronomers use it as a time-keeping system to keep track of where stars will appear in the night sky, mainly so they will know which direction to point their telescopes in.

The amount of time it takes for the Sun to return to the same spot in the sky is called a solar day, which is 24 hours. However, this varies through the year, and the accumulated effect produces seasonal deviations of up to 16 minutes from the average. This is caused by two factors, which include the Earth's elliptical orbit around the Sun and it's axial tilt.

Orbit and Axial Tilt:

As Johannes Kepler stated in his Astronomia Nova (1609), the Earth and Solar planets do not rotate about the Sun in perfect circles. This is known as Kepler's First Law, which states that "the orbit of a planet about the Sun is an ellipse with the Sun’s center of mass at one focus". At perihelion (i.e. its closest) it is 147,095,000 km (91,401,000 mi) from the Sun; whereas at aphelion, it is 152,100,000 km (94,500,000 mi).This change in distance means that the Earth's orbital speed increases when it is closest to the Sun. While its speed averages out to about 29.8 km/s (18.5 mps) or 107,000 km/h (66487 mph), it actually ranges by a full km per second during the course of the year - between 30.29 km/s and 29.29 km/s (109,044 - 105,444 km/h; 67,756.8 - 65,519.864 mph).Earth's axis is also inclined at approximately 23.439° towards the ecliptic. This means that when the Sun crosses the equator at both equinoxes, it's daily shift relative to the background stars is at an angle to the equator. In June and December, when the Sun is farthest from the celestial equator, a given shift along the ecliptic corresponds to a large shift at the equator.So apparent solar days are shorter in March and September than in June or December. In northern temperate latitudes, the Sun rises north of true east during the summer solstice, and sets north of true west, reversing in the winter. The Sun rises south of true east in the summer for the southern temperate zone, and sets south of true west.

Rotational Velocity:

As stated earlier, the Earth's is spinning rather rapidly. In fact, scientists have determined that Earth's rotational velocity at the equator is 1,674.4 km/h. This means that just by standing on the equator, a person would already be traveling at a speed in excess of the speed of sound in a circle. But much like measuring a day, the Earth's rotation can be measured in one of two different ways.Earth's rotation period relative to the fixed stars is known as a "stellar day", which is 86,164.098903691 seconds of mean solar time (or 23 hours, 56 minutes and 4.0989 seconds). Earth's rotation period relative to the precessing or moving mean vernal equinox, meanwhile, is 23 hours 56 minutes and 4.0905 seconds of mean solar time. Not a major difference, but a difference nonetheless.

However, the planet is slowing slightly with the passage of time, due to the tidal effects the Moon has on Earth's rotation. Atomic clocks show that a modern day is longer by about 1.7 milliseconds than a century ago, slowly increasing the rate at which UTC is adjusted by leap seconds. The Earth's rotation also goes from the west towards east, which is why the Sun rises in the east and sets in the west.=

Earth's Formation:

Another interesting thing about the Earth's rotation is how it all got started. Basically, the planet's rotation is due to the angular momentum of all the particles that came together to create our planet 4.6 billion years ago. Before that, the Earth, the Sun and the rest of the Solar System were part of a giant molecular cloud of hydrogen, helium, and other heavier elements.As the cloud collapsed down, the momentum of all the particles set the cloud spinning. The current rotation period of the Earth is the result of this initial rotation and other factors, including tidal friction and the hypothetical impact of Theia - a collision with a Mars-sized object that is thought to have taken place approx. 4.5 billion years ago and formed the Moon.This rapid rotation is also what gives the Earth it's shape, flattening it out into an oblate spheroid (or what looks like a squished ball). This special shape of our planet means that points along the equator are actually further from the center of the Earth than at the poles.In short, the world has been spinning since its inception. And, contrary to what some might say, it actually is slowing down, albeit at an incredibly slow rate. But of course, by the time it slows significantly, we will have likely ceased to exist, or slipped its "surly bonds" and become an interplanetary species.We've written several articles about Earth here Universe Today. Here's an article about how fast the Earth rotates, and here's an article about why the Earth rotates.If you'd like more information on the Earth's rotation, check out NASA's Solar System Exploration Guide on Earth. And here's a link to NASA's Earth Observatory.We've also recorded an episode of Astronomy Cast all about Earth. Listen here, Episode 51: Earth.

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