NASA\u2019s Transiting Exoplanet Survey Satellite (TESS) has unveiled TOI-4616 b, an Earth-sized planet orbiting a nearby M-dwarf star. Published in a March study on the preprint server arXiv, the findings reveal a rocky world situated just 91.8 light years from Earth, offering a rare opportunity to study a terrestrial planet in a nearby star system. This discovery marks a significant step in identifying planets with Earth-like conditions around stars that are not only common but also prime candidates for future atmospheric research.<\/p>\n
A New World Revealed: TOI-4616 B\u2019s Key Features<\/p>\n
The exoplanet TOI-4616 b is no ordinary find. Orbiting the mid-M dwarf star TOI-4616, it is an Earth-sized planet with a radius of 1.22 Earth radii, and an estimated mass between 1.5 and 3.0 Earth masses. Its orbital period is remarkably short, just 1.5 days, completing a full orbit in under two Earth days. With an equilibrium temperature of about 525 K (around 252\u00b0C or 485\u00b0F), TOI-4616 b exists in a zone where the radiation levels are extreme, a characteristic that offers a unique perspective on the environmental conditions of exoplanets near their stars.<\/p>\n
\u201cThe combination of precise stellar parameters, consistent multiband transit measurements, and the host star\u2019s brightness makes TOI-4616 a particularly valuable system for future atmospheric and dynamical studies,\u201d the researchers explain. <\/p>\n
This makes TOI-4616 b not just a discovery but a vital test case for models of atmospheric escape, volatile retention, and interior composition of planets exposed to intense stellar irradiation.<\/p>\n
![\"Stsci](\"https:\/\/www.newsbeep.com\/us\/wp-content\/uploads\/2026\/03\/STScI-01K1V61D55HJV2956SNSEN15GN_20260312_204851.webp.webp\")
This artist\u2019s illustration shows the TRAPPIST-1 system. It\u2019s a red dwarf that host seven rocky exoplanets, and four of them are likely in the habitable zone. The star\u2019s powerful flaring is represented in the image. The JWST hasn\u2019t found any evidence of atmospheres around any of these worlds yet.
Image Credit: NASA, ESA, CSA, STScI, Joseph Olmsted (STScI)<\/p>\n
Why M-Dwarf Stars Matter in the Search for Exoplanets<\/p>\n
M-dwarf stars like TOI-4616, smaller and cooler than our Sun, are among the most abundant types of stars in the galaxy. They are of particular interest to astronomers because their low luminosity and small size create ideal conditions for detecting Earth-sized planets. As noted in the study available on arXiv<\/a>,<\/p>\n \u201cRocky exoplanets are particularly abundant around M-type stars. Their small radii and low luminosities provide favorable conditions for detecting transiting terrestrial planets and probing their atmospheric properties.\u201d<\/p>\n These stars, which make up around 70% of the stars in our galaxy, present an exciting frontier for discovering new planets. Planets orbiting these stars are often subjected to strong radiation, making them valuable for understanding how atmospheres evolve and how planets respond to intense stellar activity.<\/p>\n TOI-4616 B: A Benchmark for Future Studies<\/p>\n The proximity of TOI-4616 b to Earth and the star\u2019s well-constrained characteristics offer a golden opportunity for comparative planetary studies. With the planet\u2019s unique attributes, researchers see it as an ideal benchmark for understanding how planets in similar conditions evolve, especially those exposed to extreme radiation.<\/p>\n \u201cWe report the discovery and statistical validation of TOI-4616 b, an Earth-sized planet transiting a nearby mid-M dwarf observed by the Transiting Exoplanet Survey Satellite (TESS),\u201d the authors write.<\/p>\n The planet\u2019s location places it in a regime that is intermediate between Earth-sized planets orbiting early M dwarfs and those orbiting ultra-cool stars, offering a rare vantage point for scientists.<\/p>\n![\"Tess](\"https:\/\/www.newsbeep.com\/us\/wp-content\/uploads\/2026\/03\/tess-discovers-a-new-e-1200x981.jpg\")
Target Pixel File (TPF) of TOI-4616 from TESS Sector 17. Credit:\u00a0arXiv\u00a0(2026). DOI: 10.48550\/arxiv.2603.10905<\/p>\n