NASA-International Space Station

NASA's Wide-field Infrared Survey Explorer, or WISE, has exposed its first comet, one of many the mission is expected to find among millions of other objects during its ongoing survey of the whole sky in infrared light.

Officially named "P/2010 B2 (WISE)," but known merely as WISE, the comet is a dusty mass of ice more than 2 kilometers (1.2 miles) in diameter. It probably formed around the same time as our solar system, about 4.5 billion years ago. Comet WISE started out in the cold, dark reaches of our solar system, but after a long history of getting knocked around by the gravitational forces of Jupiter, it settled into an orbit much quicker to the sun. Right now, the comet is heading away from the sun and is about 175 million kilometers (109 million miles) from Earth.

"Comets are ancient reservoirs of water. They are one of the few places in addition Earth in the inner solar system where water is known to exist," said Amy Mainzer of NASA's Jet Propulsion Laboratory in Pasadena, Calif. Mainzer is the principal investigator of NEOWISE, a project to find and catalog new asteroids and comets spotted by WISE (the acronym combines WISE with NEO, the shorthand for near-Earth object).

"With WISE, we have a powerful tool to find new comets and learn more about the population as a whole. Water is necessary for life as we know it, and comets can tell us more about how much there is in our solar system."

The WISE telescope, which launched into a polar orbit around Earth on Dec. 14, 2009, is expected to discover anywhere from a few to dozens of new comets, in addition to hundreds of thousands of asteroids. Comets are harder to find than asteroids because they are much more rare in the inner solar system. Whereas asteroids tour around in the "main belt" between the orbits of Mars and Jupiter, large numbers of comets orbit farther away, in the icy outer reaches of our solar system.

Both asteroids and comets can fall into orbits that bring them close to Earth's path around the sun. Most of these "near-Earth objects" are asteroids but some are comets. WISE is expected to find new near-Earth comets, and this will give us a better idea of how threatening they might be to Earth.

"It is very unlikely that a comet will hit Earth," said James Bauer, a scientist at JPL working on the WISE project, "But, in the rare chance that one did, it could be dangerous. The new discoveries from WISE will give us more precise statistics about the probability of such an event, and how powerful an impact it might yield."

The space telescope spotted the comet during its routine scan of the sky on January 22. Sophisticated software plucked the comet out from the stream of images pouring down from space by looking for objects that move quickly relative to background stars. The comet discovery was followed up by a combination of professional and amateur astronomers using telescopes across the United States.

A teacher also teamed up with an observer to measure comet WISE using a home-built telescope next to a cornfield in Illinois. Their research is part of the International Astronomical Search Collaboration, an education program that helps teachers and students observe comets and asteroids (more information is online at http://iasc.hsutx.edu/).

All the data are catalogued at the Minor Planet Center, in Cambridge, Mass., the worldwide clearinghouse for all observations and orbits of minor planets and comets.

Comet WISE takes 4.7 years to circle the sun, with its farthest point being about 4 astronomical units away, and its closest point being 1.6 astronomical units (near the orbit of Mars). An astronomical unit is the distance between Earth and the sun. Heat from the sun causes gas and dust to blow off the comet, resulting in a dusty coma, or shell, and a tail.

Though this particular body is actively shedding dust, WISE is also expected to find dark, dead comets. Once a comet has taken many trips around the sun, its icy components erode away, leaving only a dark, rocky core. Not much is known about these objects because they are hard to see in visible light. WISE's infrared sight should be able to pick up the feeble glow of some of these dark comets, answering questions about precisely how and where they form.

"Dead comets can be darker than coal," said Mainzer. "But in infrared light, they will pop into view. One question we want to answer with WISE is how many dead comets make up the near-Earth object population."

The mission will spend the next eight months mapping the sky one-and-a-half times. A first batch of data will be available to the public in the spring of 2011, and the final catalog a year later. Selected images and findings will be released throughout the mission.

