Astronomers are predicting the imminent occurrence of a rare phenomenon: a nova may soon appear in our sky in the coming months. A star that is currently inaccessible to us will then become easily visible to the naked eye.
In our sky, it sometimes happens that stars suddenly become very bright. This phenomenon lasts for a few days. Astronomers then classify the star in question as a nova. The name comes from a time when the star appeared new to the observers’ eyes. Researchers have been monitoring a system located about 3,000 light-years from our Earth that they suspect may soon offer us such an experience.
A White Dwarf and a Red Giant to Produce a Nova
The system in question consists of a red giant and a white dwarf, known as T Coronae Borealis (T CrB). Both are heavier than our Sun. The unstable red giant regularly ejects matter. The white dwarf, in turn, pulls this matter towards itself. This interaction is enough to trigger uncontrolled thermonuclear reactions that boost the system’s brightness (usually not more than what one would observe for a typical variable star). The system’s usual magnitude is around 10, indicating very low brightness, although in 2016, the brightness of T CrB nearly tripled – yet remained invisible to the naked eye.
It has happened before that the brightness of T Coronae Borealis increased thousands of times, making it visible to terrestrial observers. Once in 1866. Then in 1946. A quick calculation gives hope that a nova will appear again very soon, especially since astronomers report that before the 1946 event, the star had undergone a noticeable attenuation. They now note that it has just done the same.
A New Pole Star
Therefore, researchers believe that we should expect to be able to observe the nova between February and September of this year 2024. The magnitude of T Coronae Borealis would then drop to only 2. This would be an equivalent brightness to that of the Pole Star. All this will happen in the constellation known as the Northern Crown, a fairly easily identifiable small arc.