New telescope sees dim objects

2009-11-18 19:37

Los Angeles - Nasa plans next month to launch a space telescope that will scan the heavens for the infrared glow of celestial objects never seen because they are too dim, dusty or distant, scientists said on Tuesday.

The Wide-field Infrared Survey Explorer, or Wise, is expected to reveal hundreds of thousands of dark asteroids lurking undetected in the solar system, and millions of elusive stars and galaxies farther out in space.

The spacecraft, to be carried into orbit by a Delta 2 rocket, will roll out to its launch pad at Vandenberg Air Force Base in California on Friday for a lift-off slated for as early as December 9, managers of the $320m project said at a news briefing in Washington DC.

Its six-month mission is to survey the entire sky for infrared radiation, a form of light invisible to the human eye but emitted from the coldest of objects, including those overlooked by telescopes sensitive only to visible light.

"We expect certainly to see many asteroids, stars and galaxies," said Edward Wright of the University of California, Los Angeles, the mission's principal investigator. "But really I'll be surprised if I'm not surprised ... because we're going to find things that nobody has imagined yet."

The telescope sits in a tank filled with frozen hydrogen that chills it to just slightly above absolute zero, the coldest temperature theoretically attainable, thus preventing the instrument from picking up its own infrared heat.

Brown dwarfs

Among the phenomena Wise is likely to uncover is a large number of failed stars called brown dwarfs - balls of gas many times smaller than the sun that lack sufficient mass to trigger their own internal stellar engines. Optically invisible, they glow in the infrared spectrum.

Brown dwarfs are believed to be more numerous than actual stars in the nearby universe, and some may reside even closer to Earth than the nearest known star, Proxima Centauri, about 4 light years away, said Peter Eisenhardt, chief project scientist at Nasa's Jet Propulsion Laboratory. Both theories are likely to be confirmed by Wise.

Infrared light also penetrates dust, enabling Wise to both illuminate and peer through the dense, invisible haze that obscures some of the most distant galaxies in the cosmos.

A class of such objects called ultra-luminous galaxies, thought to be super-incubators of new stars, shine with more than a trillion times the light of the sun. But most of that light is emitted as infrared, Eisenhardt said.

"So we're going to find the most super-duper, hyper ultra-luminous galaxies in the universe and find just how extreme these galaxy-forming processes can get," he said.

Scientists say the spacecraft's detectors are about 500 times more sensitive than those of the last infrared sky survey in 1983, a joint European-Nasa mission.

Closer to home, Wise will likely add several hundred hidden asteroids and comets to the known inventory of "near-Earth objects" whose orbits come perilously close to Earth's orbit, while telling scientists more about their composition.

Read more on:    nasa  |  astronomy  |  technology  |  space

linking and moving

2015-04-22 07:36


Read News24’s Comments Policy

Inside News24

/South Africa

Middle-seat kids: Why are they special?

Limited legroom, a siblings on each side... the middle seat has long been considered the short straw in a car but does it have a secret?


Stay safe

Middle-seat kids: Why are they special?
Juvenile pillion riders? Play safe...
First-aid kit: What you need in YOUR car
Hey, lazy! Get outta the disabled bay!

You may find yourself in the role of team leader whether you like it or not. You are good at overseeing things and knowing more

There are new stories on the homepage. Click here to see them.


Create Profile

Creating your profile will enable you to submit photos and stories to get published on News24.

Please provide a username for your profile page:

This username must be unique, cannot be edited and will be used in the URL to your profile page across the entire network.


Location Settings

News24 allows you to edit the display of certain components based on a location. If you wish to personalise the page based on your preferences, please select a location for each component and click "Submit" in order for the changes to take affect.

Facebook Sign-In

Hi News addict,

Join the News24 Community to be involved in breaking the news.

Log in with Facebook to comment and personalise news, weather and listings.