A team of international astronomers has discovered a new super-Neptune exoplanet, named TOI-5005 b, orbiting a star similar to our sun.
This new planet is about six times larger and more than 30 times heavier than Earth.
The discovery was detailed in a recent paper published on September 26, 2024, on the pre-print server arXiv.
The planet was found using data from NASA’s Transiting Exoplanets Survey Satellite (TESS), which aims to identify planets outside our solar system by observing over 200,000 stars near the sun.
So far, TESS has identified more than 7,200 candidate planets, with 557 confirmed.
Led by Amadeo Castro-González from the Astrobiology Center in Madrid, Spain, the team noticed a signal in the light emitted by the star TOI-5005, located 685 light years away from Earth.
This signal, caused by the planet passing in front of its star, was confirmed as a planet through follow-up observations using several ground-based telescopes.
TOI-5005 b is considered a super-Neptune because of its size and characteristics. It has a radius 6.25 times that of Earth and a mass 32.7 times greater.
The planet orbits its star in just 6.31 days, much closer than Earth’s orbit around the sun, at a distance of about 0.066 AU (Astronomical Units). The surface temperature of the planet is estimated to be 1,040 K (about 767°C or 1,413°F).
The planet’s low density (0.74 g/cm³) suggests that it has a large, gaseous envelope surrounding its core.
Researchers believe that TOI-5005 b likely formed through a process called core accretion, where a planet slowly gathers gas and dust until it becomes a massive body.
TOI-5005 b belongs to a rare group of low-density Neptune-like planets located in a region known as the “Neptunian savanna,” where Neptune-sized planets with short orbital periods are uncommon.
This is different from the “Neptunian desert,” where very few Neptune-like planets are found due to their proximity to their stars.
The brightness of the star TOI-5005 makes this newly discovered planetary system a promising target for further studies, especially in exploring the atmosphere and structure of TOI-5005 b. This discovery offers exciting opportunities for scientists to better understand Neptune-like exoplanets and their formation.
