In what is being described as a “once in a lifetime event”, light from a thermonuclear explosion on a star has been heading towards Earth for thousands of years and could reach it any day.
T Coronae Borealis (also known as T Cor Bor, T CrB, and the Blaze Star) will be about as bright as the North Star (for those in the Northern Hemisphere).
Dr Laura Driessen, from the University of Sydney's School of Physics, said for those in the Southern Hemisphere, the Blaze Star would be as bright as Orion's right foot.
T CrB is a recurring nova, appearing approximately every 80 years following a thermonuclear explosion on the surface of a white dwarf located about 3,000 light-years away.
The dwarf star sucks hydrogen from the neighboring red giant, and this creates pressure and heat that eventually triggers an explosion.
It's known as a nova (meaning “new”), and is expected to become visible any time between now and September.
There is a dark spot in the Corona Borealis. Astronomers and non-astronomers everywhere are tracking the location where the “new” star will appear. It will be visible to the naked eye for about a week.
NASA called it a “once in a lifetime event.”
Driessen said the two stars are so close that gravity causes the white dwarf star to pull material in.
“It is a binary system and it explodes from time to time, so it is a novel system,” he said.
“When we think of novae we often think of supernovae, which is when they explode at the end of their lives … there's no coming back from that. But novae have small explosions on the surface, which are based on this accretion, this aggregation of matter.”
According to NASA, the first recorded sighting of a blazing star was in 1217, when the Abbot of Ursberg in Germany observed “a faint star that shone with a very bright light for a short time.”
It was last seen in 1946.
The star is always variable, getting brighter and dimmer, Driessen said. But it starts to brighten a bit about 10 years before an explosion, then fades again in the months before the blast.
“It's not really clockwork, it's about the build-up of content. So it's not an exact number, but we get this early warning,” he said.
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Although this amazing phenomenon has been observed before, Driessen said this is the first time it will be studied with modern technology.
“That's why it's so exciting. This will be the first program where we'll get the information that we can get now, with all the telescopes we have that we didn't have 80 years ago,” he said.
NASA's Fermi Gamma-ray Space Telescope, the James Webb Space Telescope, and the National Radio Astronomy Observatory's Very Large Array in New Mexico are some of the instruments that will be tracking the blaze.
Fermi project scientist Dr. Elizabeth Hess, who also heads NASA's Astroparticle Physics Laboratory, said typical nova events are still a long way off.
“It will be very close, there will be a lot of eyes on it, studying it at different wavelengths and hopefully that will give us data to understand the structure and the specific processes involved,” he said.
“We can't wait to get the full picture of what's going on.”
NASA has a map of the Corona Borealis to help people figure out where to look, and Driessen said software like Stellarium is also useful. There are several free apps for viewing maps of the night sky.
Driessen said people should find the darkest area possible, as far away from a city or town as possible, and use binoculars to get a better view.
“Adjust your eyes to the dark,” he said. “And it's good to have a red flashlight. Put a bit of cellophane on it so it doesn't ruin your night vision. And don't look at your phone.”