One of the most intriguing mysteries in planet science could be revealed by a newly discovered exoplanet located just 200 light-years from Earth.
The radius of Earth is about 1.8 miles. The object being named TOI-1075b It is one of the most prominent examples of a super-Earth planet we have found. It also Sits solidly in the what we call small-planet radius gap;There is a apparent shortage of planets with radii between 1.5 and 2 Earth.
Smaller rocky super-Earths They have been discovered. These worlds are slightly larger and have puffy atmospheres. mini-Neptunes. However, the area between is a bit deserted.
The added girth isn’t just puff. TOI-1075b is 9.95 times heavier than Earth. This is way too heavy for a gaseous universe. Mercury, Earth, MarsAnd Venus. This unique property makes it an excellent candidate for probing theories about planetary formation or evolution.
The small-planet distance gap was not discovered until 2017 when we had a better understanding of the phenomenon. Large enough exoplanet databaseFor scientists to see a pattern, they need extrasolar or other planets. Very few exoplanets found within close proximity to their stars have found worlds that cross that gap.
This could be due to a variety of reasons. The most common explanation is that an exoplanet below a certain size doesn’t have enough mass to sustain an atmosphere against the evaporative radio radiation so close to its host star. This model suggests that exoplanets located in the gap should have a substantial atmosphere primarily composed of hydrogen and helium.
Enter TOI-1075b. It was detected by data from NASA’s exoplanet searching telescope, TESS. The short version is Transiting Exoplanet Survey SatelliteTESS searches for faint, periodic dips of light from other stars, which could indicate that these stars may be orbited. Astronomers also use the star’s dimming to determine the radius of the exoplanet.
The Data TESSAccording to some theories, the orbital period of the exoplanet orbiting the orange dwarf star TOI-1075 is approximately 14.5 hours. This caught the attention of Zahra Esack, an astronomer at MIT who studies hot super-Earths. This radius and its proximity made the world the candidate world for the radius-gap criteria.
To understand the exoplanet’s nature, we needed to weigh it. This requires leveraging an exoplanet’s gravitational effect on its host star. The star supplies most of the gravity for a star-planet interaction, but the planet exerts some gravitational pull back on the star as well. This means that a star can wobble very slightly on the spot. Astronomers can detect it in Very small changes in star’s light.
Knowing the mass and radius of the star can help us to determine the mass of any planet that is jiggling with it. Because TOI-1075’s radius and mass are about 60% smaller than our Sun, Essack and her colleagues were capable of accurately calculating the exoplanets mass at 9.95 Earth masses. Their precise measurements of the size yielded 1.791 Earthradii.
You can calculate the average density of an item if you know its size and weight. How about TOI-1075b. This was an absolute chonk. Its density is 9.32 grams/ccm2. It is nearly twice the density of Earth, at 5.51 grams per square centimeter. This makes it a contender to be the super-Earth with the highest density.
A substantial hydrogen-helium atmosphere should be present on an exoplanet located in the mass gap. The density of TOI-1075b is inconsistent with a substantial atmosphere. This is quite curious. However, it is possible that the exoplanet could have something even more interesting.
“Based upon TOI-1075b’s prediction of composition and the ultra-short orbital time, we don’t expect the planet has retained a H/He environment.” The researchers wrote in their paper.
“But, TOI-1075b might have: no atmosphere (bare rocks); a metal/silicate atmosphere with a composition created by the vaporizing magma ocean on the surface since TOI-1075B’s equilibrium temperature of 1045.55 b is hot enough to melt a rock surface; or, particularly at the low-end, possibly a thin H/He/CO2“
You read it right. ToI-1075b’s surface is so hot, due to being so close its star, that it could be an ocean magma producing an atmosphere of rock vaporization.
We might be able to find out. As we’ve already mentioned, This was only recently discoveredJWST is incredibly adept at peering into exoplanet atmospheres. Pointing it at TOI-1075b should reveal if it has a thin atmosphere, a silicate atmosphere, or no atmosphere at all – and this information could reveal some previously unknown quirk of planet formation and evolution, and how super-Earths lose their gas.
The research of the team has been accepted by The Astronomical JournalIt is also available online arXiv.
