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Crowdsourcing the Hunt for Potentially Dangerous Asteroids
Image: Faulkes Telescope, Hawaii. Credit: ESA
What’s the best way to look for potentially hazardous asteroids? Get as many eyes on the sky as you can. That’s the impetus behind a new partnership between the European Space Agency and the Faulkes Telescope Project, which will encourage amateur astronomers to look for asteroids, as well as providing educational opportunities that will allow students to discover potentially dangerous space rocks, too.
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Fire, water, and ice
In the center of the picture is the Pleiades, the small cluster of bright stars. The bright object is the Moon, and to the lower right is Venus. If you look carefully, just above the horizon, lies Jupiter. To see it, start at the Pleiades, let your eyes move down and to the right to Venus, then keep going; Jupiter is in line with the clouds, just at the edge of the aurora itself.
Image credit: Helge Mortensen
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Top Ten Mysteries of the Universe
What are those burning questions about the cosmos that still baffle astronomers today?
1. What Are Fermi Bubbles?
No, this is not a rare digestive disorder. The bubbles are massive, mysterious structures that emanate from the Milky Ways center and extend roughly 20,000 light-years above and below the galactic plane. The strange phenomenon, first discovered in 2010, is made up of super-high-energy gamma-ray and X-ray emissions, invisible to the naked eye. Scientists have hypothesized that the gamma rays might be shock waves from stars being consumed by the massive black hole at the center of the galaxy.
2. Rectangular Galaxy
“Look, up in the sky! It’s a…rectangle?” Earlier this year, astronomers spotted a celestial body, roughly 70 million light-years away, with an appearance that is unique in the visible universe: The galaxy LEDA 074886 is shaped more or less like a rectangle. While most galaxies are shaped like discs, three-dimensional ellipses or irregular blobs, this one seems to have a regular rectangle or diamond-shaped appearance. Some have speculated that the shape results from the collision of two spiral-shaped galaxies, but no one knows for now.
3. The Moon’s Magnetic Field
One of the moon’s greatest mysteries—why only some parts of the crust seem to have a magnetic field—has intrigued astronomers for decades, even inspiring the buried mythical “monolith” in the novel and film 2001: A Space Odyssey. But some scientists finally think they may have an explanation. After using a computer model to analyze the moon’s crust, researchers believe the magnetism may be a relic of a 120-mile-wide asteroid that collided with the moon’s southern pole about 4.5 billion years ago, scattering magnetic material. Others, though, believe the magnetic field may be related to other smaller, more recent impacts.
4. Why Do Pulsars Pulse?
Pulsars are distant, rapidly spinning neutron stars that emit a beam of electromagnetic radiation at regular intervals, like a rotating lighthouse beam sweeping over a shoreline. Although the first one was discovered in 1967, scientists have for decades struggled to understand what causes these stars to pulse—and, for that matter, what causes pulsars to occasionally stop pulsing. In 2008, though, when one pulsar suddenly shut off for 580 days, scientists’ observations allowed them to determine that the “on” and “off” periods are somehow related to magnetic currents slowing down the stars’ spin. Astronomers are still at work trying to understand why these magnetic currents fluctuate in the first place.
5. What Is Dark Matter?
Astrophysicists are currently trying to observe the effects of dark energy [link to Fast Forward], which accounts for some 70 percent of the universe. But it’s not the only dark stuff in the cosmos: roughly 25 percent of it is made up of an entirely separate material called dark matter. Completely invisible to telescopes and the human eye, it neither emits nor absorbs visible light (or any form of electromagnetic radiation), but its gravitational effect is evident in the motions of galaxy clusters and individual stars. Although dark matter has proven extremely difficult to study, many scientists speculate that it might be composed of subatomic particles that are fundamentally different from those that create the matter we see around us.
6. Galactic Recycling
In recent years, astronomers have noticed that galaxies form new stars at a rate that would seem to consume more matter than they actually have inside them. The Milky Way, for example, appears to turn about one sun’s worth of dust and gas into new stars every year, but it doesn’t have enough spare matter to keep this up long-term. A new study of distant galaxies might provide the answer: Astronomers noticed gas that had been expelled by the galaxies flowing back in to the center. If the galaxies recycle this gas to produce new stars, it might be a piece of the puzzle in solving the question of the missing raw matter.
