Pillar at Sunset

Reddened light from the setting Sun illuminates the cloud banks hugging this snowy, rugged terrain. Inspiring a moment of quiet contemplation, the sunset scene included a remarkable pillar of light that seemed to connect the clouds in the sky with the mountains below. Known as a Sun pillar, the luminous column was produced by sunlight reflecting from flat, six-sided ice crystals formed high in the cold atmosphere and fluttering toward the ground. In March 2010, astronomers watched this Sun pillar slowly fade, as the twilight deepened and clearing, dark skies came to Mt. Jelm and the Wyoming Infrared Observatory.

Image Credit & Copyright: David Alquist

Explanation from: http://apod.nasa.gov/apod/ap100306.html

PLEASE SHARE

Tweet

Read More

Space Shuttle Discovery's Last Flight

Climbing into cloudy skies, the Space Shuttle Orbiter Discovery (OV-103) took off from Kennedy Space Center Tuesday at 7 am local time on 17 April 2012. This time, its final departure from KSC, it rode atop a modified Boeing 747 Shuttle Carrier Aircraft. Following a farewell flyover of the Space Coast, Goddard Space Flight Center, and Washington DC, Discovery headed for Dulles International Airport in Virginia, destined to reside at the Smithsonian's National Air and Space Museum Udvar-Hazy Center. Discovery retires as NASA's most traveled shuttle orbiter, covering more than 148 million miles in 39 missions that included the delivery of the Hubble Space Telescope to orbit. Operational from 1984 through 2011, Discovery spent a total of one year in space.

Image Credit & Copyright: Ben Cooper
Explanation from: http://apod.nasa.gov/apod/ap120419.html

PLEASE SHARE

Tweet

Read More

First Shuttle Launch

    

A new era in space flight began on April 12, 1981, when Space Shuttle Columbia, or STS-1, soared into orbit from NASA's Kennedy Space Center in Florida. 

Astronaut John Young, a veteran of four previous spaceflights including a walk on the moon in 1972, commanded the mission. Navy test pilot Bob Crippen piloted the mission and would go on to command three future shuttle missions. The shuttle was humankind's first re-usable spacecraft. The orbiter would launch like a rocket and land like a plane. The two solid rocket boosters that helped push them into space would also be re-used, after being recovered in the ocean. Only the massive external fuel tank would burn up as it fell back to Earth. It was all known as the Space Transportation System.

Twenty years prior to the historic launch, on April 12, 1961, the era of human spaceflight began when Russian Cosmonaut Yuri Gagarin became the first human to orbit the Earth in his Vostock I spacecraft. The flight lasted 108 minutes. 

Pictured here: a timed exposure of STS-1, at Launch Pad A, Complex 39, turns the space vehicle and support facilities into a night- time fantasy of light. Structures to the left of the shuttle are the fixed and the rotating service structure. 

Image Credit: NASA

Explanation from: http://www.nasa.gov/multimedia/imagegallery/image_feature_2488.html

PLEASE SHARE

Tweet

Read More

Spring Fling: Sun Emits a Mid-Level Flare

The M6.5 flare on the morning of April 11, 2013, was also associated with an Earth-directed coronal mass ejection (CME), another solar phenomenon that can send billions of tons of solar particles into space and can reach Earth one to three days later. CMEs can affect electronic systems in satellites and on the ground. Experimental NASA research models show that the CME began at 3:36 a.m. EDT on April 11, leaving the sun at over 600 miles per second.

Earth-directed CMEs can cause a space weather phenomenon called a geomagnetic storm, which occurs when they connect with the outside of the Earth's magnetic envelope, the magnetosphere, for an extended period of time.

The recent space weather also resulted in a weak solar energetic particle (SEP) event near Earth. These events occur when very fast protons and charged particles from the sun travel toward Earth, sometimes in the wake of a solar flare. These events are also referred to as solar radiation storms. Any harmful radiation from the event is blocked by the magnetosphere and atmosphere, so cannot reach humans on Earth. Solar radiation storms can, however, disturb the regions through which high frequency radio communications travel.

NOAA's Space Weather Prediction Center is the United States Government official source for space weather forecasts, alerts, watches and warnings. NASA and NOAA – as well as the US Air Force Weather Agency (AFWA) and others -- keep a constant watch on the sun to monitor for space weather effects such as geomagnetic storms. With advance notification many satellites, spacecraft and technologies can be protected from the worst effects.

The sun emitted a mid-level flare, peaking at 3:16 a.m. EDT on April 11, 2013.

Solar flares are powerful bursts of radiation. Harmful radiation from a flare cannot pass through Earth's atmosphere to physically affect humans on the ground, however -- when intense enough -- they can disturb the atmosphere in the layer where GPS and communications signals travel. This disrupts the radio signals for as long as the flare is ongoing, anywhere from minutes to hours.

This flare is classified as an M6.5 flare, some ten times less powerful than the strongest flares, which are labeled X-class flares. M-class flares are the weakest flares that can still cause some space weather effects near Earth. This flare produced a radio blackout that has since subsided. The blackout was categorized as an R2 on a scale between R1 and R5 on NOAA’s space weather scales.

This is the strongest flare seen so far in 2013. Increased numbers of flares are quite common at the moment, since the sun's normal 11-year activity cycle is ramping up toward solar maximum, which is expected in late 2013. Humans have tracked this solar cycle continuously since it was discovered, and it is normal for there to be many flares a day during the sun's peak activity.

Images Credit: ESA&NASA/SOHO/GSFC
Explanation from: http://www.nasa.gov/mission_pages/sunearth/news/News031513-m6flare.html

PLEASE SHARE

Tweet

Read More

Starburst Galaxy M82

This mosaic image is the sharpest wide-angle view ever obtained of M82. The galaxy is remarkable for its bright blue disk, webs of shredded clouds, and fiery-looking plumes of glowing hydrogen blasting out of its central regions.

