WISE Bags its First Near-Earth Asteroid

The red dot at the center of this image is the first near-Earth asteroid discovered by NASA's Wide-Field Infrared Survey Explorer, or WISE Image credit: NASA/JPL-Caltech/UCLA


Well, that didn’t take long: The WISE spacecraft (Wide-field Infrared Survey Explorer) spotted its first near-Earth asteroid on January 12, 2010, two days before the official start of its all-sky survey. That’s a pretty good catch, considering WISE just popped it lens cover a couple of weeks ago (December 29, 2009) and released its “first light” image on January 6. This is the first of what researchers hope will be thousands of previously undiscovered asteroids in the main asteroid belt, and hundreds of new near-Earth asteroids. By mapping the whole sky in infrared light, it should also be able to capture millions of new stars and galaxies.

WISE’s software picked up the object, 2010 AB78, moving against a background of stationary stars. Researchers followed up and confirmed the discovery with the University of Hawaii’s 2.2-meter (88-inch) visible-light telescope near the summit of Mauna Kea.

This asteroid does not pose any foreseeable impact threat to Earth, but scientists will continue to monitor it. 2010 AB78 is currently about 158 million kilometers (98 million miles) from Earth. It is estimated to be roughly 1 kilometer (0.6 miles) in diameter and circles the sun in an elliptical orbit tilted to the plane of our solar system. The object comes as close to the sun as Earth, but because of its tilted orbit, it is not thought to pass near our planet.

Source: JPL

WISE “First Light” Image Released

WISE First Light image. Image credit: NASA/JPL-Caltech/UCLA

Caption: WISE First Light image. Image credit: NASA/JPL-Caltech/UCLA

“In many respects, the most important moment for a telescope is its first light,” said Bill Irace, project manager for the Wide-field Infrared Survey Explorer (WISE) spacecraft, speaking at the 215th American Astronomical Society meeting. “And we are happy to be able to share WISE’s first light image with you today.” The image covers a patch of sky about three times larger than the full moon. An interstellar dust cloud shows in the upper left, and the bright object in the right-center is V 482 Carina, an old puffy, cool giant star. The image was taken with what will be WISE’s standard 8.8 seconds of exposure time where it “stares” at a specific point in the sky. Ultimately, WISE will take millions of images to conduct an all sky survey in 10 months, before the frozen hydrogen that keeps the instrument cold evaporates away.

The exposure shows infrared light from three of WISE’s four wavelength bands: Blue, green and red correspond to 3.4, 4.6, and 12 microns, respectively. WISE will search for millions of hidden objects, including asteroids, “failed” stars, powerful galaxies and brown dwarf stars too cool to emit light, including a potential brown dwarf that might be closer to Earth than Proxima Centauri. WISE data will also serve as navigation charts for other missions.

Irace and David Leisawitz from Goddard Space Flight Center said in about a month, the science team will release the first images from the first survey to the public. “Longer term, the astronomical community around the world has been looking forward to this,” said Leisawitz, “as all of WISE’s data will be released for anyone to use starting in April 2011, with the final release in March 2012. The data products include an atlas of images and catalog of individual objects.”

Leisawitz said that magnificently and stunningly, WISE provides 400 times better angular resolution than the infrared instrument on the COBE spacecraft.

Irace divulged that this image was strictly an engineering image with no regard to the field of view. “We actually took about six images, but this one was the prettiest,” he said. “We did not point at a particular point in the sky, and in fact we didn’t know if we were going to be able to do it this fast, so this is basically a random image.”

The science team believes the spacecraft will still be operational for 3 additional months following the 10 month prime mission, and are writing a proposal to NASA for funding to continue.

For a larger version of the image, visit this NASA webpage.

Source: AAS press conference

WISE Launches to Begin All-Sky Survey (Video)

WISE launch. Image Credit: Bill Hartenstein/United Launch Alliance

NASA’s Wide-field Infrared Survey Explorer, or WISE, successfully lifted off this morning on its way to map the entire sky in infrared light. A Delta II rocket carrying the spacecraft launched at 6:09 a.m. PST (9:09 a.m. EST) from Vandenberg Air Force Base in California. WISE quickly began transmitting data – just 10 seconds after spacecraft separation — and all through the events that lead to bringing the satellite into a polar orbit 326 miles above Earth.


“WISE thundered overhead, lighting up the pre-dawn skies,” said William Irace, the mission’s project manager at NASA’s Jet Propulsion Laboratory in Pasadena, Calif. “All systems are looking good, and we are on our way to seeing the entire infrared sky better than ever before.”

