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Recently Reactivated NASA Spacecraft Spots Its First New Asteroid
NASA’s Near-Earth Object Wide-field Infrared Survey Explorer (NEOWISE) spacecraft has spotted a never-before-seen asteroid — its first such discovery since coming out of hibernation last year.
NEOWISE originally was called the Wide-field Infrared Survey Explorer (WISE), which had made the most comprehensive survey to date of asteroids and comets. The spacecraft was shut down in 2011 after its primary mission was completed. But in September 2013, it was reactivated, renamed and given a new mission, which is to assist NASA’s efforts to identify the population of potentially hazardous near-Earth objects (NEOs). NEOWISE also can assist in characterizing previously detected asteroids that could be considered potential targets for future exploration missions
NEOWISE’s first discovery of its renewed mission came on Dec. 29 — a near-Earth asteroid designated 2013 YP139. The mission’s sophisticated software picked out the moving object against a background of stationary stars. As NEOWISE circled Earth scanning the sky, it observed the asteroid several times over half a day before the object moved beyond its view. Researchers at the University of Arizona used the Spacewatch telescope at the Kitt Peak National Observatory southwest of Tucson to confirm the discovery. Peter Birtwhistle, an amateur astronomer at the Great Shefford Observatory in West Berkshire, England, also contributed follow-up observations. NASA expects 2013 YP139 will be the first of hundreds of asteroid discoveries for NEOWISE.
UH Observations Result In “All Clear” For Potential Asteroid Impact
Using the Gemini North telescope on Mauna Kea, Hawai‘i a team of astronomers from the University of Hawaii’s Institute for Astronomy (IfA) have confirmed that the chance of asteroid 2011 AG5 impacting Earth in 2040 is no longer a significant risk – prompting a collective sigh-of-relief. Previously, scientists estimated that the risk of this 140-meter-diameter (about the length of two American football fields) asteroid colliding with the Earth was as high as one in 500.
If this object were to collide with the Earth it would have released about 100 megatons of energy, several thousand times more powerful than the atomic bombs that ended World-War II. Statistically, a body of this size could impact the Earth on average every 10,000 years.
Full Story: http://www.gemini.edu/node/11922
Also: http://www.ifa.hawaii.edu/info/press-releases/allclear2011AG5.shtml
New Report: Hazardous Near Eearth Objects – Communicating The Risk
To deal with potentially hazardous Near Earth Objects (NEOs) that could strike the Earth, there is need to establish an effective international communications strategy – but doing so is a daunting task, one that demands effective use of mass communication tools.
The report and its findings are being presented this week to the United Nations Committee on the Peaceful Uses of Outer Space (COPUOS) and its Action Team-14 on NEOs during the 55th session of the UN COPUOS being held in Vienna, Austria.
Full Story: http://www.newswise.com/articles/view/589977/?sc=dwtr&xy=5028369
Earth Usually Has More Than One Moon
Earth usually has more than one moon, according to a team of astronomers from the University of Helsinki, the Paris Observatory and the University of Hawaii at Manoa.
Our 2,000-mile-diameter Moon, so beloved by poets, artists and romantics, has been orbiting Earth for over 4 billion years. Its much smaller cousins, dubbed “minimoons,” are thought to be only a few feet across and to usually orbit our planet for less than a year before resuming their previous lives as asteroids orbiting the Sun.
Mikael Granvik (formerly at UH Manoa and now at Helsinki), Jeremie Vaubaillon (Paris Observatory) and Robert Jedicke (UH Manoa) calculated the probability that at any given time Earth has more than one moon. They used a supercomputer to simulate the passage of 10 million asteroids past Earth. They then tracked the trajectories of the 18,000 objects that were captured by Earth’s gravity.
They concluded that at any given time there should be at least one asteroid with a diameter of at least one meter orbiting Earth. Of course, there may also be many smaller objects orbiting Earth, too.
Full Story: http://www.ifa.hawaii.edu/info/press-releases/minimoons/
New X2 Solar Flare & Asteroid Flyby
Asteroid Flyby
Newly-discovered asteroid 2012 BX34 is flying past Earth today only 77,000 km (0.2 lunar distances) away. There is no danger of a collision with the 14-meter wide space rock.
X2 Solar Flare
Departing sunspot 1402 unleashed an X2-class solar flare today, Jan. 27th, at 18:37 UT. Sunspot 1402 is rotating onto the far side of the sun, so the blast site was not facing Earth. Nevertheless, energetic protons accelerated by the blast are now surrounding our planet, and an intensifying S1-class radiation storm is in progress.
Full Stories: http://spaceweather.com/archive.php?month=01&day=27&year=2012&view=view
Student’s Work Helps to Detect Near Earth Asteroids
An asteroid impact with the earth can really ruin your day: just consider the dinosaurs. Most asteroids, also known as minor planets, orbit the sun beyond the planet Mars and present no danger, but there is a class of asteroids whose orbits cross the orbit of the earth. If one of these asteroids and the earth are at the same point in their orbits at the same time, a collision could occur. Called Near Earth Objects (NEOs), astronomers are interested in discovering as many of these as possible, and then tracking them in order to compute more accurate orbits. In this way, if a potential future collision were to be identified many years in advance, space probes could carry out steps to tweak the path of the NEO and deflect the collision. A program to track NEOs is being carried out at NOAO by Mark Trueblood with Robert Crawford (Rincon Ranch Observatory) and Larry Lebofsky (Planetary Science Institute). And last summer, a Beloit College student, Morgan Rehnberg, has developed a computer program (PhAst), available via the web, to help with this effort.