Throughout the galaxy's center, young stars are being born 10 times faster than they are inside our entire Milky Way Galaxy. The resulting huge concentration of young stars carved into the gas and dust at the galaxy's center. The fierce galactic superwind generated from these stars compresses enough gas to make millions of more stars.

In M82, young stars are crammed into tiny but massive star clusters. These, in turn, congregate by the dozens to make the bright patches, or "starburst clumps," in the central parts of M82. The clusters in the clumps can only be distinguished in the sharp Hubble images. Most of the pale, white objects sprinkled around the body of M82 that look like fuzzy stars are actually individual star clusters about 20 light-years across and contain up to a million stars.

The rapid rate of star formation in this galaxy eventually will be self-limiting. When star formation becomes too vigorous, it will consume or destroy the material needed to make more stars. The starburst then will subside, probably in a few tens of millions of years.

Located 12 million light-years away, M82 appears high in the northern spring sky in the direction of the constellation Ursa Major, the Great Bear. It is also called the "Cigar Galaxy" because of the elliptical shape produced by the oblique tilt of its starry disk relative to our line of sight.

The observation was made in March 2006, with the Advanced Camera for Surveys' Wide Field Channel. Astronomers assembled this six-image composite mosaic by combining exposures taken with four colored filters that capture starlight from visible and infrared wavelengths as well as the light from the glowing hydrogen filaments.

Image Credit: NASA, ESA, and The Hubble Heritage Team (STScI/AURA)
Explanation from: http://hubblesite.org/newscenter/archive/releases/2006/14/image/a/

PLEASE SHARE

Tweet

Read More

A Sun Pillar over Sweden

Have you ever seen a sun pillar? When the air is cold and the Sun is rising or setting, falling ice crystals can reflect sunlight and create an unusual column of light. Ice sometimes forms flat, six-sided shaped crystals as it falls from high-level clouds. Air resistance causes these crystals to lie nearly flat much of the time as they flutter to the ground. Sunlight reflects off crystals that are properly aligned, creating the sun-pillar effect. In this picture taken in December 2012, a sun-pillar reflects light from a Sun setting over Östersund, Sweden.

Image Credit & Copyright: Göran Strand

Explanation from: http://apod.nasa.gov/apod/ap121218.html

PLEASE SHARE

Tweet

Read More

Out of This Whirl: the Whirlpool Galaxy (M51) and Companion Galaxy

The graceful, winding arms of the majestic spiral galaxy M51 (NGC 5194) appear like a grand spiral staircase sweeping through space. They are actually long lanes of stars and gas laced with dust.

This sharpest-ever image of the Whirlpool Galaxy, taken in January 2005 with the Advanced Camera for Surveys aboard NASA's Hubble Space Telescope, illustrates a spiral galaxy's grand design, from its curving spiral arms, where young stars reside, to its yellowish central core, a home of older stars. The galaxy is nicknamed the Whirlpool because of its swirling structure.

The Whirlpool's most striking feature is its two curving arms, a hallmark of so-called grand-design spiral galaxies. Many spiral galaxies possess numerous, loosely shaped arms which make their spiral structure less pronounced. These arms serve an important purpose in spiral galaxies. They are star-formation factories, compressing hydrogen gas and creating clusters of new stars. In the Whirlpool, the assembly line begins with the dark clouds of gas on the inner edge, then moves to bright pink star-forming regions, and ends with the brilliant blue star clusters along the outer edge.

Some astronomers believe that the Whirlpool's arms are so prominent because of the effects of a close encounter with NGC 5195, the small, yellowish galaxy at the outermost tip of one of the Whirlpool's arms. At first glance, the compact galaxy appears to be tugging on the arm. Hubble's clear view, however, shows that NGC 5195 is passing behind the Whirlpool. The small galaxy has been gliding past the Whirlpool for hundreds of millions of years.

As NGC 5195 drifts by, its gravitational muscle pumps up waves within the Whirlpool's pancake-shaped disk. The waves are like ripples in a pond generated when a rock is thrown in the water. When the waves pass through orbiting gas clouds within the disk, they squeeze the gaseous material along each arm's inner edge. The dark dusty material looks like gathering storm clouds. These dense clouds collapse, creating a wake of star birth, as seen in the bright pink star-forming regions. The largest stars eventually sweep away the dusty cocoons with a torrent of radiation, hurricane-like stellar winds, and shock waves from supernova blasts. Bright blue star clusters emerge from the mayhem, illuminating the Whirlpool's arms like city streetlights.

The Whirlpool is one of astronomy's galactic darlings. Located 31 million light-years away in the constellation Canes Venatici (the Hunting Dogs), the Whirlpool's beautiful face-on view and closeness to Earth allow astronomers to study a classic spiral galaxy's structure and star-forming processes.

Image Credit: NASA, ESA, S. Beckwith (STScI), and The Hubble Heritage Team (STScI/AURA)

Explanation from: http://hubblesite.org/newscenter/archive/releases/2005/12/image/a/

PLEASE SHARE

Tweet

Read More

Stars in NGC 602a

The Small Magellanic Cloud (SMC) is one of the Milky Way's closest galactic neighbors. Even though it is a small, or so-called dwarf galaxy, the SMC is so bright that it is visible to the unaided eye from the Southern Hemisphere and near the equator. Many navigators, including Ferdinand Magellan who lends his name to the SMC, used it to help find their way across the oceans. 

