First data released from massive sky survey

An arrow points to the most distant object ever observed

By Janis Winogradsky
CNN

PASADENA, California (CNN) -- Parents whose children ask how many stars are in the sky may soon be able to give a fairly accurate response, thanks to the Sloan Digital Sky Survey, which Tuesday released early data from the most ambitious astronomical survey ever undertaken.

The survey is mapping one-quarter of the sky, determining the positions and brightness of more than 100 million celestial objects. It is estimated that only about 3,000 objects can be seen with the naked eye.

"Cosmologists are having a field day. There has been a flood of data that allows them to finally put observations with theories," said Judy Jackson, the spokeswoman for collaboration of 11 universities and research institutes studying the data. That data, researchers hope, will eventually reveal what happened at the instant of the universe's creation.

CNNfyi.com Lesson Plan: New data from Sloan Digital Sky Survey     MESSAGE BOARD Stargazing

What is new about the Sloan Survey that it is not only able to see more objects in space, but that it maps in three dimensions -- giving scientists information about the distance of objects. Sloan scientists already have announced the discovery of the most distant objects ever observed in the universe: two new quasars, star-like objects known as the most luminous in the sky.

And, perhaps reducing doomsday asteroid fears, Sloan scientists have concluded there are far fewer small asteroids in the asteroid belt -- an area between Mars and Jupiter -- than previously thought.

"Since the asteroid belt is believed to be the reservoir for Earth-crossing asteroids, the new SDSS observations suggest that future asteroid collisions with Earth may be less likely than previously believed," Dr. Zeljko Ivezic of Princeton University, the leader of the survey's asteroid team, said in a news release.

The Apache Point Observatory

The early data also is giving scientists information about the expansion of the universe and the origin of different types of galaxies.

This first data package from the survey includes 500 gigabytes of images, precision measurements of some 14 million objects, and spectra of 50,000 galaxies and 5,000 quasars.

That information is now available to all astronomers, and by the fall, researchers hope to have a Web site that will give even novice sky-watchers understandable access to the heavens. The Sloan Survey telescope, dedicated in October of last year, is located at Apache Point Observatory in New Mexico.