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Showing posts with label Asteroid. Show all posts
Showing posts with label Asteroid. Show all posts

Asteroid Caught Marching Across Tadpole Nebula

Written By esperanza on Sunday, October 9, 2011 | 12:41 AM

This infrared image from NASA's Wide-field Infrared Survey Explorer, or WISE, showcases the Tadpole Nebula, a star-forming hub in the Auriga constellation about 12,000 light-years from Earth. As WISE scanned the sky, capturing this mosaic of stitched-together frames, it happened to catch an asteroid in our solar system passing by. The asteroid, called 1719 Jens, left tracks across the image. A second asteroid was also observed cruising by.


But that's not all that WISE caught in this busy image -- two natural satellites orbiting above WISE streak through the image, appearing as faint green trails. This Tadpole region is chock full of stars as young as only a million years old -- infants in stellar terms -- and masses over 10 times that of our sun. It is called the Tadpole nebula because the masses of hot, young stars are blasting out ultraviolet radiation that has etched the gas into two tadpole-shaped pillars, called Sim 129 and Sim 130. These "tadpoles" appear as the yellow squiggles near the center of the frame. The knotted regions at their heads are likely to contain new young stars. WISE's infrared vision is helping to ferret out hidden stars such as these.

The 1719 Jens asteroid, discovered in 1950, orbits in the main asteroid belt between Mars and Jupiter. The space rock, which has a diameter of 19 kilometers (12 miles), rotates every 5.9 hours and orbits the sun every 4.3 years.

Twenty-five frames of the region, taken at all four of the wavelengths detected by WISE, were combined into this one image. The space telescope caught 1719 Jens in 11 successive frames. Infrared light of 3.4 microns is color-coded blue: 4.6-micron light is cyan; 12-micron-light is green; and 22-micron light is red.

WISE is an all-sky survey, snapping pictures of the whole sky, including everything from asteroids to stars to powerful, distant galaxies.
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Asteroid Caught Marching Across Tadpole Nebula

Written By admin on Tuesday, September 27, 2011 | 3:34 PM

This infrared image from NASA's Wide-field Infrared Survey Explorer, or WISE, showcases the Tadpole Nebula, a star-forming hub in the Auriga constellation about 12,000 light-years from Earth. As WISE scanned the sky, capturing this mosaic of stitched-together frames, it happened to catch an asteroid in our solar system passing by. The asteroid, called 1719 Jens, left tracks across the image. A second asteroid was also observed cruising by.

But that's not all that WISE caught in this busy image -- two natural satellites orbiting above WISE streak through the image, appearing as faint green trails. This Tadpole region is chock full of stars as young as only a million years old -- infants in stellar terms -- and masses over 10 times that of our sun. It is called the Tadpole nebula because the masses of hot, young stars are blasting out ultraviolet radiation that has etched the gas into two tadpole-shaped pillars, called Sim 129 and Sim 130. These "tadpoles" appear as the yellow squiggles near the center of the frame. The knotted regions at their heads are likely to contain new young stars. WISE's infrared vision is helping to ferret out hidden stars such as these.

The 1719 Jens asteroid, discovered in 1950, orbits in the main asteroid belt between Mars and Jupiter. The space rock, which has a diameter of 19 kilometers (12 miles), rotates every 5.9 hours and orbits the sun every 4.3 years.

Twenty-five frames of the region, taken at all four of the wavelengths detected by WISE, were combined into this one image. The space telescope caught 1719 Jens in 11 successive frames. Infrared light of 3.4 microns is color-coded blue: 4.6-micron light is cyan; 12-micron-light is green; and 22-micron light is red.

WISE is an all-sky survey, snapping pictures of the whole sky, including everything from asteroids to stars to powerful, distant galaxies.
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The Asteroid family that produced the dinosaur-killing asteroid

Written By admin on Wednesday, September 21, 2011 | 4:11 AM

The asteroid family that produced the dinosaur-killing asteroid remains at large. Evidence that a 10-kilometer (about 6.2-mile) asteroid impacted Earth 65 million years ago includes a huge, crater-shaped structure in the Gulf of Mexico and rare minerals in the fossil record, which are common in meteorites but seldom found in Earth's crust. In addition to the Baptistina results, the NEOWISE study shows various main belt asteroid families have similar reflective properties. The team hopes to use NEOWISE data to disentangle families that overlap and trace their histories.


