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Explanation: Where are all of these meteors coming from? In terms of direction on the sky, the pointed answer is the constellation of Perseus. That is why the meteor shower that peaked over the past few days is known as the Perseids -- the meteors all appear to come from a radiant toward Perseus. Three dimensionally, however, sand-sized debris expelled from Comet Swift-Tuttle follows a well-defined orbit about our Sun, and the part of the orbit that approaches Earth is superposed in front of the Perseus. Therefore, when Earth crosses this orbit, the radiant point of falling debris appears in...

Explanation: Are asteroids dangerous? Some are, but the likelihood of a dangerous asteroid striking the Earth during any given year is low. Because some past mass extinction events have been linked to asteroid impacts, however, humanity has made it a priority to find and catalog those asteroids that may one day affect life on Earth. Pictured above are the orbits of the over 1,000 known Potentially Hazardous Asteroids (PHAs). These documented tumbling boulders of rock and ice are over 140 meters across and will pass within 7.5 million kilometers of Earth -- about 20 times the distance to the Moon....

Explanation: If not perfect, then this spiral galaxy is at least one of the most photogenic. An island universe of about 100 billion stars, 32 million light-years away toward the constellation Pisces, M74 presents a gorgeous face-on view. Classified as an Sc galaxy, the grand design of M74's graceful spiral arms are traced by bright blue star clusters and dark cosmic dust lanes. Constructed from image data recorded in 2003 and 2005, this sharp composite is from the Hubble Space Telescope's Advanced Camera for Surveys. Spanning about 30,000 light-years across the face of M74, it includes exposures recording emission from...

Look for the 2013 Perseid meteor shower to be at its prolific best from late late August 11 until dawn August 12! Great times to watch: after midnight and before dawn on August 11, 12 or 13. We give the nod to Monday, August 12 – in the hours between midnight and dawn. But any of these mornings should be fine for watching this year’s Perseid shower. At dusk and early evening on August 11, the waxing crescent moon shines between the planet Venus and the star Spica. The planet Saturn is found above Spica. The Perseids are a summertime...

More than 100,000 people around the world have applied to be the first to make a one-way trip to Mars, according to organisers of a prospective mission. The private Dutch-based Mars One project is proposing to select a group of 40 would-be civilian astronauts this year, aiming to send four of them on a no-return journey to to the red planet in 2022. Experts have questioned both the financial and practical viability of the mission, but that hasn't stopped people signing up in droves, including 30,000 Americans, CNN reported. The estimated cost for the initial mission is $6 billion (£3.87...

Scientists have long tried to figure out what causes the ebb and flow of ice ages. New data suggests a novel explanation for why the mile-thick blankets of ice retreat so quickly: They become too heavy. For the last 900,000 years, mile-thick ice sheets have waxed and waned in the Northern Hemisphere with remarkable regularity – building over periods of about 100,000 years and retreating in the space of only a few thousand years, only to repeat the cycle. Now, a team of scientists from Japan, the US, and Switzerland suggests that the North American continent is the breeding ground...

Explanation: The two bright meteors flashing through this night skyscape from August 7 are part of the ongoing Perseid meteor shower. In the direction indicated by both colorful streaks, the shower's radiant in the eponymous constellation Perseus is at the upper right. North star Polaris, near the center of all the short, arcing star trails is at the upper left. But also named for its pose against the sky, the monastery built on the daunting sandstone cliffs in the foreground is part of Meteora. A World Heritage site, Meteora is a historic complex of lofty monasteries located near Kalabaka in...

Explanation: Medieval Albrechtsberg castle is nestled in trees near the northern bank of the river Pielach and the town of Melk, Austria. In clearing night skies on August 12, 2012 it stood under constellations of the northern summer, including Aquarius, Aquila, and faint, compact Delphinus (above and right of center) in this west-looking skyview. The scene also captures a bright meteor above the castle walls. Part of the annual perseid meteor shower, its trail points back toward the heroic constellation Perseus high above the horizon in the early morning hours. Entering the atmosphere at about 60 kilometers per second, perseid...

