What To Know
- This star, far from being ordinary, is a red giant in an advanced phase of its evolution, which adds additional complexity to the study of this planet.
- Indeed, contrary to expectations based on our current theories, which predict that planets located so close to their star quickly lose their atmosphere due to the intense flux of stellar particles and extreme heat, Phoenix has visibly maintained an atmosphere noticeably extended and light.
- Researchers believe that this interaction could lead to the destruction of the planet in about 100 million yearswhen its orbit becomes unstable and it is swallowed up by the star’s enormous gaseous envelope.
The discovery of a world nicknamed Phoenix challenges our current theories about planetary evolution. Astronomers don’t know how the world manages to maintain its atmosphere so close to its star.
Remarkable features
Phoenix, scientifically known as TIC365102760 bis a fascinating planet nestled in an orbit six times closer of his star that Mercury is not the Sun. This star, far from being ordinary, is a red giant in an advanced phase of its evolution, which adds additional complexity to the study of this planet. Its proximity to such a star then raises intriguing questions about the dynamics of its atmosphere and its evolutionary history. Indeed, contrary to expectations based on our current theories, which predict that planets located so close to their star quickly lose their atmosphere due to the intense flux of stellar particles and extreme heat, Phoenix has visibly maintained an atmosphere noticeably extended and light. Furthermore, what makes Phoenix even more unique is its size. With a dimension 6.2 times that of Earthit is classified as a Neptune-like planet. However, while other planets in this class are characterized by dense and compact atmospheres, its exceptionally low density sets it apart from all other hot Neptunes known to date. This singularity raises a crucial question: how could such a massive planet, located in such an extreme environment, have maintained such an extensive and light atmosphere? The discovery and study of Phoenix thus sheds light on our incomplete understanding of the evolution of planetary systems. Future observations could help to understand the mechanisms underlying this enigma.
Credits: Nazarii Neshcherenskyi/istock
A glimpse into the future of the solar system
Red giants, such as the star Phoenix orbits, are at the end of their lives and are characterized by their spectacular expansion. When a star like this one enters its red giant phase, it swells to become hundreds or even thousands of times larger than its original size. This massive expansion has dramatic repercussions for its companion planets. In Phoenix’s case, its proximity to a red giant means that it is subject to intense gravitational forces and stellar tides. Over time, these forces could pull Phoenix into a gravitational spiral toward its host star. Researchers believe that this interaction could lead to the destruction of the planet in about 100 million yearswhen its orbit becomes unstable and it is swallowed up by the star’s enormous gaseous envelope. This prospect offers an intriguing glimpse into what might await our own solar system in the long term. In about 5 billion years, when the Sun reaches the end of its life and enters its red giant phase, Earth could indeed suffer a similar fate, after Mercury and Venus. Details of the study are published in The Astrophysical Journal.
