Astronomers have discovered a new “hot Jupiter” planet with a strange, flattened and shifted orbit around its parent star. An exoplanet named TOI-1859 b was discovered by NASA satellite Transiting Exoplanet Survey Satellite (TESS), which detects planets by drops in light they cause when they cross or “pass” the face of their star. The team then continued this observation two more times using the ground-based facilities of the TESS Tracking Program. They confirmed the existence of the planet by observing it as it passed through its star, TOI-1859, located about 730 light-years from the Sun. systems.

Astronomers determined that TOI-1859 b takes about 64 Earth days to orbit its parent star, which is about 1.3 times its size. Sun. With an estimated diameter of about 78,000 miles (126,000 kilometers), the newly discovered exoplanet is slightly smaller than its namesake in the Solar System. Jupiterand almost 10 times larger than Earth.

Astronomers have yet to determine the mass of TOI-1859 b, but have found that the planet’s orbit is highly eccentric, or flat, and shifted relative to its star. The team said in a paper accepted for publication in The Astrophysical Journal Letters and published in the database, that the strange orbit of this hot Jupiter could be the result of interactions with other planets in the planet’s cosmic neighbourhood. arXiv.

The properties of the orbit are consistent with the multiple theory. gas giants They form around stars rich in “metals”, that is, elements heavier than hydrogen or helium, and then migrate to the outer regions of planetary systems. This migration is due to gravitational interaction between these planets, which, like TOI-1859 b, can leave gas giants remaining close to their stars with offset and eccentric orbits.

Alternatively, the team suggested that the planet’s orbit may have resulted from an encounter with a “brown dwarf” in the system. brown dwarfs They are often called “failure stars” because they are larger than gas giants but too small to trigger processes. nuclear fusionidentifies stars, and their discovery gives astronomers a better understanding of the line of mass that separates stars and planets.

hot but not hot

Any interaction that left TOI-1859 b in its current orbital state brought the planet within about 30 million miles (49 million km) of its host star – about a third of the distance between Earth and Earth. by the sun.

This exoplanet’s proximity to its star probably gives it a hotter surface temperature than our planet, making it a “hot Jupiter”. This class of world differs from the most common exoplanets, called hot Jupiters, which are closer to their parent star and usually orbit in just a few Earth days, or in some cases less than a day.

As the name suggests, hot Jupiters have a lower surface temperature than hot Jupiters, which can reach temperatures of 1,300 degrees Fahrenheit (725 degrees Celsius), hot enough to evaporate iron and create extreme conditions. For example, on an exoplanet WASP-76b Strong winds blow this iron vapor onto the night side of the planet, causing it to condense into iron droplets that rain down on the planet’s surface.

Many hot Jupiters are bound on their own. starsthat is, they have a permanent “day side” that is constantly surrounded by radiation from their parent star, and a permanent “night side” that faces colder – but still incredibly hot – space.

The team will further investigate TOI-1859 b’s planetary environment to discover the cause of its strange orbit. This will involve searching for other planets or brown dwarfs around the dwarf star TOI-1859. They will also look at whether the planet’s unusual orbit is due to the warmth of its host star, potentially revealing more about hot Jupiters.