Because the instrument sees the infrared, or heat, signatures of objects, it must be kept at chilly temperatures. Its coldest detectors are less than minus 447 degrees Fahrenheit.

“WISE needs to be colder than the objects it’s observing,” said Ned Wright of UCLA, the mission’s principal investigator. “Now we’re ready to see the infrared glow from hundreds of thousands of asteroids, and hundreds of millions of stars and galaxies.”

With the spacecraft stable, cold and communicating with mission controllers at JPL, a month-long checkout and calibration is underway.

WISE will see the infrared colors of the whole sky with sensitivity and resolution far better than the last infrared sky survey, performed 26 years ago. The space telescope will spend nine months scanning the sky once, then one-half the sky a second time. The primary mission will end when WISE’s frozen hydrogen runs out, about 10 months after launch.

WISE will catalog a variety of astronomical targets. Near-Earth asteroids, stars, planet-forming disks and distant galaxies all will be easy for the mission to see. Hundreds of millions of objects will populate the WISE atlas, providing astronomers and other space missions, such as NASA’s planned James Webb Space Telescope, with a long-lasting infrared roadmap.

Source: NASA

NASA to Launch WISE on Friday

An artist's rendering of the WISE satellite, which will survey the sky in the infrared. Image Credit: NASA/JPL

NASA is getting WISE to the Universe this Friday. That is, they’re launching the Wide-field Infrared Survey Explorer, a new infrared space telescope that will survey objects in our Solar System and beyond, looking for asteroids and brown dwarfs close to home, and protoplanetary disks and newborn stars far off.

The WISE mission is another in a series of all-sky surveys that have become so very effective for research. The satellite will spend six months mapping the entire sky in the infrared, after which it will make a second, three-month pass to further refine the mapping. Rather than looking at any specific objects, the satellite will survey everything it can see with its infrared eyes, providing a detailed catalog of infrared-emitting objects for followup with telescopes like the Spitzer Space Telescope, the Herschel Space Observatory and the upcoming James Webb Space Telescope.

Infrared instruments detect heat, so the instrument must be cooled to a chilly 17 Kelvin (-265 degrees Celsius/ -445 degrees Fahrenheit). Otherwise, it would detect its own heat signature. This is accomplished by packing it in a cryostat, which is basically a large thermos filled with solid hydrogen. The cryostat is expected to keep the instrument cool enough for about 10 months of observation after the launch.

WISE is all ready to go, with the chilled instrument stowed safely in the nosecone that will fit atop a Delta II rocket. WISE will launch from Vandenberg Air Force Base in California on Friday, Dec. 11, between 9:09 a.m. and 9:23 a.m. EST. NASA will have live coverage of the launch available on NASA TV.

WISE tucked safely in its nose cone, ready for launch aboard a Delta II rocket this Friday. Image Credit:United Launch Alliance/ JPL-Caltech

Objects that the WISE telescope will pick up include asteroids in our own Solar System that remain undetected because they are invisible in visible light. By doing an all-sky survey, WISE is expected to see hundreds of thousands of asteroids in our Solar System that haven’t been discovered, hundreds of them lying in the path of the Earth’s orbit. By cataloging these Earth orbit-crossing objects, astronomers can get a better idea of what threats from asteroid impact are lurking in the dark.

WISE will also be sensitive enough to pick up brown dwarfs, objects that straddle the line between planet and star. Though they are massive, they don’t quite make the cut for igniting nuclear fusion in their cores, but are warm enough to emit infrared light. It’s thought that there are quite a few of these objects in our own back yard waiting to be discovered, and WISE may double or triple the amount of star-like objects that are within 25 light-years of the Earth.

In addition to these smaller, closer finds, WISE will be able to see ultra-luminous infrared galaxies out in the distant regions of the Universe. These galaxies are bright in the infrared, but are invisible to telescopes that can only see in the visible light spectrum. The catalog may be a boon to extrasolar planet hunters, as the protoplanetary disks from which these planets form will be another object visible to the instrument.

The WISE telescope will have polar orbit with an altitude of 525 km (326 miles), and will circle the Earth 15 times each day. Snapshots of the sky will be taken every eleven seconds, allowing the instrument to image each position on the sky in the telescope’s field of view a minimum of eight times.

Be sure to check back with us for further coverage of the WISE launch on Friday!

Source: NASA press release, WISE mission site