A worldwide network of telescopes is spending time every night watching the odd death throes of a star very much like the sun.
The project is the latest in an elaborately choreographed collaboration called the Whole Earth Telescope. It includes observatories in China, South Korea, Taiwan, Poland, Austria, Italy, South Africa, Chile, Germany, Lithuania, India, New Zealand, France, the Netherlands, Canary Islands, Russia, Austria and the United States.
"You have to apply for time at each telescope separately, so it's pretty complicated," said Judith Provencal, an assistant professor of physics and astronomy at the University of Delaware, which has been coordinating Whole Earth Telescope observations for three years.
The network, which presently includes 22 observatories, began in 1986 at the University of Texas at Austin.
About once a year, astronomers select a primary target for nightly studies. Last week, the Whole Earth Telescope began watching a dying sun-like star known as a white dwarf, which is located in the constellation Ophiuchus.
White dwarfs are the collapsed remains of stars about the size of the sun that have run out of material to sustain nuclear reactions.
Like many white dwarf stars, the Whole Earth Telescope target, known as WDJ1524-0030, pulsates as it depletes its fuel. But it has developed an odd rhythm; in April, its pulse rate quickened. On its new cycle the star is pulsating about every 500 seconds. It previously pulsed at intervals of about 1,000 seconds, Provencal said.
The shift is likely due to a temperature change, Provencal said.
"Figuring out why is going to be fun," she added.
The idea behind the Whole Earth Telescope is to gather near-continuous observations of a target star as long as it is visible from Earth. Since it is always dark somewhere, the targets should be under 24-hour watch, provided weather or technical problems don't interfere with observations.
"When you need to study a target for long periods of time, you really have no choice but to collaborate if you're on Earth," said Travis Metcalfe, who worked on Whole Earth Telescope projects as a graduate student at University of Texas.
Unlike other collaborative observation programs, Whole Earth Telescope managers attempt to analyze the data real time so that the observations can be tweaked if necessary.
"I'm looking at data from India right now," Provencal told Discovery News.
Waiting in the queue are observations from Texas and the Kitt Peak National Observatory in Arizona.
Observations of WDJ1524-0030 should last until June 11.
Not too much is known about the star, which was discovered in 2004 by the Sloan Digital Sky Survey.
"Stars of this type have all kinds of variability," Metcalfe said.