Modern astronomers are also interested in studying the SMC (and its cousin, the Large Magellanic Cloud), but for very different reasons. Because the SMC is so close and bright, it offers an opportunity to study phenomena that are difficult to examine in more distant galaxies. 

New Chandra data of the SMC have provided one such discovery: the first detection of X-ray emission from young stars with masses similar to our Sun outside our Milky Way galaxy. The new Chandra observations of these low-mass stars were made of the region known as the "Wing" of the SMC. In this composite image of the Wing the Chandra data is shown in purple, optical data from the Hubble Space Telescope is shown in red, green and blue and infrared data from the Spitzer Space Telescope is shown in red. 

Astronomers call all elements heavier than hydrogen and helium -- that is, with more than two protons in the atom's nucleus -- "metals." The Wing is a region known to have fewer metals compared to most areas within the Milky Way. There are also relatively lower amounts of gas, dust, and stars in the Wing compared to the Milky Way. 

Taken together, these properties make the Wing an excellent location to study the life cycle of stars and the gas lying in between them. Not only are these conditions typical for dwarf irregular galaxies like the SMC, they also mimic ones that would have existed in the early Universe. 

Most star formation near the tip of the Wing is occurring in a small region known as NGC 602, which contains a collection of at least three star clusters. One of them, NGC 602a, is similar in age, mass, and size to the famous Orion Nebula Cluster. Researchers have studied NGC 602a to see if young stars -- that is, those only a few million years old -- have different properties when they have low levels of metals, like the ones found in NGC 602a. 

Using Chandra, astronomers discovered extended X-ray emission, from the two most densely populated regions in NGC 602a. The extended X-ray cloud likely comes from the population of young, low-mass stars in the cluster, which have previously been picked out by infrared and optical surveys, using Spitzer and Hubble respectively. This emission is not likely to be hot gas blown away by massive stars, because the low metal content of stars in NGC 602a implies that these stars should have weak winds. The failure to detect X-ray emission from the most massive star in NGC 602a supports this conclusion, because X-ray emission is an indicator of the strength of winds from massive stars. No individual low-mass stars are detected, but the overlapping emission from several thousand stars is bright enough to be observed. 

The Chandra results imply that the young, metal-poor stars in NGC 602a produce X-rays in a manner similar to stars with much higher metal content found in the Orion cluster in our galaxy. The authors speculate that if the X-ray properties of young stars are similar in different environments, then other related properties -- including the formation and evolution of disks where planets form -- are also likely to be similar. 

X-ray emission traces the magnetic activity of young stars and is related to how efficiently their magnetic dynamo operates. Magnetic dynamos generate magnetic fields in stars through a process involving the star's speed of rotation, and convection, the rising and falling of hot gas in the star's interior. 

The combined X-ray, optical and infrared data also revealed, for the first time outside our Galaxy, objects representative of an even younger stage of evolution of a star. These so-called "young stellar objects" have ages of a few thousand years and are still embedded in the pillar of dust and gas from which stars form, as in the famous "Pillars of Creation" of the Eagle Nebula. 

Image Credit: X-ray: NASA/CXC/Univ.Potsdam/L.Oskinova et al; Optical: NASA/STScI; Infrared: NASA/JPL-Caltech

Explanation from: http://www.nasa.gov/mission_pages/chandra/multimedia/ngc602a.html

PLEASE SHARE

Tweet

Read More

Alaskan Mountains Seen During IceBridge Transit

Alaskan mountains seen from high altitude aboard the NASA P-3B during the IceBridge transit flight from Thule to Fairbanks on March 21, 2013.

NASA's Operation IceBridge is an airborne science mission to study Earth's polar ice.

Image Credit: NASA/Goddard/Christy Hansen

PLEASE SHARE

Tweet

Read More

Herschel Sees Through Ghostly Pillars

This Herschel image of the Eagle nebula shows the self-emission of the intensely cold nebula’s gas and dust as never seen before. Each color shows a different temperature of dust, from around 10 degrees above absolute zero (10 Kelvin or minus 442 degrees Fahrenheit) for the red, up to around 40 Kelvin, or minus 388 degrees Fahrenheit, for the blue. 

Herschel reveals the nebula's intricate tendril nature, with vast cavities forming an almost cave-like surrounding to the famous pillars, which appear almost ghostly in this view. The gas and dust provide the material for the star formation that is still under way inside this enigmatic nebula. 

Far-infrared light has been color-coded to 70 microns for blue and 160 microns for green using the Photodetector Array Camera, and 250 microns for red using the Spectral and Photometric Imaging Receiver. 

Herschel is a European Space Agency cornerstone mission, with science instruments provided by consortia of European institutes and with important participation by NASA. NASA's Herschel Project Office is based at NASA's Jet Propulsion Laboratory, Pasadena, Calif. JPL contributed mission-enabling technology for two of Herschel's three science instruments. The NASA Herschel Science Center, part of the Infrared Processing and Analysis Center at the California Institute of Technology in Pasadena, supports the United States astronomical community. Caltech manages JPL for NASA. 

Image Credit: ESA/Herschel/PACS/SPIRE/Hill, Motte, HOBYS Key Programme Consortium

Explanation from: http://www.nasa.gov/mission_pages/herschel/multimedia/pia15260.html

PLEASE SHARE

Tweet

Read More

The Brightness of the Sun

The bright Sun, a portion of the International Space Station and Earth's horizon are featured in this image photographed during the STS-134 mission's fourth spacewalk in May 2011. The image was taken using a fish-eye lens attached to an electronic still camera. 

