About every 80 years, a new star appears in the night sky when a white dwarf experiences multiple explosions in the T CrB system, located about 3,000 light-years from Earth. (Image credit: NASA/Goddard Space Flight Center)
Research suggests that a bright new star could appear in the night sky later this week if a distant star system explodes as expected. However, scientists have been predicting the phenomenon to happen soon since early last year, suggesting that the long-awaited event is much harder to predict than previously thought.
T Coronae Borealis (T CrB) is a recurring nova that periodically explodes, creating frequent and fairly predictable bursts of light that can remain visible in our sky for up to a week.
These outbursts originate from a binary star system involving a massive red giant orbiting a superdense white dwarf about the size of Earth. The smaller star slowly pulls hydrogen gas from its companion and will eventually consume it over millions of years. However, as material builds up on the surface of the white dwarf, the pressure reaches a critical level and a powerful, bright explosion occurs. (This type of cyclic explosion is called a nova, and should not be confused with a supernova, in which a large star completely collapses, leaving behind only a compressed core.)
TCrB, also known as the “Blazing Star,” last flared up in our skies in 1946, but has been recorded at several points throughout its history, possibly dating back as far as 1217. By analyzing past outbursts, scientists have determined that a nova appears about every 80 years, meaning it should be happening any time now. However, we've already had several false alarms predicting the exact time it will appear.
Anticipation of a nova's imminent arrival began in late 2023, when the T CrB system dimmed, as it did before its 1946 outburst. But the excitement for this unique spectacle really began to build in 2024, first in March and then again in August, as various researchers claimed it was close. Since then, astronomers have been eagerly awaiting the Blaze Star's arrival — but it remains elusive.
The new Blaze Star begins to glow when an excess of stolen hydrogen accumulates on the surface of the white dwarf in the T CrB system.
However, in another study published last October in the journal Research Notes of the American Astronomical Society, a lone scientist proposed a different set of possible dates for the celestial event, after analyzing more detailed aspects of its previous outbursts.
The first potential window for the Blaze Star was pegged as beginning Thursday (March 27), study author Jean Schneider, an astronomer at the Paris Observatory in France, wrote. However, if the nova doesn't appear within a week of that date, we'll have to wait more than seven months for the next stellar outburst, he added.
In fact, the T CrB system has already exploded again, and we are just waiting for the light from the next explosion to reach us, crossing the 3,000 light years of space between it and us.
When will the new one appear?
Blaze Star is difficult to predict when it will reappear, as the time interval between each of its recorded outbursts can vary by an average of 1.4 years, and there is no pattern to indicate the direction of change. Therefore, researchers rely on monitoring the T CrB system to detect changes in brightness to predict its next appearance.
But in a previous study, Schneider reanalyzed the timing between the explosions and found that each interval matched almost perfectly the orbital period between the red giant and white dwarf, which orbit each other every 228 days. By that logic, the next nova should appear around March 27.
Sourse: www.livescience.com