The Blackbody force is a newly discovered force that attracts atoms and molecules to hot, opaque objects emitting blackbody radiation. Under certain circumstances, the new force is stronger than gravity.

The 2013 Perseid meteor shower will peak overnight between Aug. 11 and 12, and Aug. 12 and 13, Cooke wrote, adding that NASA's fireball network is already catching more Perseids as the time of peak activity nears. The Perseid meteor shower occurs each year in mid-August when the Earth passes through a stream of dusty debris from the Comet Swift-Tuttle, which takes about 130 years to orbit the sun. The comet last passed through the inner solar system in December 1992.

Black holes can be described by just two fundamental characteristics: mass and spin. Astronomers have been able to measure the objects’ mass for decades, by looking for gravitational effects on the orbits of nearby stars. But measuring spin, which records the angular momentum of the matter that falls into the holes, has proved troublesome, particularly for the supermassive black holes that lie at the centres of galaxies. No light emanates from the black holes’ spinning event horizons, so astronomers instead look for proxies that emit X-rays, such as the swirling disks of matter that feed into some holes. Such indirect...

Explanation: Similar in size and grand design to our own Milky Way, spiral galaxy NGC 3370 lies about 100 million light-years away toward the constellation Leo. Recorded here in exquisite detail by the Hubble Space Telescope's Advanced Camera for Surveys, the big, beautiful face-on spiral does steal the show, but the sharp image also reveals an impressive array of background galaxies in the field, strewn across the more distant Universe. Looking within NGC 3370, the image data has proved sharp enough to study individual pulsating stars known as Cepheids that can be used to accurately determine this galaxy's distance. NGC...

Explanation: What's going on behind that mountain? Quite a bit. First of all, the mountain itself, named Kirkjufell, is quite old and located in western Iceland near the town of Grundarfj%C3%B6r%C3%B0ur. In front of the steeply-sloped structure lies a fjord that had just begun to freeze when the above image was taken -- in mid-December of 2012. Although quite faint to the unaided eye, the beautiful colors of background aurorae became quite apparent on the 25-second exposure. What makes Geminids meteor shower -- meteors that might not have been evident were the aurora much brighter. Far in the distance, on...

A team from the University of Birmingham recently announced an astronomical discovery in Scotland marking the beginnings of recorded time. Announced last month in the Journal of Internet Archaeology, the Mesolithic monument consists of a series of pits near Aberdeenshire, Scotland. Estimated to date from 8,000 B.C., this 10,000 year old structure would pre-date calendars discovered in the Fertile Crescent region of the Middle East by over 5,000 years.

Explanation: Strange shapes and textures can be found in neighborhood of the Cone Nebula. The unusual shapes originate from fine interstellar dust reacting in complex ways with the energetic light and hot gas being expelled by the young stars. The brightest star on the right of the above picture is S Mon, while the region just below it has been nicknamed the Fox Fur Nebula for its color and structure. The blue glow directly surrounding S Mon results from reflection, where neighboring dust reflects light from the bright star. The red glow that encompasses the whole region results not only...

The flip-flopping of the Sun’s magnetic field takes place at the peak of each solar activity cycle when the Sun’s internal magnetic dynamo reorients itself. When the field reversal happens, the magnetic field weakens, then dies down to zero before emerging again with a reversed polarity. While this is not a catastrophic event, the reversal will have effects, said solar physicist Todd Hoeksema, the director of Stanford University’s Wilcox Solar Observatory, who monitors the Sun’s polar magnetic fields. “This change will have ripple effects throughout the Solar System,” he said.

WeChooseTheMoon.org was designed to celebrate the Fortieth anniversary of the Apollo 11 Lunar landing by developing an interactive recreation of the event. The site uses Flash to mesh archival video, audio, & photos into an experience that will make you feel as if you too had walked on the moon that day.