JPL manages the Wide-field Infrared Survey Explorer for NASA's Science Mission Directorate, Washington. The principal investigator, Edward Wright, is at UCLA. The mission was competitively selected under NASA's Explorers Program managed by the Goddard Space Flight Center, Greenbelt, Md. The science instrument was built by the Space Dynamics Laboratory, Logan, Utah, and the spacecraft was built by Ball Aerospace & Technologies Corp., 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. The ground-based observations are partly supported by the National Science Foundation. The Minor Planet Center is funded by NASA. More information is online at http://www.nasa.gov/wise and http://wise.astro.ucla.edu.

This infrared photograph of a region in the constellation Carina near the Milky Way was taken shortly after NASA's Wide-field Infrared Survey Explorer (WISE) expelled its cover. The "first-light" image shows thousands of stars and covers an area three times the size of the moon. WISE will take more than a million alike pictures covering the whole sky.

The image was captured as the spacecraft stared in a fixed direction, in order to help standardize its pointing system. The mission's analysis will be done while the satellite continuously scans the sky, and an internal scan mirror counteracts the motion to create freeze-frame images. The team is working now to match the motions of the spacecraft and the scan mirror accurately.

This eight-second revelation 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.

More information is online at http://www.nasa.gov/wise and http://wise.astro.ucla.edu/.

NASA's Wide-field Infrared Survey Explorer, or WISE, lifted off over the Pacific Ocean 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. The rocket deposited WISE 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 excellent, and we are on our way to considering the whole infrared sky improved than ever before."

Engineers acquired a indication from the spacecraft via NASA's Tracking and Data Relay Satellite System just 10 seconds after the spacecraft separated from the rocket. Approximately three minutes later, WISE re-oriented itself with its solar panels facing the sun to produce its own power. The next major event occurred about 17 minutes later. Valves on the cryostat, a chamber of super-cold hydrogen ice that cools the WISE instrument, opened. 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 substance’s 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 in progress. 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 major mission will end when WISE's frozen hydrogen runs out, about 10 months after launch.

After two delays, NASA is planned to launch an unmanned orbiting observatory that promises to greatly enhance, and considerably change, humanity's understanding of the heavens.

The Wide-field Infrared Survey Explorer (WISE) is likely to launch from Vandenberg Air Force Base near Santa Barbara, Calif., between 9:09 and 9:23 a.m. Eastern time. From its eventual orbit 325 miles above earth, it will start a blitz of picture-taking with equipment of unprecedented sensitivity. WISE will map the heavens on four infrared channels, frequencies of long-wave radiation that are unseen to the human eye and many telescopes.

Mission managers have implemented a plan to totally resolve the anomaly. This plan includes removing and replacing a suspect component on Friday, Dec. 11, allowing the Delta II to be prepared for Monday’s launch attempt. The current weather forecast calls for an 80 percent chance of suitable weather during the launch window.

WISE will circle Earth over the poles, scanning the entire sky one-and-a-half times in nine months. The mission will discover hidden cosmic objects, including the coolest stars, dark asteroids and the most luminous galaxies.

Edward Wright, the chief investigator for the mission at the University of California, said: "We will find millions of objects that have never been seen before."

Further afield, it could identify galaxies that are shrouded by dust, or so ancient and remote that current telescopes cannot make them out.

Excitingly, it may also find a theoretical ninth planet in our own solar system (since Pluto is no longer counted as a planet, there are at present only eight).

The patterns of comet orbits around our sun suggests that there may be a enormous gas giant planet, about 25,000 times as far from the Sun as the Earth is, as yet undetected.

The Wise telescope may possibly spot a Jupiter-sized planet as far as 60,000 Earth-to-Sun-distances (called astronomical units, or Aus) from the Sun, according to one of the scientists behind it, Peter Eisenhardt of NASA's Jet Propulsion Laboratory in Pasadena, California, and it will be vigorously looking for the distant giant.

It is believable, if unlikely, that the telescope could save the planet, as well. Since it will be able to spot formerly invisible asteroids, it might give us enough warning to do something about it if one was on a collision course with Earth.