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Explanation: The colors of the solar system's innermost planet are enhanced in this tantalizing view, based on global image data from the Mercury-orbiting MESSENGER spacecraft. Human eyes would not discern the clear color differences but they are real none the less, indicating distinct chemical, mineralogical, and physical regions across the cratered surface. Notable at the upper right, Mercury's large, circular, tan colored feature known as the Caloris basin was created by an impacting comet or asteroid during the solar system's early years. The ancient basin was subsequently flooded with lava from volcanic activity, analogous to the formation of the lunar...

Is it too much to hope that even some catastrophists and peak-oil cultists will find it impossible to ignore the latest numbers? When the final figures for the fourth quarter of 2012 are in, the world will have a new crude oil production record: the total for the first three quarters was about 1 percent ahead of the 2011 total. This is a remarkable achievement for a commodity with annual output that now surpasses, for the first time ever, 4 billion metric tons and which has been, for decades, the largest source of fossil energy and the most valuable item...

Explanation: The alarmingly tall inhabitants of this small, snowy planet cast long shadows in bright moonlight. Of course, the snowy planet is actually planet Earth and the wide-angle mosaic, shown as a little planet projection, was recorded on February 25 during the long northern night of the Full Snow Moon. The second brightest celestial beacon is Jupiter, on the right above the little planet's horizon. Lights near Östersund, Sweden glow along the horizon, surrounding the snow covered lake Storsjön. The photographer reports that the journey out onto the frozen lake by sled to capture the evocative Full Snow Moon scene...

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,...

Explanation: Does it rain on the Sun? Yes, although what falls is not water but extremely hot plasma. An example occurred in mid-July 2012 after an eruption on the Sun that produced both a Coronal Mass Ejection and a moderate solar flare. What was more unusual, however, was what happened next. Plasma in the nearby solar corona was imaged cooling and falling back, a phenomenon known as coronal rain. Because they are electrically charged, electrons, protons, and ions in the rain were gracefully channeled along existing magnetic loops near the Sun's surface, making the scene appear as a surreal three-dimensional...

Explanation: Sometimes the Moon is a busy direction. Last week, for example, our very Moon passed in front of the planet Jupiter. While capturing this unusual spectacle from New South Wales, Australia, a quick-thinking astrophotographer realized that a nearby plane might itself pass in front of the Moon, and so quickly reset his camera to take a continuous series of short duration shots. As hoped, for a brief instant, that airplane, the Moon, and Jupiter were all visible in a single exposure, which is shown above. But the project was not complete -- a longer exposure was then taken to...

Politicians and businessmen are fond of talking about America's scientist shortage -- the dearth of engineering and lab talent that will inevitably leave us sputtering in the global economy. But perhaps it's time they start talking about our scientist surplus instead. I am by no means the first person to make this point. But I was compelled to try and illustrate it after reading a report from Inside Higher Ed on this weekend's gloomy gathering of the American Association for the Advancement of Science. In short, job prospects for young science Ph.D.'s haven't been looking so hot these last few...

Explanation: The Whirlpool Galaxy is a classic spiral galaxy. At only 30 million light years distant and fully 60 thousand light years across, M51, also known as NGC 5194, is one of the brightest and most picturesque galaxies on the sky. The above image is a digital combination of a ground-based image from the 0.9-meter telescope at Kitt Peak National Observatory and a space-based image from the Hubble Space Telescope highlighting sharp features normally too red to be seen. Anyone with a good pair of binoculars, however, can see this Whirlpool toward the constellation of the Hunting Dogs (Canes Venatici....

Explanation: A meteoroid fell to Earth on February 15, streaking some 20 to 30 kilometers above the city of Chelyabinsk, Russia at 9:20am local time. Initially traveling at about 20 kilometers per second, its explosive deceleration after impact with the lower atmosphere created a flash brighter than the Sun. This picture of the brilliant bolide (and others of its persistent trail) was captured by photographer Marat Ametvaleev, surprised during his morning sunrise session creating panoramic images of the nearby frosty landscape. An estimated 500 kilotons of energy was released by the explosion of the 17 meter wide space rock with...

Explanation: This remarkable self-portrait of NASA's Mars Curiosity Rover includes a sweeping panoramic view of its current location in the Yellowknife Bay region of the Red Planet's Gale Crater. The rover's flat, rocky perch, known as "John Klein", served as the site for Curiosity's first rock drilling activity. At the foot of the proud looking rover, a shallow drill test hole and a sample collection hole are 1.6 centimeters in diameter. The impressive mosaic was constructed using frames from the rover's Mars Hand Lens Imager (MAHLI) and Mastcam. Used to take in the panoramic landscape frames, the Mastcam is standing...

Explanation: How would you change the course of an Earth-threatening asteroid? One possibility - a massive spacecraft that uses gravity as a towline - is illustrated in this artist's vision of a gravitational tractor in action. In the hypothetical scenario worked out in 2005 by Edward Lu and Stanley Love at NASA's Johnson Space Center, a 20 ton nuclear-electric spacecraft tows a 200 meter diameter asteroid by simply hovering near the asteroid. The spacecraft's ion drive thrusters are canted away from the surface. Their slight but steady thrust would gradually and predictably alter the course of the tug and asteroid,...