Low-mass Jupiter-like exoplanet challenges planetary formation theory Astronomers have detected a low-mass giant planet that challenges existing theories about how bigger worlds are formed.Artist's impression ... the Jupiter-like low-mass exoplanet GJ 504b The Jupiter-sized world, dubbed GJ 504b, was found much further out in its star's orbit than a planet its size should have been, if you go by existing planet-formation theory.GJ 504b weighs in at around four times Jupiter's mass, and is the lowest mass exoplanet* to be imaged orbiting a Sun-like star using direct imaging techniques.Given its similarity to Jupiter's size, NASA boffins were surprised to find that...

About to go to space? Better postpone your trip The solar magnetic field will completely "flip" within the next three or four months, according to NASA.The dramatic-sounding event happens every 11 years. The Sun's magnetic activity follows a cycle, and as it reaches a maximum the poles weaken, reversing polarity. In June last year, the Sun's northern polar field became more positively charged than the southern polar field - what's called a "reversal" of polarity. What's called a "flip" is considered to have taken place when the both fields change polarity. The Sun's magnetic field is weak but extends far...

August 5, 2013 – SIBERIA - Having an official task to draw up a geological map of the region, a young geologist ended up running into something so unique, outstanding and mysterious that it would still puzzle scientists more than six decades later – the Patomskiy Crater. A host of theories have been put forward in the intervening years: that the crater was created by an ancient civilization, or by prisoners at a top secret Stalin labor camp, or by volcanic activity, or by a meteorite, or by an underground hydrogen explosion, or by a UFO. And even more...

August 5, 2013: Something big is about to happen on the sun. According to measurements from NASA-supported observatories, the sun's vast magnetic field is about to flip. "It looks like we're no more than 3 to 4 months away from a complete field reversal," says solar physicist Todd Hoeksema of Stanford University. "This change will have ripple effects throughout the solar system."

Explanation: What it would look like to leave planet Earth? Such an event was recorded visually in great detail by the MESSENGER spacecraft as it swung back past the Earth, eight years ago, on its way in toward the planet Mercury. Earth can be seen rotating in this time-lapse video, as it recedes into the distance. The sunlit half of Earth is so bright that background stars are not visible. The robotic MESSENGER spacecraft is now in orbit around Mercury and has recently concluded the first complete map of the surface. On occasion, MESSENGER has continued to peer back at...

The first interesting form is the scorpion, which might first be thought to represent is known as Scorpius, but this does not appear to be the case.  This is due to the presence of the three birds to the middle right (A, B, C), these three most clearly correspond to the “Summer Triangle� stars, the three birds, one represented by each star: Cygnus, Aquila (aka Vultur volans), and Vultur cadens (Lyra).  The shape of the Aquila constellations holds the same general appearance as bird A, the angle of the Cygnus stars matches the shape of the body of bird B,...

Explanation: Like the downtown area of your favorite city and any self-respecting web site ... Io's surface is constantly under construction. This moon of Jupiter holds the distinction of being the Solar System's most volcanically active body -- its bizarre looking surface continuously formed and reformed by lava flows. Generated using 1996 data from NASA's Galileo spacecraft, this high resolution composite image is centered on the side of Io that always faces away from Jupiter. It has been enhanced to emphasize Io's surface brightness and color variations, revealing features as small as 1.5 miles across. The notable absence of impact...

Lots of people talking about this article in the UK daily Mail:A near miss for Earth: Solar flare that could have knocked out power, cars and phones came so close two weeks ago Earth has narrowly missed electromagnetic pulses caused by solar flaresIf they had hit, the pulses could have knocked out electrical equipment over continent-scale regions An electromagnetic pulse that could have knocked electrical equipment over continent-scale regions barely missed Earth two weeks ago, it has been revealed.Source: (h/t Jack Simmons)http://www.dailymail.co.uk/sciencetech/article-2382527/A-near-miss-Earth-Devastating-electromagnetic-pulses-knocked-power-cars-phones-occured-weeks-ago.htmlBut, not so fast…NASA’s Dr. Tony Phillips of Spaceweather.com writes: Many readers are asking about a report in the...