Image Credit: NASA

PLEASE SHARE

Tweet

Read More

Churning Out Stars

W3 is an enormous stellar nursery about 6,200 light-years away in the Perseus Arm, one of the Milky Way galaxy’s main spiral arms, which hosts both low- and high-mass star formation. In this image from the Herschel space observatory, the low-mass forming stars are seen as tiny yellow dots embedded in cool red filaments, while the highest-mass stars - with greater than eight times the mass of our Sun - emit intense radiation, heating up the gas and dust around them and appearing here in blue. 

This three-color image of W3 combines Herschel bands at 70 microns (blue), 160 microns (green) and 250 microns (red). The image spans about 2 by 2 degrees. North is up and east is to the left. 

Image Credit: ESA/PACS & SPIRE consortia, A. Rivera-Ingraham & P.G. Martin, Univ. Toronto, HOBYS Key Programme (F. Motte)
Explanation from: http://www.nasa.gov/mission_pages/herschel/multimedia/pia16881.html

PLEASE SHARE

Tweet

Read More

Building a Lunar Base with 3D Printing

Building a base on the Moon could theoretically be made much simpler by using a 3D printer to construct it from local materials.

The concept was recently endorsed by the European Space Agency (ESA) which is now collaborating with architects to gauge the feasibility of 3D printing using lunar soil.

“Terrestrial 3D printing technology has produced entire structures,” explained Laurent Pambaguian, heading the project for ESA. “Our industrial team investigated if it could similarly be employed to build a lunar habitat.”

According to Pambaguian, ESA’s partners have devised a weight-bearing “catenary” dome design with a cellular structured wall to help shield against micrometeoroids and space radiation – incorporating a pressurized inflatable to shelter astronauts.

Meanwhile, a hollow closed-cell structure – somewhat reminiscent of bird bones – provides a combination of strength and weight. The base’s design was guided in turn by the properties of 3D-printed lunar soil, with a 1.5 ton building block produced as a demonstration.

“3D printing offers a potential means of facilitating lunar settlement with reduced logistics from Earth,” said Scott Hovland of ESA’s human spaceflight team. “The new possibilities this work opens up can then be considered by international space agencies as part of the current development of a common exploration strategy.”

Essentially, 3D “printouts” are built up layer by layer. A mobile printing array of nozzles on a 6 m frame sprays a binding solution onto a sand-like building material. First, the simulated lunar material is mixed with magnesium oxide to turn it into ‘paper’ to print with. Then for the structural ‘ink’ a binding salt is applied to convert the material to a stone-like solid.

Current 3D printers build at a rate of around 2 m per hour, while next-gen designs should attain 3.5 m per hour, completing an entire building in a week.

Images Credit: ESA/Foster + Partners
Explanation from: http://lunarscience.nasa.gov/articles/building-a-lunar-base-with-3d-printing/

PLEASE SHARE

Tweet

Read More

Mammatus Clouds over Saskatchewan

Normal cloud bottoms are flat. This is because moist warm air that rises and cools will condense into water droplets at a specific temperature, which usually corresponds to a very specific height. As water droplets grow, an opaque cloud forms. Under some conditions, however, cloud pockets can develop that contain large droplets of water or ice that fall into clear air as they evaporate. Such pockets may occur in turbulent air near a thunderstorm. Resulting mammatus clouds can appear especially dramatic if sunlit from the side. These mammatus clouds were photographed over Regina, Saskatchewan, Canada in 2011.

Image Credit: Craig Lindsay
Explanation from: http://apod.nasa.gov/apod/ap121023.html

PLEASE SHARE

Tweet

Read More

Earth - The Water Planet

Viewed from space, the most striking feature of our planet is the water. In both liquid and frozen form, it covers 75% of the Earth’s surface. It fills the sky with clouds. Water is practically everywhere on Earth, from inside the rocky crust to inside our cells.

This detailed, photo-like view of Earth is based largely on observations from the Moderate Resolution Imaging Spectroradiometer (MODIS) on NASA’s Terra satellite. It is one of many images of our watery world featured in a new story examining water in all of its forms and functions.

Here is an excerpt:

“In all, the Earth’s water content is about 1.39 billion cubic kilometers (331 million cubic miles), with the bulk of it, about 96.5%, being in the global oceans. As for the rest, approximately 1.7% is stored in the polar icecaps, glaciers, and permanent snow, and another 1.7% is stored in groundwater, lakes, rivers, streams, and soil.

Only a thousandth of 1% of the water on Earth exists as water vapor in the atmosphere. Despite its small amount, this water vapor has a huge influence on the planet. Water vapor is a powerful greenhouse gas, and it is a major driver of the Earth’s weather and climate as it travels around the globe, transporting heat with it.

For human needs, the amount of freshwater for drinking and agriculture is particularly important. Freshwater exists in lakes, rivers, groundwater, and frozen as snow and ice. Estimates of groundwater are particularly difficult to make, and they vary widely. Groundwater may constitute anywhere from approximately 22 to 30% of fresh water, with ice accounting for most of the remaining 78 to 70%."

Image Credit: Robert Simmon and Marit Jentoft-Nilsen/MODIS
Explanation from: http://earthobservatory.nasa.gov/IOTD/view.php?id=46209

PLEASE SHARE

Tweet

Read More

Star-Forming Region S106

The bipolar star-forming region, called Sharpless 2-106, looks like a soaring, celestial snow angel. The outstretched "wings" of the nebula record the contrasting imprint of heat and motion against the backdrop of a colder medium.

Sharpless 2-106, Sh2-106 or S106 for short, lies nearly 2,000 light-years from us. The nebula measures several light-years in length. It appears in a relatively isolated region of the Milky Way galaxy.

A massive, young star, IRS 4 (Infrared Source 4), is responsible for the furious activity we see in the nebula. Twin lobes of super-hot gas, glowing blue in this image, stretch outward from the central star. This hot gas creates the "wings" of our angel.