7. Where Is All the Lithium?
Models of the Big Bang indicate that the element lithium should be abundant throughout the universe. The mystery, in this case, is pretty straightforward: it doesn’t. Observations of ancient stars, formed from material most similar to that produced by the Big Bang, reveal amounts of lithium two to three times lower than predicted by the theoretical models. New research indicates that some of this lithium may be mixed into the center of stars, out of view of our telescopes, while theorists suggest that axions, hypothetical subatomic particles, may have absorbed protons and reduced the amount of lithium created in the period just after the Big Bang.
8. Is There Anybody Out There?
In 1961, astrophysicist Frank Drake devised a highly controversial equation: By multiplying together a series of terms relating to the probability of extraterrestrial life (the rate of star formation in the universe, the fraction of stars with planets, the fraction of planets with conditions suitable for life, etc.) he surmised that the existence of intelligent life on other planets is extremely likely. One problem: Roswell conspiracy theorists notwithstanding, we haven’t heard from any aliens to date. Recent discoveries of distant planets that could theoretically harbor life, though, have raised hopes that we might detect extraterrestrials if we just keep looking.
9. How Will the Universe End? [Warning, Potential Spoiler Alert!]
We now believe the universe started with the Big Bang. But how will it end? Based on a number of factors, theorists conclude that the fate of the universe could take one of several wildly different forms. If the amount of dark energy is not enough to resist the compressing force of gravity, the entire universe could collapse into a singular point—a mirror image of the Big Bang, known as the Big Crunch. Recent findings, though, indicate a Big Crunch is less likely than a Big Chill, in which dark energy forces the universe into a slow, gradual expansion and all that remains are burned-out stars and dead planets, hovering at temperatures barely above absolute zero. If enough dark energy is present to overwhelm all other forces, a Big Rip scenario could occur, in which all galaxies, stars and even atoms are torn apart.
10. Across the Multiverse
Theoretical physicists speculate that our universe may not be the only one of its kind. The idea is that our universe exists within a bubble, and multiple alternative universes are contained within their own distinct bubbles. In these other universes, the physical constants—and even the laws of physics—may differ drastically. Despite the theory’s resemblance to science fiction, astronomers are now looking for physical evidence: Disc-shaped patterns in the cosmic background radiation left over from the Big Bang, which could indicate collisions with other universes.](http://24.media.tumblr.com/tumblr_m3r1r8Bd2p1qbkzabo1_500.jpg)
Top Ten Mysteries of the Universe
What are those burning questions about the cosmos that still baffle astronomers today?
1. What Are Fermi Bubbles?
No, this is not a rare digestive disorder. The bubbles are massive, mysterious structures that emanate from the Milky Ways center and extend roughly 20,000 light-years above and below the galactic plane. The strange phenomenon, first discovered in 2010, is made up of super-high-energy gamma-ray and X-ray emissions, invisible to the naked eye. Scientists have hypothesized that the gamma rays might be shock waves from stars being consumed by the massive black hole at the center of the galaxy.
2. Rectangular Galaxy
“Look, up in the sky! It’s a…rectangle?” Earlier this year, astronomers spotted a celestial body, roughly 70 million light-years away, with an appearance that is unique in the visible universe: The galaxy LEDA 074886 is shaped more or less like a rectangle. While most galaxies are shaped like discs, three-dimensional ellipses or irregular blobs, this one seems to have a regular rectangle or diamond-shaped appearance. Some have speculated that the shape results from the collision of two spiral-shaped galaxies, but no one knows for now.
3. The Moon’s Magnetic Field
One of the moon’s greatest mysteries—why only some parts of the crust seem to have a magnetic field—has intrigued astronomers for decades, even inspiring the buried mythical “monolith” in the novel and film 2001: A Space Odyssey. But some scientists finally think they may have an explanation. After using a computer model to analyze the moon’s crust, researchers believe the magnetism may be a relic of a 120-mile-wide asteroid that collided with the moon’s southern pole about 4.5 billion years ago, scattering magnetic material. Others, though, believe the magnetic field may be related to other smaller, more recent impacts.