This calculation was possible because the size and reflectivity of the asteroid family members indicate how much time would have been required to reach their current locations -- larger asteroids would not disperse in their orbits as fast as smaller ones. The results revealed a chunk of the original Baptistina asteroid needed to hit Earth in less time than previously believed, in just about 15 million years, to cause the extinction of the dinosaurs.

The NEOWISE team measured the reflectivity and the size of about 120,000 asteroids in the main belt, including 1,056 members of the Baptistina family. The scientists calculated the original parent Baptistina asteroid actually broke up closer to 80 million years ago.

"This doesn't give the remnants from the collision very much time to move into a resonance spot, and get flung down to Earth 65 million years ago," said Amy Mainzer, a co-author of a new study appearing in the Astrophysical Journal and the principal investigator of NEOWISE at NASA's Jet Propulsion Laboratory (JPL) in Pasadena. Calif. "This process is thought to normally take many tens of millions of years." Resonances are areas in the main belt where gravity nudges from Jupiter and Saturn can act like a pinball machine to fling asteroids out of the main belt and into the region near Earth.

Visible light reflects off an asteroid. Without knowing how reflective the surface of the asteroid is, it's hard to accurately establish size. Infrared observations allow a more accurate size estimate. They detect infrared light coming from the asteroid itself, which is related to the body's temperature and size. Once the size is known, the object's reflectivity can be re-calculated by combining infrared with visible-light data.

JPL manages and operated WISE for NASA's Science Mission Directorate. The spacecraft was put into hibernation mode after it scanned the entire sky twice, completing its main objectives. The principal investigator, astronomer Edward Wright, is at UCLA. The mission was selected compe

titively under NASA's Explorers Program managed by the agency's Goddard Space Flight Center in Greenbelt, Md. The science instrument was built by the Space Dynamics Laboratory in Logan. The spacecraft was built by Ball Aerospace & Technologies Corp. in Boulder, Colo. Science operations and data processing take place at the Infrared Processing and Analysis Center at the California Institute of Technology in Pasadena. Caltech manages JPL for NASA.
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Origin of Dinosaur - Earth's greatest mysteries 1

Written By admin on Tuesday, September 20, 2011 | 4:39 AM

Open the case on one of Earth's greatest mysteries Searching for the Origins of the Dinosaur-Killing Asteroid

Scientists think that a giant asteroid, which broke up long ago in the main asteroid belt between Mars and Jupiter, eventually made its way to Earth and led to the extinction of the dinosaurs. Data from NASA's WISE mission likely rules out the leading suspect, a member of a family of asteroids called Baptistina, so the search for the origins of the dinosaur-killing asteroid goes on. 


According to that theory, Baptistina crashed into another asteroid in the main belt between Mars and Jupiter about 160 million years ago. The collision sent shattered pieces as big as mountains flying. One of those pieces was believed to have impacted Earth, causing the dinosaurs' extinction.

While scientists are confident a large asteroid crashed into Earth approximately 65 million years ago, leading to the extinction of dinosaurs and some other life forms on our planet, they do not know exactly where the asteroid came from or how it made its way to Earth. A 2007 study using visible-light data from ground-based telescopes first suggested the remnant of a huge asteroid, known as Baptistina, as a possible suspect.

Since this scenario was first proposed, evidence developed that the so-called Baptistina family of asteroids was not the responsible party. With the new infrared observations from WISE, astronomers say Baptistina may finally be ruled out.

"As a result of the WISE science team's investigation, the demise of the dinosaurs remains in the cold case files," said Lindley Johnson, program executive for the Near Earth Object (NEO) Observation Program at NASA Headquarters in Washington. "The original calculations with visible light estimated the size and reflectivity of the Baptistina family members, leading to estimates of their age, but we now know those estimates were off. With infrared light, WISE was able to get a more accurate estimate, which throws the timing of the Baptistina theory into question."