A ring of dust and gas orbiting the star acts like a belt, cinching the expanding nebula into an "hourglass" shape. Hubble's sharp resolution reveals ripples and ridges in the gas as it interacts with the cooler interstellar medium.

Dusky red veins surround the blue emission from the nebula. The faint light emanating from the central star reflects off of tiny dust particles. This illuminates the environment around the star, showing darker filaments of dust winding beneath the blue lobes.

Detailed studies of the nebula have also uncovered several hundred brown dwarfs. At purely infrared wavelengths, more than 600 of these sub-stellar objects appear. These "failed" stars weigh less than a tenth of our Sun. Because of their low mass, they cannot produce sustained energy through nuclear fusion like our Sun does. They encompass the nebula in a small cluster.

The Hubble images were taken in February 2011 with the Wide Field Camera 3. Visible narrow-band filters that isolate the hydrogen gas were combined with near-infrared filters that show structure in the cooler gas and dust.

Image Credit: NASA, ESA, and the Hubble Heritage Team (STScI/AURA)Explanation from: http://hubblesite.org/newscenter/archive/releases/2011/38/image/a/

PLEASE SHARE

Tweet

Read More

The M106 Galaxy

Working with astronomical image processors at the Space Telescope Science Institute in Baltimore, Md., renowned astrophotographer Robert Gendler has taken science data from the Hubble Space Telescope (HST) archive and combined it with his own ground-based observations to assemble a photo illustration of the magnificent spiral galaxy M106.

Gendler retrieved archival Hubble images of M106 to assemble a mosaic of the center of the galaxy. He then used his own and fellow astrophotographer Jay GaBany's observations of M106 to combine with the Hubble data in areas where there was less coverage, and finally, to fill in the holes and gaps where no Hubble data existed.

The center of the galaxy is composed almost entirely of HST data taken by the Advanced Camera for Surveys, Wide Field Camera 3, and Wide Field Planetary Camera 2 detectors. The outer spiral arms are predominantly HST data colorized with ground-based data taken by Gendler's and GaBany's 12.5-inch and 20-inch telescopes, located at very dark remote sites in New Mexico. The image also reveals the optical component of the "anomalous arms" of M106, seen here as red, glowing hydrogen emission.

Robert Gendler is a physician by profession but has been active in astrophotography for two decades. Robert started taking astro-images from his driveway in suburban Connecticut. He then spent several years imaging remotely from places like New Mexico and Western Australia. More recently, Robert has been spending his time assembling hybrid images from multiple data sources including the Hubble Legacy Archive. 

This portrait of M106 contains only the inner structure around the halo and nucleus of this Seyfert II active galaxy. Large amounts of gas from the galaxy are thought to be falling into and fueling a supermassive black hole contained in the nucleus. Also known as NGC 4258, M106 lies 23.5 million light-years away, in the constellation Canes Venatici.

Image Credit:NASA, ESA, the Hubble Heritage Team (STScI/AURA), and R. Gendler (for the Hubble Heritage Team)
Explanation from: http://hubblesite.org/newscenter/archive/releases/2013/06/image/a/

PLEASE SHARE

Tweet

Read More

A cloud of ash above Puyehue-Cordón Caulle Volcano

Osorno, Los Lagos, Chile

June 5, 2011

Image Credit & Copyright: Claudio Santana

PLEASE SHARE

Tweet

Read More

Comet C/2011 L4 - PANSTARRS

Still looking for that comet? Comet PanSTARRS (C/2011 L4) naked-eye appearance in the northern hemisphere is described by successful comet spotters as a dim star with faint a tail. If you want to catch it the next few days could be your best bet. Start looking low and almost due west about 45 minutes after sunset. Of course, clear skies and a pair of binoculars should help a lot. Sky photographer Jean-Luc Dauvergne found suitable weather and western horizon for this comet and crescent Moon portrait after a road trip on March 13. Seeing PanSTARRS for the first time, he recorded the beautiful twilight scene with a telephoto lens near historical Alesia in France.

Image Credit & Copyright: Jean-Luc Dauvergne
Explanation from: http://apod.nasa.gov/apod/ap130316.html

PLEASE SHARE

Tweet

Read More

Hubble Panoramic View of Orion Nebula Reveals Thousands of Stars

This dramatic image offers a peek inside a cavern of roiling dust and gas where thousands of stars are forming. The image, taken by the Advanced Camera for Surveys (ACS) aboard NASA's Hubble Space Telescope, represents the sharpest view ever taken of this region, called the Orion Nebula. More than 3,000 stars of various sizes appear in this image. Some of them have never been seen in visible light. These stars reside in a dramatic dust-and-gas landscape of plateaus, mountains, and valleys that are reminiscent of the Grand Canyon.

The Orion Nebula is a picture book of star formation, from the massive, young stars that are shaping the nebula to the pillars of dense gas that may be the homes of budding stars. The bright central region is the home of the four heftiest stars in the nebula. The stars are called the Trapezium because they are arranged in a trapezoid pattern. Ultraviolet light unleashed by these stars is carving a cavity in the nebula and disrupting the growth of hundreds of smaller stars. Located near the Trapezium stars are stars still young enough to have disks of material encircling them. These disks are called protoplanetary disks or "proplyds" and are too small to see clearly in this image. The disks are the building blocks of solar systems.

The bright glow at upper left is from M43, a small region being shaped by a massive, young star's ultraviolet light. Astronomers call the region a miniature Orion Nebula because only one star is sculpting the landscape. The Orion Nebula has four such stars. Next to M43 are dense, dark pillars of dust and gas that point toward the Trapezium. These pillars are resisting erosion from the Trapezium's intense ultraviolet light. The glowing region on the right reveals arcs and bubbles formed when stellar winds - streams of charged particles ejected from the Trapezium stars — collide with material.