4. Why Do Pulsars Pulse?
Pulsars are distant, rapidly spinning neutron stars that emit a beam of electromagnetic radiation at regular intervals, like a rotating lighthouse beam sweeping over a shoreline. Although the first one was discovered in 1967, scientists have for decades struggled to understand what causes these stars to pulse—and, for that matter, what causes pulsars to occasionally stop pulsing. In 2008, though, when one pulsar suddenly shut off for 580 days, scientists’ observations allowed them to determine that the “on” and “off” periods are somehow related to magnetic currents slowing down the stars’ spin. Astronomers are still at work trying to understand why these magnetic currents fluctuate in the first place.
5. What Is Dark Matter?
Astrophysicists are currently trying to observe the effects of dark energy [link to Fast Forward], which accounts for some 70 percent of the universe. But it’s not the only dark stuff in the cosmos: roughly 25 percent of it is made up of an entirely separate material called dark matter. Completely invisible to telescopes and the human eye, it neither emits nor absorbs visible light (or any form of electromagnetic radiation), but its gravitational effect is evident in the motions of galaxy clusters and individual stars. Although dark matter has proven extremely difficult to study, many scientists speculate that it might be composed of subatomic particles that are fundamentally different from those that create the matter we see around us.
6. Galactic Recycling
In recent years, astronomers have noticed that galaxies form new stars at a rate that would seem to consume more matter than they actually have inside them. The Milky Way, for example, appears to turn about one sun’s worth of dust and gas into new stars every year, but it doesn’t have enough spare matter to keep this up long-term. A new study of distant galaxies might provide the answer: Astronomers noticed gas that had been expelled by the galaxies flowing back in to the center. If the galaxies recycle this gas to produce new stars, it might be a piece of the puzzle in solving the question of the missing raw matter.
7. Where Is All the Lithium?
Models of the Big Bang indicate that the element lithium should be abundant throughout the universe. The mystery, in this case, is pretty straightforward: it doesn’t. Observations of ancient stars, formed from material most similar to that produced by the Big Bang, reveal amounts of lithium two to three times lower than predicted by the theoretical models. New research indicates that some of this lithium may be mixed into the center of stars, out of view of our telescopes, while theorists suggest that axions, hypothetical subatomic particles, may have absorbed protons and reduced the amount of lithium created in the period just after the Big Bang.
8. Is There Anybody Out There?
In 1961, astrophysicist Frank Drake devised a highly controversial equation: By multiplying together a series of terms relating to the probability of extraterrestrial life (the rate of star formation in the universe, the fraction of stars with planets, the fraction of planets with conditions suitable for life, etc.) he surmised that the existence of intelligent life on other planets is extremely likely. One problem: Roswell conspiracy theorists notwithstanding, we haven’t heard from any aliens to date. Recent discoveries of distant planets that could theoretically harbor life, though, have raised hopes that we might detect extraterrestrials if we just keep looking.
9. How Will the Universe End? [Warning, Potential Spoiler Alert!]
We now believe the universe started with the Big Bang. But how will it end? Based on a number of factors, theorists conclude that the fate of the universe could take one of several wildly different forms. If the amount of dark energy is not enough to resist the compressing force of gravity, the entire universe could collapse into a singular point—a mirror image of the Big Bang, known as the Big Crunch. Recent findings, though, indicate a Big Crunch is less likely than a Big Chill, in which dark energy forces the universe into a slow, gradual expansion and all that remains are burned-out stars and dead planets, hovering at temperatures barely above absolute zero. If enough dark energy is present to overwhelm all other forces, a Big Rip scenario could occur, in which all galaxies, stars and even atoms are torn apart.
10. Across the Multiverse
Theoretical physicists speculate that our universe may not be the only one of its kind. The idea is that our universe exists within a bubble, and multiple alternative universes are contained within their own distinct bubbles. In these other universes, the physical constants—and even the laws of physics—may differ drastically. Despite the theory’s resemblance to science fiction, astronomers are now looking for physical evidence: Disc-shaped patterns in the cosmic background radiation left over from the Big Bang, which could indicate collisions with other universes.
