Subscribe free to our newsletters via your
. 24/7 Space News .

Astronomers release unprecedented data set on celestial objects that brighten and dim
by Staff Writers
Pasadena CA (SPX) Jan 13, 2012

The data was taken with the 0.7-meter Catalina Schmidt Telescope on Mt. Bigelow in Arizona. Credit: The CSS Survey Team, University of Arizona.

Astronomers from the California Institute of Technology (Caltech) and the University of Arizona have released the largest data set ever collected that documents the brightening and dimming of stars and other celestial objects-two hundred million in total.

The night sky is filled with objects like asteroids that dash across the sky and others-like exploding stars and variable stars-that flash, dim, and brighten. Studying such phenomena can help astronomers better understand the evolution of stars, massive black holes in the centers of galaxies, and the structure of the Milky Way.

These types of objects were also essential for the recent discovery of dark energy-the mysterious energy that dominates the expansion of the universe-which earned last year's Nobel Prize.

Using the Catalina Real-Time Transient Survey (CRTS), a project led by Caltech, the astronomers systematically scanned the heavens for these dynamic objects, producing an unprecedented data set that will allow scientists worldwide to pursue new research.

"Exploring variable objects and transient phenomena like stellar explosions is one of the most vibrant and growing research areas in astrophysics," says S. George Djorgovski, professor of astronomy at Caltech and principal investigator on the CRTS. "In many cases, this yields unique information needed to understand these objects."

The new data set is based on observations taken with the 0.7-meter telescope on Mt. Bigelow in Arizona. The observations were part of the Catalina Sky Survey (CSS), a search for Near-Earth Objects (NEOs)-asteroids that may pose a threat to Earth-conducted by astronomers at the University of Arizona.

By repeatedly taking pictures of large swaths of the sky and comparing these images to previous ones, the CRTS is able to monitor the brightness of about half a billion objects, allowing it to search for those that dramatically brighten or dim. In this way, the CRTS team identified tens of thousands of variables, maximizing the science that can be gleaned from the original data.

The new data set contains the so-called brightness histories of a total of two hundred million stars and other objects, incorporating over 20 billion independent measurements.

"This set of objects is an order of magnitude larger than the largest previously available data sets of their kind," says Andrew Drake, a staff scientist at Caltech and lead author on a poster to be presented at the meeting of the American Astronomical Society in Austin on January 12. "It will enable many interesting studies by the entire astronomical community."

One of the unique features of the survey, Drake says, is that it emphasizes an open-data philosophy. "We discover transient events and publish them electronically in real time, so that anyone can follow them and make additional discoveries," he explains.

"It is a good example of scientific-data sharing and reuse," Djorgovski says. "We hope to set an example of how data-intensive science should be done in the 21st century."

The data set includes over a thousand exploding stars called supernovae, including many unusual and novel types, as well as hundreds of so-called cataclysmic variables, which are pairs of stars in which one spills matter onto another, called a white dwarf; tens of thousands of other variable stars; and dwarf novae, which are binary stars that dramatically change in brightness.

"We take hundreds of images every night from each of our telescopes as we search for hazardous asteroids," adds Edward Beshore, principal investigator of the University of Arizona's asteroid-hunting CSS.

"As far back as 2005, we were asking if this data could be useful to the community of astronomers. We are delighted that we could forge this partnership. In my estimation, it has been a great success and is a superb example of finding ways to get greater value from taxpayers' investments in basic science."

The team says they soon plan to release additional data taken with a 1.5-meter telescope on Mt. Lemmon in Arizona and a 0.5-meter telescope in Siding Spring in Australia.

In addition to Djorgovski, Drake, and Beshore, the team includes staff scientist Ashish Mahabal, computational scientist Matthew Graham, postdoctoral scholar Ciro Donalek, and research scientist Roy Williams from Caltech. Researchers from other institutions include Steve Larson, Andrea Boattini, Alex Gibbs, Al Grauer, Rik Hill, and Richard Kowalski from the University of Arizona; Mauricio Catelan from Universidad Catholica in Chile; Eric Christensen from the Gemini Observatory in Hawaii; and Jose Prieto from Princeton University. The Caltech research is supported by the National Science Foundation. The work done at the University of Arizona is supported by NASA.


Related Links
California Institute of Technology
Stellar Chemistry, The Universe And All Within It

Comment on this article via your Facebook, Yahoo, AOL, Hotmail login.

Share this article via these popular social media networks DiggDigg RedditReddit GoogleGoogle

Memory Foam Mattress Review
Newsletters :: SpaceDaily :: SpaceWar :: TerraDaily :: Energy Daily
XML Feeds :: Space News :: Earth News :: War News :: Solar Energy News

Before they were stars
Boston MA (SPX) Jan 12, 2012
The stars we see today weren't always as serene as they appear, floating alone in the dark of night. Most stars, likely including our sun, grew up in cosmic turmoil - as illustrated in a new image from NASA's Spitzer Space Telescope. The image shows one of the most active and turbulent regions of star birth in our galaxy, a region called Cygnus X. The choppy cloud of gas and dust lies 4,50 ... read more

Lunar orbiter spots moisture locations

'Mini moons' may surround Earth

Rare Moon mineral found in Australia

Ecliptic Shoots for Moon at End of a Record Year

Mars Express spots wrinkle ridges and grabens in Tempe Terra

Mars Science Lab Completes Biggest Maneuver On Route To Mars

Stranded Mars probe to crash into ocean Sunday: Russia

Russia was well aware of Phobos-Grunt mission risks

The gadgets which stood out at CES

Smart appliances set to transform the home

Boeing begins NASA solar electric propulsion study

Solid state Swiss Army Knife can save digital lives

China launches Ziyuan III satellite

Spying on Tiangong

China's space ambitions ally glory with pragmatism

Why The X-37B Is Not Spying On Tiangong

ISS Team Undertakes 'EPIC' Event

Photographing the International Space Station from Your Own Backyard

New crew arrives at international space station

NASA 'Smart SPHERES' Tested on ISS

Canaveral has busy 2012 launch schedule

China to launch Bolivian satellite in 2013: Chinese Ambassador

Ariane 5, Soyuz, Vega: Three world-changing launch vehicles

Satellites: Europe's Arianespace sets 13 launches for 2012

Scientists Discover a Saturn-like Ring System Eclipsing a Sun-like Star

Planets around stars are the rule rather than the exception

Milky Way teaming with 'billions' of planets: study

Kepler Mission Finds Three Smallest Exoplanets

Lens makers focus on smartphone cameras

CES gadgets bringing the "Matrix" to life

Apple suspends iPhone sales at China stores

ESA Coordinates International Satellite Reentry Campaign For Phobos-Grunt

The content herein, unless otherwise known to be public domain, are Copyright 1995-2014 - Space Media Network. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA Portal Reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. Advertising does not imply endorsement,agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. Privacy Statement