The faint red stars near the bottom are the myriad brown dwarfs that Hubble spied for the first time in the nebula in visible light. Sometimes called "failed stars," brown dwarfs are cool objects that are too small to be ordinary stars because they cannot sustain nuclear fusion in their cores the way our Sun does. The dark red column, below, left, shows an illuminated edge of the cavity wall.

The Orion Nebula is 1,500 light-years away, the nearest star-forming region to Earth. Astronomers used 520 Hubble images, taken in five colors, to make this picture. They also added ground-based photos to fill out the nebula. The ACS mosaic covers approximately the apparent angular size of the full moon.

The Orion observations were taken between 2004 and 2005.

Image Credit: NASA,ESA, M. Robberto (Space Telescope Science Institute/ESA) and the Hubble Space Telescope Orion Treasury Project Team
Explanation from: http://hubblesite.org/newscenter/archive/releases/2006/01/image/a/

PLEASE SHARE

Tweet

Read More

A cloud of ash above Puyehue Volcano

Osorno, Los Lagos, Chile

June 5, 2011

Image Credit & Copyright: Claudio Santana

PLEASE SHARE

Tweet

Read More

Quiet Interlude in Solar Max

Something unexpected is happening on the Sun. 2013 was supposed to be the year of "solar maximum," the peak of the 11-year sunspot cycle. Yet 2013 has arrived and solar activity is relatively low. Sunspot numbers are well below their values from 2011, and strong solar flares have been infrequent.

The image above shows the Earth-facing surface of the Sun on February 28, 2013, as observed by the Helioseismic and Magnetic Imager (HMI) on NASA's Solar Dynamics Observatory. HMI observes the solar disk at 6173 Ångstroms, a wavelength designed to study surface oscillations and the magnetic field. HMI observed just a few small sunspots on an otherwise clean face, which is usually riddled with many spots during peak solar activity.

Image Credit: NASA/SDO
Explanation from: http://www.nasa.gov/multimedia/imagegallery/image_feature_2464.html

PLEASE SHARE

Tweet

Read More

Ancient Mars Could Have Supported Life

An analysis of a rock sample collected by NASA's Curiosity rover shows ancient Mars could have supported living microbes.

Scientists identified sulfur, nitrogen, hydrogen, oxygen, phosphorus and carbon -- some of the key chemical ingredients for life -- in the powder Curiosity drilled out of a sedimentary rock near an ancient stream bed in Gale Crater on the Red Planet last month.

"A fundamental question for this mission is whether Mars could have supported a habitable environment," said Michael Meyer, lead scientist for NASA's Mars Exploration Program at the agency's headquarters in Washington. "From what we know now, the answer is yes."

Clues to this habitable environment come from data returned by the rover's Sample Analysis at Mars (SAM) and Chemistry and Mineralogy (CheMin) instruments. The data indicate the Yellowknife Bay area the rover is exploring was the end of an ancient river system or an intermittently wet lake bed that could have provided chemical energy and other favorable conditions for microbes. The rock is made up of a fine-grained mudstone containing clay minerals, sulfate minerals and other chemicals. This ancient wet environment, unlike some others on Mars, was not harshly oxidizing, acidic or extremely salty.

The patch of bedrock where Curiosity drilled for its first sample lies in an ancient network of stream channels descending from the rim of Gale Crater. The bedrock also is fine-grained mudstone and shows evidence of multiple periods of wet conditions, including nodules and veins.

Curiosity's drill collected the sample at a site just a few hundred yards away from where the rover earlier found an ancient streambed in September 2012.

"Clay minerals make up at least 20 percent of the composition of this sample," said David Blake, principal investigator for the CheMin instrument at NASA's Ames Research Center in Moffett Field, Calif.

These clay minerals are a product of the reaction of relatively fresh water with igneous minerals, such as olivine, also present in the sediment. The reaction could have taken place within the sedimentary deposit, during transport of the sediment, or in the source region of the sediment. The presence of calcium sulfate along with the clay suggests the soil is neutral or mildly alkaline.

Scientists were surprised to find a mixture of oxidized, less-oxidized, and even non-oxidized chemicals, providing an energy gradient of the sort many microbes on Earth exploit to live. This partial oxidation was first hinted at when the drill cuttings were revealed to be gray rather than red.

"The range of chemical ingredients we have identified in the sample is impressive, and it suggests pairings such as sulfates and sulfides that indicate a possible chemical energy source for micro-organisms," said Paul Mahaffy, principal investigator of the SAM suite of instruments at NASA's Goddard Space Flight Center in Greenbelt, Md.

An additional drilled sample will be used to help confirm these results for several of the trace gases analyzed by the SAM instrument.

"We have characterized a very ancient, but strangely new 'gray Mars' where conditions once were favorable for life," said John Grotzinger, Mars Science Laboratory project scientist at the California Institute of Technology in Pasadena, Calif. "Curiosity is on a mission of discovery and exploration, and as a team we feel there are many more exciting discoveries ahead of us in the months and years to come."

Scientists plan to work with Curiosity in the "Yellowknife Bay" area for many more weeks before beginning a long drive to Gale Crater's central mound, Mount Sharp. Investigating the stack of layers exposed on Mount Sharp, where clay minerals and sulfate minerals have been identified from orbit, may add information about the duration and diversity of habitable conditions.