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Top Ten Infrared Space Pictures
1. Helix Nebula. A newly expanded image of the Helix Nebula (pictured) is one of the ten infrared pictures chosen by scientists to celebrate the thousand days that the Spitzer Space Telescope has been working past its retirement date. Image courtesy J. Hora, HSCfA, W. Latter, Herschel, and Caltech/NASA
2. Mountains of Creation. An infrared photograph of the star-forming region W5, aka the Mountains of Creation (pictured), was taken before Spitzer’s coolant ran out. Image courtesy L. Allen, HSCfA, and Caltech/NASA
3. See-Through Sombrero. At visible wavelengths, the Sombrero galaxy is a fuzzy white ball encircled by a black-rimmed ring of dust. Yet in infrared (pictured), the dust glows with splendor. Image courtesy R. Kennicutt, U. Arizona, and Caltech/NASA
4. Cygnus Constellation. This close-up of the Cygnus constellation was the very first picture taken after Spitzer ran out of coolant in 2009. Image courtesy Caltech/NASA
5. Trifid Nebula. One of the more striking objects in the visible-light sky is the Trifid Nebula.Image courtesy J. Rho, SSC/Caltech/NASA
6. Ancient Galaxies. Spitzer is widely known for its see-through views of nebulae, the Milky Way, and nearby galaxies, but it was also designed to peer back in time-possible because of the time it takes light to travel from distant objects to reach Earth. Image Courtesy Spitzer Space Telescope
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New Planet Found in Our Solar System?
Odd orbits of remote objects hint at unseen world, new calculations suggest.
In the Image: Artist’s conception of a small icy object beyond Pluto (file picture).
An as yet undiscovered planet might be orbiting at the dark fringes of the solar system, according to new research.
Too far out to be easily spotted by telescopes, the potential unseen planet appears to be making its presence felt by disturbing the orbits of so-called Kuiper belt objects, said Rodney Gomes, an astronomer at the National Observatory of Brazil in Rio de Janeiro.
Kuiper belt objects are small icy bodies—including some dwarf planets—that lie beyond the orbit of Neptune.
Once considered the ninth planet in our system, the dwarf planet Pluto, for example, is one of the largest Kuiper belt objects, at about 1,400 miles (2,300 kilometers) wide. Dozens of the other objects are hundreds of miles across, and more are being discovered every year.
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Edge-on Beauty (NGC 891)
Visible in the constellation of Andromeda, NGC 891 is located approximately 30 million light-years away from Earth. The NASA/ESA Hubble Space Telescope turned its powerful wide field Advanced Camera for Surveys towards this spiral galaxy and took this close-up of its northern half. The galaxy’s central bulge is just out of the image on the bottom left.
Credit: NASA/ESA/Hubble
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Vanadinite Crystals On Baryte by Paul’s Lab on Flickr
This is a photo of a group of vanadinite crystals on baryte crystals, at 20x magnification.
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Huge Sunspot Aimed at Earth — Eruption Imminent?
The active region in question, called AR1476, is huge. In fact, as cheerfully pointed out by the SDO’s little yellow chicken mascot Camilla, the sunspot complex underlying the active region is about the size of Jupiter! In the image shown above, we are looking at light generated by plasma (heated to approximately 6,000 Celsius/Kelvin) in the sun’s photosphere. The sunspots appear dark as the sun’s intense magnetic field is thrusting through the photosphere from the interior, pushing the hotter surface layers aside, exposing the cooler plasma below.
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‘Ring of Fire’ Solar Eclipse Occurs May 20
Skywatchers in East Asia and the western United States should circle Sunday (May 20) on their calendars. That’s when a solar eclipse will block out most of the sun, leaving a spectacular “ring of fire” shining in the sky for observers located along the eclipse’s path.
The event is what’s known as an annular solar eclipse — from the Latin “annulus,” meaning “little ring” — and its full glory should be visible from much of Asia, the Pacific region and some of western North America, weather permitting. At its peak, the eclipse will block about 94 percent of the sun’s light.
CREDIT: Hinode/XRT
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Is This the Trippiest Image Ever Taken In Space? Most Probably
The image was made by Expedition 31 Flight Engineer Don Pettit, who composited it from 18 different shots:
My star trail images are made by taking a time exposure of about 10 to 15 minutes. However, with modern digital cameras, 30 seconds is about the longest exposure possible, due to electronic detector noise effectively snowing out the image. To achieve the longer exposures I do what many amateur astronomers do. I take multiple 30-second exposures, then ‘stack’ them using imaging software, thus producing the longer exposure.
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