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ikenbot: Watch Live Now: Mars Makes Close Approach To Earth The impressive view of the Red Planet will show large features on its surface as well as its polar caps. It will also include commentary by Slooh’s Patrick Paolucci, Astronomy Magazine columnist Bob Berman, and some special guests.

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bonierrope2: A black hole is a region of spacetime from which nothing, not even light, can escape. The theory of general relativity predicts that a sufficiently compact mass will deform spacetime to form a black hole. Around a black hole there is a mathematically defined surface called an event horizon that marks the point of no return. It is called “black” because it absorbs all the light that hits the horizon, reflecting nothing, just like a perfect black body in thermodynamics. Quantum mechanics predicts that black holes emit radiation like a black body with a finite temperature. This temperature is inversely proportional to the mass of the black hole, making it difficult to observe this radiation for black holes of stellar mass or greater. Objects whose gravity field is too strong for light to escape were first considered in the 18th century by John Michell and Pierre-Simon Laplace. The first modern solution of general relativity that would characterize a black hole was found by Karl Schwarzschild in 1916, although its interpretation as a region of space from which nothing can escape was not fully appreciated for another four decades. Long considered a mathematical curiosity, it was during the 1960s that theoretical work showed black holes were a generic prediction of general relativity. The discovery of neutron stars sparked interest in gravitationally collapsed compact objects as a possible astrophysical reality. Black holes of stellar mass are expected to form when very massive stars collapse at the end of their life cycle. After a black hole has formed it can continue to grow by absorbing mass from its surroundings. By absorbing other stars and merging with other black holes, supermassive black holes of millions of solar masses may form. There is general consensus that supermassive black holes exist in the centers of most galaxies. In particular, there is strong evidence of a black hole of more than 4 million solar masses at the center of our galaxy, the Milky Way. Despite its invisible interior, the presence of a black hole can be inferred through its interaction with other matter and with light and other electromagnetic radiation. From stellar movement, the mass and location of an invisible companion object can be calculated; in a number of cases the only known object capable of meeting these criteria is a black hole. Astronomers have identified numerous stellar black hole candidates in binary systems by studying the movement of their companion stars in this way.

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the-star-stuff: 1 in 8 Chance of Catastrophic Solar Megastorm by 2020 The Earth has a roughly 12 percent chance of experiencing an enormous megaflare erupting from the sun in the next decade. This event could potentially cause trillions of dollars’ worth of damage and take up to a decade to recover from. Such an extreme event is considered to be relatively rare. The last gigantic solar storm, known as the Carrington Event, occurred more than 150 years ago and was the most powerful such event in recorded history. That a rival to this event might have a greater than 10 percent chance of happening in the next 10 years was surprising to space physicist Pete Riley, senior scientist at Predictive Science in San Diego, California, who published the estimate in Space Weather on Feb. 23. “Even if it’s off by a factor of two, that’s a much larger number than I thought,” he said. Earth’s sun goes through an 11-year cycle of increased and decreased activity. During solar maximum, it’s dotted with many sunspots and enormous magnetic whirlwinds erupt from its surface. Occasionally, these flares burst outward from the sun, spewing a mass of charged particles out into space. Small solar flares happen quite often whereas very large ones are infrequent, a mathematical distribution known as a power law. Riley was able to estimate the chance of an enormous solar flare by looking at historical databases and calculating the relation between the size and occurrence of solar flares. [continue reading…]

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sagansense: Michael Khan made this montage of the Moon from the images he took from January 31 to February 6, 2012 in Darmstadt, Germany. “The sky is much clearer today that it was yesterday. Due to libration effects, regions beyond 90 deg Western longitude are visible. Conversely, the lunar surface near 90 deg Eastern longitude is not observable, which is why the Mare Crisium is now so close to the limb.” Here are some of the specs Michael provided: Telescope: ED apochromatic refractor, focal length 420 mm, aperture 70 mm. Camera: Unmodified Canon 1000d.

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kqedscience: Omega Centauri Looks Radiant in Infrared

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rvlvr: The first daguerreotype of a solar eclipse The first correctly-exposed photograph of the solar corona was made during the total phase of the solar eclipse of 28 July 1851 at Königsberg (now Kaliningrad) by a local daguerreotypist named Berkowski. Berkowski observed at the Royal Observatory following a proposal by its director A. Busch. A small refracting telescope (D = 6.1 cm, f = 81.2 cm) was attached to the hour drive of the 15.8-cm Fraunhofer heliometer, and a 84-s exposure was taken shortly after the beginning of totality. After the eclipse, Busch (who did not observe the eclipse at Königsberg but at Rixhöft), published some details about the daguerreotype (without mentioning Berkowski’s first name) and ordered a local artist (R. Trossin) to make an enlarged steel engraving from the daguerreotype plate. On the original plate the moon’s diameter is 7.85 mm, and at least 5 prominences are well visible on the limb of the sun. Later Berkowski himself made some daguerreotype reproductions from his original plate.

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zombieelephant: NASA plans to drop nearly $310 million from the budget for its Planetary Science division in 2013, a 20 percent cut that affects future missions to Mars, lunar science, and the study of the outer planets. The cuts are part of a $17.7 billion budget request NASA unveiled Monday a mere 0.3 percent cut from the 17.8 billion Congress approved in November for 2012. But it represents a 5 percent cut from the $18.7 billion President Barack Obama penciled in for 2013 in the five-year budget he sent to Congress this time last year. And it leaves NASA funded at its lowest level in four years, forcing the space agency to juggle priorities and “devastating planetary science,” said Bill Nye, CEO of space exploration group The Planetary Society. “Science is the part of NASA that’s actually conducting interesting and scientifically important missions,” Nye said in a statement about the 2013 budgetary figures. “Spacecraft sent to Mars, Saturn, Mercury, the Moon, comets, and asteroids have been making incredible discoveries, with more to come from recent launches to Jupiter, the Moon, and Mars.” “The country needs more of these robotic space exploration missions, not less.”