Image Credit: Daein Ballard
Explanation from: http://www.nasa.gov/mission_pages/msl/news/msl20130312.html

PLEASE SHARE

Tweet

Read More

NASA’s SDO Observes Earth, Lunar Transits in Same Day

On March 2, 2013, NASA’s Solar Dynamics Observatory (SDO) entered its semiannual eclipse season, a period of three weeks when Earth blocks its view of the Sun for a period of time each day. On March 11, however, SDO was treated to two transits. Earth blocked SDO’s view of the Sun from about 2:15 to 3:45 a.m. EDT. Later in the same day, from around 7:30 to 8:45 a.m. EDT, the Moon moved in front of the Sun for a partial eclipse.

When Earth blocks the Sun, the boundaries of Earth’s shadow appear fuzzy, since SDO can see some light from the Sun coming through Earth’s atmosphere. The line of Earth appears almost straight, since Earth - from SDO’s point of view - is so large compared to the Sun.

The eclipse caused by the Moon looks far different. Since the Moon has no atmosphere, its curved shape can be seen clearly, and the line of its shadow is crisp and clean. Any spacecraft observing the Sun from an orbit around Earth has to contend with such eclipses, but SDO's orbit is designed to minimize them as much as possible, with only two three-week eclipse seasons each year. The 2013 spring eclipse season continues until March 26. The fall season will begin on September 2.

Images Credit: NASA/SDO
Explanation from: http://www.nasa.gov/mission_pages/sdo/news/eclipse-spring2013.html

PLEASE SHARE

Tweet

Read More

Aurora over Kongsberg

Kongsberg, Norway

December 4, 2010

Image Credit & Copyright: Odd Smedsrud

PLEASE SHARE

Tweet

Read More

Sakurajima Volcano with Lightning

Why does a volcanic eruption sometimes create lightning? On this picture, the Sakurajima volcano in southern Japan was caught erupting in early January 2013. Magma bubbles so hot they glow shoot away as liquid rock bursts through the Earth's surface from below. This image is particularly notable, however, for the lightning bolts caught near the volcano's summit. Why lightning occurs even in common thunderstorms remains a topic of research, and the cause of volcanic lightning is even less clear. Surely, lightning bolts help quench areas of opposite but separated electric charges. One hypothesis holds that catapulting magma bubbles or volcanic ash are themselves electrically charged, and by their motion create these separated areas. Other volcanic lightning episodes may be facilitated by charge-inducing collisions in volcanic dust. Lightning is usually occurring somewhere on Earth, typically over 40 times each second.

Image Credit & Copyright: Martin Rietze
Explanation from: http://apod.nasa.gov/apod/ap130311.html

PLEASE SHARE

Tweet

Read More

Aurora over Langesund

Langesund, Norway

October 10, 2012

Image Credit & Copyright: Hugo Løhre

PLEASE SHARE

Tweet

Read More

Summer Lightning near Keota

The Pawnee National Grasslands in Colorado is an exceptional place both to observe nature and to stargaze. Observers have a nearly unobstructed view of the horizon. During the summer months, lightning can be seen miles away, and the night sky is generally free of annoying light pollution.

Image Credit: Robert Arn

PLEASE SHARE

Tweet

Read More

Tornado & Lightning

Lightning can serve as a natural sensing tool that allows scientists to understand what else could be happening in a storm

Image Credit: F. Smith

PLEASE SHARE

Tweet

Read More

The Milky Way Galaxy over Devils Tower

Was Devils Tower once an explosive volcano? Famous for its appearance in films such as Close Encounters, the origin of Devil's Tower in Wyoming, USA is still debated, with a leading hypothesis holding that it is a hardened lava plume that probably never reached the surface to become a volcano. The lighter rock that once surrounded the dense volcanic neck has now eroded away, leaving the dramatic tower. High above, the central band of the Milky Way Galaxy arches across the sky. Many notable sky objects are visible, including dark strands of the Pipe Nebula and the reddish Lagoon Nebula to the tower's right. Green grass and trees line the moonlit foreground, while clouds appear near the horizon to the tower's left. Unlike many other international landmarks, mountaineers are permitted to climb Devils Tower.

Image Credit & Copyright: Wally Pacholka
Explanation: http://apod.nasa.gov/apod/ap090729.html

PLEASE SHARE

Tweet

Read More

Eclipse over the Temple of Poseidon

What's happened to the Sun? The Moon moved to partly block the Sun for a few minutes in January 2010 as a partial solar eclipse became momentarily visible across part of planet Earth. In this single exposure image, meticulous planning enabled careful photographers to capture the partially eclipsed Sun well posed just above the ancient ruins of the Temple of Poseidon in Sounio, Greece. Unexpectedly, clouds covered the top of the Sun, while a flying bird was caught in flight just to the right of the eclipse. At its fullest extent from some locations, the Moon was seen to cover the entire middle of the Sun, leaving the surrounding ring of fire of an annular solar eclipse.

Image Credit & Copyright: Chris Kotsiopoulos & Anthony Ayiomamitis

Explanation from: http://apod.nasa.gov/apod/ap100118.html

PLEASE SHARE

Tweet

Read More

Earth's Shadow

The dark, inner shadow of planet Earth is called the umbra. Shaped like a cone extending into space, the umbra has a circular cross section that can be most easily seen during a lunar eclipse. For example, in August 2008, the Full Moon slid across the northern edge of the umbra. Entertaining moon watchers throughout Earth's eastern hemisphere, the lunar passage created a deep but partial lunar eclipse. This composite image uses successive pictures recorded during the eclipse from Athens, Greece to trace out a large part of the umbra's curved edge. The result nicely illustrates the relative size of the umbra's cross section at the distance of the Moon, as well as the Moon's path through the Earth's shadow.

