In 2020, astronomers made a remarkable discovery when they observed a Red Nova, an immensely powerful event that falls on the less energetic side of cosmic occurrences. However, a recent study conducted by an astronomer has provided a close examination of this event and led to the conclusion that what we witnessed was actually a star annihilating its own planet.
The technical term used to describe these Red Nova events is “intermediate luminosity optical transits” or ILOTs. These occurrences are incredibly rare to observe due to their relatively moderate energy output. Consequently, capturing them in observations poses a challenge for scientists. Despite their rarity, astronomers suspect that these events happen frequently throughout the universe.
For years, astronomers have pondered whether these Red Novas occur as a result of planets being engulfed by their parent stars. Several candidates exhibiting ILOT characteristics have been closely examined with this scenario in mind. However, astronomers have encountered difficulties in aligning theoretical predictions of this scenario with actual observational results.
However, this new observation, known as ZTF SLRN-2020, may be the perfect match. Previous instances of suspected interactions between stars and planets have occurred in very young systems, where planets are on chaotic trajectories, colliding with each other and occasionally plunging into their stars. In contrast, in this case, the star belongs to the main sequence, indicating that it is a typical middle-aged star.
Based on theoretical calculations, the astronomer conducting the study concluded that the planet’s proximity to its star was not a straightforward scenario of the planet simply slipping into the star’s atmosphere and concluding the event. Instead, it went through multiple violent phases as the planet was torn apart, leading to the flare of the Red Nova.
As the planet approached the star, it underwent a process of intense heating, causing its outer layers to transform into plasma. The intricate interplay of electricity and magnetism within this plasma resulted in the ejection of a pair of jets away from the planet while it orbited the star. However, these jets lacked sufficient power to completely overcome the gravitational influence of the star, causing the material to eventually fall back down.
However, despite the planet regaining some of its lost mass through the jets, it experienced further mass loss due to the intense energies near the surface of the star. Prior to complete engulfment, it is possible that the planet formed an accretion disk around the star. Material from the destroyed planet gradually leaked and funneled into the star until everything came to an end. Interestingly, the accretion disk itself had the ability to launch its own jets, which could push away from the star, expanding and forming a nebula that extended away from the system.
Undoubtedly, the interaction between the planet and the star during its engulfment unleashed an astonishing amount of energy, ultimately resulting in the Red Nova phenomenon. The specifics of this system and how the planet ended up in such a fateful position are still unknown to us. Astronomers are eager to discover additional instances of these less energetic transient events, as they hold the potential to deepen our understanding of the intricate relationships between planets and their parent stars.