Asteroids move quickly across the sky, so in order to recover and track them, fast and accurate data reduction and analysis is essential. Unlike most of the data that astronomers work with, tracking a fast moving asteroid requires that the observer view multiple digital images obtained at the telescope by blinking between them, almost like a movie. In addition, accurate coordinates locating the NEO in the sky need to be computed. (Termed right ascension and declination, these are similar in concept to the latitude and longitude of a position on earth.) While there are many software packages that amateur and professional astronomers use (Maxim DL, Astrometrica) none did exactly what the group required. Seeing the need for better software but not having the time to devote to the task of writing it, Trueblood saw this as an ideal project for a summer student.
Full Story: http://www.noao.edu/news/2011/pr1107.php
Updated Radar Movie of Asteroid 2005 YU55
NASA Scientists working with the 230-foot-wide (70-meter) Deep Space Network antenna at Goldstone, Calif., have released a second, longer, and more refined, movie clip of asteroid 2005 YU55. The images were generated from data collected at Goldstone on Nov. 7, 2011, between 11:24 a.m. and 1:35 p.m. PST (2:24 p.m. and 4:35 p.m. EST).
The movie clip can be found at: http://1.usa.gov/YU55 .
Each of the 28 frames required 20 minutes of data collection by the Goldstone radar. At the time of the observations, 2005 YU55 was approximately 860,000 miles (1.4 million kilometers) from Earth. The resolution is about 13 feet (4 meters) per pixel. 2005 YU55 takes approximately 18 hours to complete one rotation, so the rotation in the movie appears much more rapid than the actual asteroid rotation speed.
The Goldstone observations utilized a new system to obtain images with a resolution of 4 meters, which is five times finer than the highest resolution previously possible at Goldstone.
Full Story: http://www.jpl.nasa.gov/news/news.cfm?release=2011-351
NASA’s Swift Observatory Catches Asteroid Flyby
As asteroid 2005 YU55 swept past Earth in the early morning hours of Wednesday, Nov. 9, telescopes aboard NASA’s Swift satellite joined professional and amateur astronomers around the globe in monitoring the fast-moving space rock. The unique ultraviolet data will aid scientists in understanding the asteroid’s surface composition.
“Swift’s ultraviolet and X-ray capability gives scientists a unique perspective on comets and asteroids, expanding the spectral window beyond the radio, infrared and optical observations so well handled by big ground-based facilities,” said Sergio Campana, a Swift team member at Brera Observatory in Merate, Italy. Campana requested that the spacecraft train its telescopes on the asteroid as a target of opportunity.
Although Swift is better known for its study of high-energy outbursts and cosmic explosions, the versatile satellite has made valuable observations of passing comets and asteroids as well. All told, the spacecraft has observed ten asteroids, including Vesta — now being studied close-up by NASA’s Dawn spacecraft — and Scheila, which brightened unexpectedly in late 2010 after colliding with a much smaller asteroid.
Full Story: http://www.nasa.gov/mission_pages/swift/bursts/asteroid-yu55.html
NASA Releases Radar Movie of Asteroid 2005 YU55
Scientists working with the 230-foot-wide (70-meter) Deep Space Network antenna at Goldstone, Calif., have generated a short movie clip of asteroid 2005 YU55. The images were generated from data collected at Goldstone on Nov. 7, 2011, between 11:24 a.m. and 1:35 p.m. PST (2:24 p.m. and 4:35 p.m. EST). They are the highest-resolution images ever generated by radar of a near-Earth object.
The short movie clip can be found at: http://1.usa.gov/uVJvmS .
Each of the six frames required 20 minutes of data collection by the Goldstone radar. At the time, 2005 YU55 was approximately 860,000 miles (1.38 million kilometers) away from Earth. Resolution is 4 meters per pixel.
“The movie shows the small subset of images obtained at Goldstone on November 7 that have finished processing. By animating a sequence of radar images, we can see more surface detail than is visible otherwise,” said radar astronomer Lance Benner, the principal investigator for the 2005 YU55 observations, from NASA’s Jet Propulsion Laboratory in Pasadena, Calif. “The animation reveals a number of puzzling structures on the surface that we don’t yet understand. To date, we’ve seen less than one half of the surface, so we expect more surprises.”
Full Story: http://www.jpl.nasa.gov/news/news.cfm?release=2011-346
Watch Mini-Asteroid 2005 YU55 Buzz Earth
Earth is about to be visited by the largest close-approaching asteroid on record. Known as 2005 YU55, it is about a quarter mile (400 m) across, round, and quite dark. When it comes closest to us, at 6:28 p.m. EST (23:28 Universal Time) on November 8th, it will be 198,000 miles (319,000 km) from Earth’s surface — closer than the Moon’s orbit. Professional astronomers around the world will closely follow the asteroid as it glides across the sky.
Weather permitting, backyard skywatchers also have a chance to spot this interloper. A few hours after passing closest to us, it will peak in brightness at magnitude 11.1, roughly 100 times fainter than the limit of human vision. “The good news,” says Alan MacRobert of Sky & Telescopemagazine, “is that you should be able to spot the asteroid with your telescope if it has an aperture of at least 6 to 8 inches.”
Full Story: http://www.skyandtelescope.com/about/pressreleases/133357483.html
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