Explanation: A careful look at this colorful cosmic snapshot reveals a surprising number of galaxies both near and far toward the constellation Ursa Major. The most striking is NGC 3718, the warped spiral galaxy near picture center. NGC 3718's spiral arms look twisted and extended, mottled with young blue star clusters. Drawn out dust lanes obscure its yellowish central regions. A mere 150 thousand light-years to the right is another large spiral galaxy, NGC 3729. The two are likely interacting gravitationally, accounting for the peculiar appearance of NGC 3718. While this galaxy pair lies about 52 million light-years away, the...

There’s a potential “cometary graveyard” of inactive comets in our solar system wandering between Mars and Jupiter, a new Colombian research paper says. This contradicts a long-standing view that comets originate on the fringes of the solar system, in the Oort Cloud.

An amateur astronomer has become the first person to capture a massive lightning strike ‘into space’ above the British Isles. The atmospheric phenomena, known as sprites, had never been recorded in the UK before an amateur astronomer in East Yorkshire managed to take the photographic first. Richard Kacerek, 33, spotted the sprite – caused by an upward lightning discharge five miles east of Hull – and has sparked excitement in the scientific community with his image. An amateur astronomer has become the first person to capture a massive lightning strike ‘into space’ (pictured) above the British Isles An amateur astronomer...

Explanation: This intriguing monument can be found in Taiwan between the cities of Hualian and Taitong. Split into two sides, it straddles a special circle of latitude on planet Earth, near 23.5 degrees north, known as the Tropic of Cancer. Points along the Tropic of Cancer are the northernmost locations where the Sun can pass directly overhead, an event that occurs once a year during the northern hemisphere's summer solstice. The latitude that defines the Tropic of Cancer corresponds to the tilt of planet Earth's rotation axis with respect to its orbital plane. The name refers to the zodiacal constellation...

Explanation: The Great Spiral Galaxy in Andromeda (aka M31), a mere 2.5 million light-years distant, is the closest large spiral to our own Milky Way. Andromeda is visible to the unaided eye as a small, faint, fuzzy patch, but because its surface brightness is so low, casual skygazers can't appreciate the galaxy's impressive extent in planet Earth's sky. This entertaining composite image compares the angular size of the nearby galaxy to a brighter, more familiar celestial sight. In it, a deep exposure of Andromeda, tracing beautiful blue star clusters in spiral arms far beyond the bright yellow core, is combined...

BORREGO STARDANCE from Sunchaser Pictures "The Trippiest Time Lapse Video We've Ever Seen" -- POPULAR SCIENCE [O]ur next adventure takes us to the desert town of Borrego Springs, California -- a remarkable hidden gem surrounded by the 600,000 acre Anza-Borrego Desert State Park. Just three hours south of Los Angeles, this unspoiled landscape shines not only for its natural wonders, but for the absolutely amazing, enormous metal sculptures left behind by local business leader Dennis Avery. Dragons, Dinosaurs, Giant Scorpions, Wooly Mammoths, and much more!

Explanation: How has the surface temperature of Earth been changing? To help find out, Earth scientists collected temperature records from over 1000 weather stations around the globe since 1880, and combined them with modern satellite data. The above movie dramatizes the result showing 130 years of planet-wide temperature changes relative to the local average temperatures in the mid-1900s. In the above global maps, red means warmer and blue means colder. On average, the display demonstrates that the temperature on Earth has increased by nearly one degree Celsius over the past 130 years, and many of the warmest years on record...

Two EMP experts told Secrets that the EMP flashed through earth's typical orbit around the sun about two weeks before the planet got there. "The world escaped an EMP catastrophe," said Henry Cooper, who lead strategic arms negotiations with the Soviet Union under President Reagan, and who now heads High Frontier, a group pushing for missile defense. "There had been a near-miss about two weeks ago, a Carrington-class coronal mass ejection crossed the orbit of the Earth and basically just missed us," said Peter Vincent Pry, who served on the Congressional EMP Threat Commission from 2001-2008. He was referring to...