Explanation: Why would clouds form a hexagon on Saturn? Nobody is sure. Originally discovered during the Voyager flybys of Saturn in the 1980s, nobody has ever seen anything like it anywhere else in the Solar System. If Saturn's South Pole wasn't strange enough with its rotating vortex, Saturn's North Pole might be considered even stranger. The bizarre cloud pattern is shown above in great detail by a recent image taken by the Saturn-orbiting Cassini spacecraft. This and similar images show the stability of the hexagon even 20+ years after Voyager. Movies of Saturn's North Pole show the cloud structure maintaining...

Explanation: Have you ever seen the planet Mercury? Because Mercury orbits so close to the Sun, it never wanders far from the Sun in Earth's sky. If trailing the Sun, Mercury will be visible low on the horizon for only a short while after sunset. If leading the Sun, Mercury will be visible only shortly before sunrise. So at certain times of the year an informed skygazer with a little determination can usually pick Mercury out from a site with an unobscured horizon. Above, a lot of determination has been combined with a little digital manipulation to show Mercury's successive...

Explanation: What in heaven's blazes is that? Thousands of people living near the Ural Mountains in Russia saw last Friday morning one of the more spectacular meteors of modern times streak across the sky. Forceful sound waves arrived at the ground minutes later, knocking people over and breaking windows for hundreds of kilometers. The above video is a compilation of several car dashcams and includes real time footage of the meteor rampaging, smoke trails drifting, shadows quickly shifting, and even the meteor's light reflecting off the back of a bus. The fireball is thought to have been caused by a...

Explanation: There it goes. That small spot moving in front of background stars in the above video is a potentially dangerous asteroid passing above the Earth's atmosphere. This past Friday, the 50-meter wide asteroid 2012 DA14 just missed the Earth, passing not only inside the orbit of the Moon, which is unusually close for an asteroid of this size, but also inside the orbit of geosynchronous satellites. Unfortunately, asteroids this big or bigger strike the Earth every 1000 years or so. Were 2012 DA14 to have hit the Earth, it could have devastated a city-sized landscape, or stuck an ocean...

An Indian teen has recently proposed a solution to an unsolved problem in mathematics. The 17-year-old young achiever, Rutvik Oza, a student of The H. B. Kapadia New High School, from Ahmedabad, Gujarat has now put a full stop to another open problem in the field of maths by providing a closed formula for the problem called Reve's Puzzle (also popularly known as the 4-peg Tower of Hanoi Problem). When asked about how was he feeling, "Thrilled! I really didn't realize at first that the problem that I had solved was an open problem in mathematics. It was only later...

Explanation: For now, Comet Lemmon (C/2012 F6a), and Comet PanSTARRS (C/2011 L4) are sweeping through southern skies. Lemmon's lime green coma and thin tail are near the left edge of this telephoto scene, a single frame from a timelapse video (vimeo here) recorded on February 12, tracking its motion against the background stars. Comet Lemmon's path brought it close to the line-of-sight to prominent southern sky treasures the Small Magellanic Cloud and globular cluster 47 Tucanae (right). Sporting a broader, whitish tail, Comet PanSTARRS appears in later video frames moving through the faint constellation Microscopium. Visible in binoculars and small...

‘Young’ black hole is nearby, NASA says; doorway to a new universe? Feb. 13, 2013 | 2:30 p.m. A supernova remnant may contain the most recent black hole formed in the Milky Way galaxy, according to NASA. (X-ray: NASA/CXC/MIT/L.Lopez et al; Infrared: Palomar; Radio: NSF/NRAO/VLA ) A supernova remnant may contain the most recent black hole formed in the Milky Way galaxy, according to NASA. (X-ray: NASA/CXC/MIT/L.Lopez et al; Infrared: Palomar; Radio: NSF/NRAO/VLA )Asteroid 2012 DA14 is bearing down on Earth, rattling nerves and making sci-fi fans’ eyes light up. But the cool science news doesn’t stop there. Researchers believe...

A Russian policeman works near an ice hole, said by the Interior Ministry department for Chelyabinsk region to be the point of impact of a meteor seen earlier in the Urals region, at lake Chebarkul some 80 kilometers (50 miles) west of Chelyabinsk February 15, 2013 (Reuters / Chelyabinsk region Interior Ministry) Russian scientists investigating the meteorite explosion in the Urals explained the nature of the event that caused havoc in the region. NASA said the shockwave force was equal to a 500-kiloton explosion – 30 times the Hiroshima blast.­The object was identified as a solitary 10-ton bolide by...

Explanation: Two dark shadows loom across the banded and mottled cloud tops of Jupiter in this sharp telescopic view. In fact, captured on January 3rd, about a month after the ruling gas giant appeared at opposition in planet Earth's sky, the scene includes the shadow casters. Visible in remarkable detail at the left are the large Galilean moons Ganymede (top) and Io. With the two moon shadows still in transit, Jupiter's rapid rotation has almost carried its famous Great Red Spot (GRS) around the planet's limb from the right. The pale GRS was preceded by the smaller but similar hued...