New Stars on the Cosmic Block Are Fast, Bright and Pulsating
By Passant Rabie 11 hours ago Science & Astronomy
It's a whole new class of stars!
The nebulous remains of a dying subdwarf O star as seen from the European Southern Observatory's Very Large Telescope.(Image: © ESO)
Astronomers have stumbled upon a new class of pulsating stars, which change brightness every 6 to 8 minutes with a range of around 10% — much faster and more varied than any other variable stars observed before.
Many stars pulsate, slightly fluctuating their brightness as their outer layers expand and contract. But the scientists were struck by the rate and range of changing brightness observed in four hot subdwarf pulsating stars. Subdwarfs are stars with lower luminosity and mass.
"It was really hard to distinguish them from any other thing we have seen before," Thomas Kupfer, a postdoctoral scholar at the University of California, Santa Barbara, and lead author of the study, told Space.com. "The brightness change was very, very large, more than 10%, which has not been seen in similar types of stars." Stars usually change brightness by 1-2%, he added, including our own sun.
The four subdwarf stars are one-tenth the size of the sun and are very hot while simultaneously being compact. Their temperatures reach up to 90,000 degrees Fahrenheit (50,000 degrees Celsius), while the sun's surface temperature is around 10,000 F (5,538 C).
More:
https://www.space.com/new-class-of-pulsating-stars-discovered.html
= new reply since forum marked as read
i blame daniel quinn for that. 