A press release out yesterday about a recent paper on Comet ISON has caused a mild uproar across the astronomy-minded social media outlets and some websites. The article issued from the Physics & Astrophysics Computation Group (FACOM) at the University of Antioquia in Medellin, Colombia is titled “Comet Of The Century? Not Yet! Comet C/2012 S1 ISON Has Fizzled Completely And May Disintegrate At Or Before Reaching Perihelion.” The article had professional astronomers and comet enthusiasts alike shaking their heads in disbelief. ... In the paper, Ferrin reaches some of his conclusions comparing ISON to Comet Honig (2002 O4), the...

Explanation: In 1787, astronomer William Herschel discovered the Eskimo Nebula. From the ground, NGC 2392 resembles a person's head surrounded by a parka hood. In 2000, the Hubble Space Telescope imaged the Eskimo Nebula in visible light, while the nebula was imaged in X-rays by the Chandra X-ray Observatory in 2007. The above combined visible-X ray image, with X-rays emitted by central hot gas and shown in pink, was released last week. From space, the nebula displays gas clouds so complex they are not fully understood. The Eskimo Nebula is clearly a planetary nebula, and the gas seen above composed...

Explanation: This is not a solar eclipse. Pictured above is a busy vista of moons and rings taken at Saturn. The large circular object in the center of the image is Titan, the largest moon of Saturn and one of the most intriguing objects in the entire Solar System. The dark spot in the center is the main solid part of the moon. The bright surrounding ring is atmospheric haze above Titan, gas that is scattering sunlight to a camera operating onboard the robotic Cassini spacecraft. Cutting horizontally across the image are the rings of Saturn, seen nearly edge on....

Scientists have spotted swirling patterns in the radiation lingering from the big bang, the so-called cosmic microwave background (CMB). The observation itself isn't Earth-shaking, as researchers know that these particular swirls or "B-modes" originated in conventional astrophysics, but the result suggests that scientists are closing in on a much bigger prize: B-modes spawned by gravity waves that rippled through the infant universe. That observation would give them a direct peek into the cosmos' first fraction of a second and possibly shed light on how it all began."I see it as a big step forward," says Charles Bennett, a cosmologist...

A space telescope aimed at the sun has spotted a gigantic hole in the solar atmosphere — a dark spot that covers nearly a quarter of our closest star, spewing solar material and gas into space. The so-called coronal hole over the sun's north pole came into view between July 13 and 18 and was observed by the Solar and Heliospheric Observatory, or SOHO. NASA released a video of the sun hole as seen by the SOHO spacecraft, showing the region as a vast dark spot surrounded by solar activity. Coronal holes are darker, cooler regions of the sun's atmosphere,...

The Yarlung-Tsangpo River in southern Asia drops rapidly through the Himalaya Mountains on its way to the Bay of Bengal, losing about 7,000 feet of elevation through the precipitously steep Tsangpo Gorge. For the first time, scientists have direct geochemical evidence that the 150-mile long gorge, possibly the world's deepest, was the conduit by which megafloods from glacial lakes, perhaps half the volume of Lake Erie, drained suddenly and catastrophically through the Himalayas when their ice dams failed at times during the last 2 million years... In this case, the water moved rapidly through bedrock gorge, carving away the base...

Explanation: Is this one galaxy or two? This question came to light in 1950 when astronomer Art Hoag chanced upon this unusual extragalactic object. On the outside is a ring dominated by bright blue stars, while near the center lies a ball of much redder stars that are likely much older. Between the two is a gap that appears almost completely dark. How Hoag's Object formed remains unknown, although similar objects have now been identified and collectively labeled as a form of ring galaxy. Genesis hypotheses include a galaxy collision billions of years ago and the gravitational effect of a...

The title sort of gives it away, but did you know that there is an online archive that contains high-resolution film scans from every Apollo mission? The gallery contains all of the incredible photos taken during each of the missions — from Apollo 1 all the way through Apollo 17 — with some 1,000+ photos from Apollo 11 alone. The archive, officially the Apollo Image Gallery, was put together by the Project Apollo Archive by scanning photographs provided by the NASA History Office, Kennedy Space Center and Johnson Space Center. Since all of these images were taken by NASA astronauts...

