This first floor of Corona Borealis shows the position of T Crb with a green point. At this point of view, North is at the top and is left east. Credit: Alison Klesman (via Theskyx)
If I am honest, the title of this story should be “When I exploded T Coronae Borealis Still? “
T Coronae Borealis (T Crb) is classified as a recurring Nova – a star that blows the top more and several times. These objects are rare; Less than a dozen have been identified in our galaxy. And despite the forecasts that would explode last year, we are still waiting.
For now.
Because T Crb explodes
T Crb is part of a binary system in which a white dwarf and a red giant orbit each other. The red giant, close to the end of his star life, is continuing to lose hydrogen, some of which falls on the white dwarf. While the smaller star collects this gas, the pressure and temperature on its surface increases until the hydrogen turns on and, boom!
That boom happens approximately every 80 years. In fact, the last time a terrestrial saw t crb with the eyes was in 1946, the year of his last outburst. Normally, it is around the tenth magnitude, about 40 times too weak to be detected also observers of sky even seasoned. (Furthermore, in the event that you are curious, the first time it was seen – or, at least, recorded – it was in the distant 1217.)
What we will see
When the star has its outburst, it will increase in brightness to the second size, the same as that of the North Star, also known as Polaris. How long will it remain so bright? Less than a day. Yes, that’s all. As soon as you read to explode, start making plans to go out that night. It could remain visible in the naked eyes for a few days, but there are no guarantees about it.
This column of Stephen James O’Meara contains a comparison side by the side of how the boreal crown will appear to the naked eye when it is visible CRB.
Because we still think that it will explode soon
In April 2024, the observers noticed a dip in the brightness of T Crb. Such a dip is usually followed by the explosion a few months later. Most scientists agreed that September was the most likely month. But September came and left and did not happen, at least when writing this document.
Precisely this month, however, a team of scientists who use the Alfred Jensch telescope in TaUtenburg, Germany, has seen an increase in the strength of different lines in the CRB spectrum. This indicates that the white dwarf is accumulating the matter at an increased rhythm, a state that should precede the explosion. They had previously noticed it in November 2024 and that discovery corresponded to a slight increase in the brightness of the star.
So far, however, there is no illumination of T Crb associated with the strengthening of the current ghost line. But the news has alerted teams of astronomers all over the world.
How to find T Crb
The position of T Crb is easy to find. It is located south of a line between the two brightest stars in the northern sky, Arcurus and Vega. Starting from Arcurus, T Crb is about a third of the journey to Vega, even if a little under that line. As the name indicates, the Boreal Coronae is within the boundaries of the constellation of Boreal crown the northern crown. It is located about 5½ ° east of the brightest star of that star, Alphecca.
So, keep your eyes on Astronomy.com for the news that T Crb has become briefly bright enough to observe. So run out that night and look at a show that you will never see again.