WISE surveyed the entire celestial sky twice in infrared light from January 2010 to February 2011. The asteroid-hunting portion of the mission, called NEOWISE, used the data to catalogue more than 157,000 asteroids in the main belt and discovered more than 33,000 new ones.

How is the Truth story of the Dinosaur Extinction........?
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Tiny Asteroid Approaches Earth

Written By admin on Saturday, September 17, 2011 | 4:41 AM

Using the Marshall Space Flight Center 0.5 meter telescope in New Mexico, NASA astronomer Rob Suggs captured this view of the tiny asteroid 2010 TG19 as it made its way among the stars of the constellation Pegasus.



Taken before sunup on Oct. 15, the animated sequence shows the movement of the asteroid, then 4.25 million miles away from Earth, over 45 minutes. Only 75 yards across, 2010 TG19 is very faint at magnitude +18 , which is near the limit of the telescope. It will continue to approach during the next few days, finally coming within 268,500 miles of our planet, or almost as close as the moon, at noon EDT on Friday, Oct. 22.
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A Planet as Big as Its Star

Written By Admin on Friday, January 28, 2011 | 4:36 PM

This artist's concept shows the smallest star known to host a planet. The planet, called VB 10b, was discovered using astrometry, a method in which the wobble induced by a planet on its star is measured precisely on the sky.

big_planet

The dim, red star, called VB 10, is a so-called M-dwarf, located 20 light-years away in the constellation Aquila. It has only one-twelfth the mass, and one-tenth the size, of our sun. The planet is a gas giant similar in size to Jupiter but with six times the mass. Though the planet is less massive than its star, the two orbs would have a similar diameter.

VB 10b orbits its star about every 9 months at a distance of 50 million kilometers (30 million miles).

Read more......
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Asteroids Could Have Made Life's Ingredients

Written By Admin on Wednesday, January 19, 2011 | 12:03 AM

A wider range of asteroids were capable of creating the kind of amino acids used by life on Earth, according to new NASA research.

Amino acids are used to build proteins, which are used by life to make structures like hair and nails, and to speed up or regulate chemical reactions. Amino acids come in two varieties that are mirror images of each other, like your hands. Life on Earth uses the left-handed kind exclusively. Since life based on right-handed amino acids would presumably work fine, scientists are trying to find out why Earth-based life favored left-handed amino acids.

In March, 2009, researchers at NASA's Goddard Space Flight Center in Greenbelt, Md., reported the discovery of an excess of the left-handed form of the amino acid isovaline in samples of meteorites that came from carbon-rich asteroids. This suggests that perhaps left-handed life got its start in space, where conditions in asteroids favored the creation of left-handed amino acids. Meteorite impacts could have supplied this material, enriched in left-handed molecules, to Earth. The bias toward left-handedness would have been perpetuated as this material was incorporated into emerging life.

In the new research, the team reports finding excess left-handed isovaline (L-isovaline) in a much wider variety of carbon-rich meteorites. "This tells us our initial discovery wasn't a fluke; that there really was something going on in the asteroids where these meteorites came from that favors the creation of left-handed amino acids," says Dr. Daniel Glavin of NASA Goddard. Glavin is lead author of a paper about this research published online in Meteoritics and Planetary Science January 17.

"This research builds on over a decade of work on excesses of left-handed isovaline in carbon-rich meteorites," said Dr. Jason Dworkin of NASA Goddard, a co-author on the paper.

"Initially, John Cronin and Sandra Pizzarello of Arizona State University showed a small but significant excess of L-isovaline in two CM2 meteorites. Last year we showed that L-isovaline excesses appear to track with the history of hot water on the asteroid from which the meteorites came. In this work we have studied some exceptionally rare meteorites which witnessed large amounts of water on the asteroid. We were gratified that the meteorites in this study corroborate our hypothesis," explained Dworkin.
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