Explanation: Storm clouds do sometimes come to Chile's Atacama desert, known as the driest place on Earth. These washed through the night sky just last month during the winter season, captured in this panoramic view. Drifting between are cosmic clouds more welcome by the region's astronomical residents though, including dark dust clouds in silhouette against the crowded starfields and nebulae of the central Milky Way. Below and right of center lies the Large Magellanic Cloud, appropriately named for its appearance in starry southern skies. City lights about 200 kilometers distant still glow along the horizon at the right, while bright...

NASA's latest solar observatory is online and sending back pictures of the Sun's inner atmosphere that could help answer some of the essential questions about our closest star and its effects on Earth.IRIS opens up "My teachers at the University of Chicago instilled in me a real wonder at the mystery of the Sun," said John Grunsfeld, associate administrator of the Science Mission Directorate at NASA at a press conference on Thursday."It's the star for which everything that happens here on Earth depends on," Grunsfeld said, "and there are some real deep mysteries in the Sun and how it works,...

Explanation: Like an illustration in a galactic Just So Story, the Elephant's Trunk Nebula winds through the emission nebula and young star cluster complex IC 1396, in the high and far off constellation of Cepheus. Of course, the cosmic elephant's trunk is over 20 light-years long. This composite was recorded through narrow band filters that transmit the light from ionized hydrogen, sulfur, and oxygen atoms in the region. The resulting image highlights the bright swept-back ridges that outline pockets of cool interstellar dust and gas. Such embedded, dark, tendril-shaped clouds contain the raw material for star formation and hide protostars...

Van Allen belts accelerate their own particles rather than just trapping them. The two concentric rings of high-speed particles that encircle the Earth are finally giving up the secrets of their origin — 55 years after their discovery. Two NASA probes have found evidence that the Van Allen belts, as the rings are known, are responsible for accelerating the particles, rather than collecting energetic particles that originated elsewhere. Space scientists think that their latest findings1 could also account for the even more energetic belts circling Saturn and Jupiter, as well as high-energy radiation associated with worlds beyond the Solar System...

Explanation: The beautiful Trifid Nebula is a cosmic study in 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 dust lanes, lends the Trifid its popular name. But in this sharp, colorful scene,...

Explanation: Each panel shows one day. With 360 movie panels, the sky over (almost) an entire year is shown in time lapse format as recorded by a video camera on the roof of the Exploratorium museum in San Francisco, California. The camera recorded an image every 10 seconds from before sunrise to after sunset and from mid-2009 to mid-2010. A time stamp showing the local time of day is provided on the lower right. The videos are arranged chronologically, with July 28 shown on the upper left, and January 1 located about about half way down. Although every day lasts...

Athletes who top the podium on Feb. 15, 2014 will receive special medals with pieces of the Chelyabinsk meteor that broke up over the remote Russian community on that day in 2013, according to media reports.

A comet that could put on a dazzling show when it zooms through the inner solar system later this year is already blasting out huge amounts of gas and dust, new observations by a NASA spacecraft show. ... The comet, which is about 3 miles (5 km) wide, is cruising toward a close encounter with the sun on Nov. 28, when it will skim just 724,000 miles (1.16 million km) above the solar surface. ISON could blaze up dramatically around this time, perhaps shining as brightly as the full moon in the sky, researchers say. But there's no guarantee that...

Explanation: In a cross-Solar System interplanetary first, our Earth was photographed during the same day from both Mercury and Saturn. Pictured on the left, Earth is the pale blue dot just below the rings of Saturn, as captured by the robotic Cassini spacecraft now orbiting the gas giant. Pictured on the right, the Earth-Moon system is seen against a dark background, as captured by the robotic MESSENGER spacecraft now orbiting Mercury. In the MESSENGER image, the Earth (left) and Moon (right) shine brightly with reflected sunlight. MESSENGER took the overexposed image last Friday as part of a search for small...