Image Credit & Copyright: Anthony Ayiomamitis
Explanation from: http://apod.nasa.gov/apod/ap080820.html

PLEASE SHARE

Tweet

Read More

Shooting a Laser at the Galactic Centre

The sky above Paranal on 21 July 2007. Two 8.2-m telescopes of ESO's VLT are seen against the wonderful backdrop of the myriad of stars and dust that makes the Milky Way. Just above Yepun, Unit Telescope number 4, the Small Magellanic Cloud - a satellite galaxy of the Milky Way - is shining. A laser beam is coming out of Yepun, aiming at the Galactic Centre. It is used to obtain images that are free from the blurring effect of the atmosphere. On this image, the laser beam looks slightly artificial. This is a side effect due to saturation caused by the long exposure time. Planet Jupiter is seen as the brightest object on the upper right, next to the star Antares. Image taken by ESO astronomer Yuri Beletsky.

Image Credit: ESO/Yuri Beletsky
Explanation from: http://www.eso.org/public/images/eso0733b/

PLEASE SHARE

Tweet

Read More

Sunrise over Cape Sounion

The Sun is a moving target. Its annual motion through planet Earth's sky tracks north and south, from solstice to solstice, as the seasons change. On December 21st, the solstice marking the first day of winter in the northern hemisphere and summer in the south, the Sun rose at its southernmost point along the eastern horizon. Earlier December, 2009, looking toward the Aegean Sea from a well-chosen vantage point at Cape Sounion, Greece, it also rose in this dramatic scene. In the foreground lies the twenty-four hundred year old Temple of Poseidon.

Image Credit & Copyright: Anthony Ayiomamitis
Explanation from: http://apod.nasa.gov/apod/ap091223.html

PLEASE SHARE

Tweet

Read More

Total Lunar Eclipse and Lightning

Icaria, Greece

June 15, 2011

Image Credit & Copyright: Chris Kotsiopoulos

PLEASE SHARE

Tweet

Read More

Asperatus Clouds over New Zealand

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. This image, taken above Hanmer Springs in Canterbury, New Zealand, in 2005, shows great detail partly because sunlight illuminates the undulating clouds from the side.

Image Credit & Copyright: Witta Priester
Explanation: http://apod.nasa.gov/apod/ap130227.html

PLEASE SHARE

Tweet

Read More

Supercell

A supercell is a thunderstorm that is characterized by the presence of a mesocyclone: a deep, persistently rotating updraft. For this reason, these storms are sometimes referred to as rotating thunderstorms. Of the four classifications of thunderstorms (supercell, squall line, multi-cell, and single-cell), supercells are the overall least common and have the potential to be the most severe. Supercells are often isolated from other thunderstorms, and can dominate the local climate up to 32 kilometres (20 mi) away.

PLEASE SHARE

Tweet

Read More

Alaskan Moondogs

Moonlight illuminates a snowy scene in this night land and skyscape made on January 17, 2013 from Lower Miller Creek, Alaska, USA. Overexposed near the mountainous western horizon is the first quarter Moon itself, surrounded by an icy halo and flanked left and right by moondogs. Sometimes called mock moons, a more scientific name for the luminous apparitions is paraselenae (plural). Analogous to a sundog or parhelion, a paraselene is produced by moonlight refracted through thin, hexagonal, plate-shaped ice crystals in high cirrus clouds. As determined by the crystal geometry, paraselenae are seen at an angle of 22 degrees or more from the Moon. Compared to the bright lunar disk, paraselenae are faint and easier to spot when the Moon is low.

Image Credit & Copyright: Sebastian Saarloos
Explanation: http://apod.nasa.gov/apod/ap130126.html

PLEASE SHARE

Tweet

Read More

A Lenticular Cloud over New Zealand

What's happening above those mountains? Several clouds are stacked up into one striking lenticular cloud. Normally, air moves much more horizontally than it does vertically. Sometimes, however, such as when wind comes off of a mountain or a hill, relatively strong vertical oscillations take place as the air stabilizes. The dry air at the top of an oscillation may be quite stratified in moisture content, and hence forms clouds at each layer where the air saturates with moisture. The result can be a lenticular cloud with a strongly layered appearance. This picture was taken in 2002 looking southwest over the Tararua Range mountains from North Island, New Zealand.

Image Credit & Copyright: Chris Picking
Explanation from: http://apod.nasa.gov/apod/ap090121.html

PLEASE SHARE

Tweet

Read More

Sunrise Solstice at Stonehenge

This picture was taken during the week of the 2008 summer solstice at Stonehenge in United Kingdom, and captures a picturesque sunrise involving fog, trees, clouds, stones placed about 4,500 years ago, and a 5 billion year old large glowing orb. Even given the precession of the Earth's rotational axis over the millennia, the Sun continues to rise over Stonehenge in an astronomically significant way.

Image Credit & Copyright: Max Alexander, STFC, SPL
Explanation from: http://apod.nasa.gov/apod/ap100621.html

PLEASE SHARE

Tweet

Read More

NASA's SDO Observes Fast-Growing Sunspot

As magnetic fields on the sun rearrange and realign, dark spots known as sunspots can appear on its surface. Over the course of Feb. 19-20, 2013, scientists watched a giant sunspot form in under 48 hours. It has grown to over six Earth diameters across but its full extent is hard to judge since the spot lies on a sphere not a flat disk.

The spot quickly evolved into what's called a delta region, in which the lighter areas around the sunspot, the penumbra, exhibit magnetic fields that point in the opposite direction of those fields in the center, dark area. This is a fairly unstable configuration that scientists know can lead to eruptions of radiation on the sun called solar flares.

Image Credit: NASA/SDO/AIA/HMI/Goddard Space Flight Center
Explanation from: http://www.nasa.gov/mission_pages/sdo/news/fastgrowing-sunspot.html

PLEASE SHARE

Tweet

Read More