The First Hycean World? JWST's Discovery of K2-18 b

To increase our chances of finding life on other planets, a systematic approach needs to be adopted, one that applies reasonable assumptions that maximize our success. So, an important question becomes, where should we point our telescopes? Show Notes Available at https://exoplanetradio.com/science/closest-exoplanets-with-life/.

Nothing lasts forever, stars live and die over the course of hundreds of millions to billions, and in the case of red dwarf stars, trillions of years. Planets are born from the remnants of their parent stars and die over a shorter timescale. Life on those planets, if it exists, is presumed to be shorter still, governed entirely by the environments provided by the combination of the star and planetary characteristics. How long life lasts there ultimately depends on how long the star lives and how it dies. Show Notes Available at https://exoplanetradio.com/science/how-long-life-earth/.

Over the course of this show, we’ve talked many many times about the Transit Method for detecting exoplanets. It is simply the measure of a star's decrease in brightness as the star passes through our line of sight. This once difficult measurement has now become commonplace and can even be done with advanced amateur astronomy equipment under a reasonably dark sky. Show Notes Available at https://exoplanetradio.com/science/exoplanet-secondary-eclipse/.

Meet TOI-1853 b, one of the weirdest exoplanets ever discovered! It's about the size of Neptune, but four times more massive. It orbits its star so closely that it completes a full orbit in just 1.24 days. This makes it very hot, and it's located in a region of space known as the 'hot Neptune desert', where astronomers have been looking for Hot Neptunes but unable to find any. Show Notes Available at https://exoplanetradio.com/exoplanets/toi1853b-baffling-exoplanet/.

In recent years, scientists have made great strides in the search for extraterrestrial life. They have discovered thousands of exoplanets. And some of them are located in the habitable zone of their star, which means that liquid water could exist on their surface and is essential for life as we know it. The search for life however, is a little more involved than finding planets, measuring their location and distance around the star and figuring out their location within a habitable zone. Astronomers need more information to learn if life may be there. Show Notes Available at https://exoplanetradio.com/science/biosignatures-search-for-life/.

The James Webb Space Telescope has completed observations of an exoplanet that may contain an ocean-covered surface underneath a hydrogen-rich atmosphere. This discovery provides a fascinating glimpse into a planet unlike anything in our Solar System, and raises interesting prospects about potentially habitable worlds elsewhere in the Universe. Show Notes Available at https://exoplanetradio.com/discoveries/first-hycean-world-jwst-discovery-k218b/.

On September 9, 1999, a team of astronomers from the High Altitude Observatory made a groundbreaking discovery. Using the radial velocity method, they detected a massive, Jupiter-sized planet orbiting a Sun-like star HD 209458. This was the first exoplanet to be discovered using this method, and since that fateful day, this system has become a champion of firsts. Show Notes Available at https://exoplanetradio.com/exoplanets/osiris-exoplanet-changed-everything/.

Deep in the cosmos, NASA's Transiting Exoplanet Survey Satellite (TESS) has discovered four new worlds orbiting a pair of young stars. These planets are providing scientists with a glimpse into a little-understood stage of planetary evolution - the time when atmospheres are being formed. Show Notes Available at https://exoplanetradio.com/science/glimpse-early-planet-formation/.

TRAPPIST-1e is a rocky, close-to-Earth-sized exoplanet orbiting within the habitable zone around the ultra-cool dwarf star TRAPPIST-1 approximately 40 light-years away from Earth in the constellation of Aquarius. Show Notes Available at https://exoplanetradio.com/exoplanets/trappist-1e-most-habitable-exoplanet/.

Based on our experience here on Earth, we know life here to be tenacious and ubiquitous. Even in the harshest climates, if we look hard enough, we can usually find some sort of life there. We are hoping the same is true on worlds around other stars, and recent research has begun looking into the question of whether life on other worlds could exist in the most inhospitable environs: the terminator zone of tidally locked planets. Show Notes Available at https://exoplanetradio.com/science/exoplanet-terminator-zones/.