The discovery: Water vapor in the atmosphere of planet TOI-674 b.
Key facts: This recently discovered planet, a bit bigger than NeptuneNeptune is the farthest planet from the sun. In our solar system, it is the fourth-largest planet by size, and third densest. It is named after the Roman god of the sea.”>Neptune and orbiting a red-dwarf star about 150 light-years away, places it in an exclusive club: exoplanets, or planets around other stars, known to have water vapor in their atmospheres. Many questions remain, such as how much water vapor its atmosphere holds. But TOI-674 b’s atmosphere is far easier to observe than those of many exoplanets, making it a prime target for deeper investigation.
Details: The planet’s distance, size, and relationship to its star make it especially accessible to spaceborne telescopes. At 150 light-years, it’s considered “nearby” in astronomical terms. The star itself, relatively cool and less than half as big around as our Sun, can’t be seen from Earth with the naked eye, but this too translates into an advantage for astronomers. As the comparatively large planet – in a size-class known as “super Neptune” – crosses the face of its smallish star, starlight shining through its atmosphere can be more easily analyzed by our telescopes. Those equipped with special instruments called spectrographs – including the just-launched James Webb Space TelescopeThe James Webb Space Telescope (JWST or Webb) is an orbiting infrared observatory that will complement and extend the discoveries of the Hubble Space Telescope. It covers longer wavelengths of light, with greatly improved sensitivity, allowing it to see inside dust clouds where stars and planetary systems are forming today as well as looking further back in time to observe the first galaxies that formed in the early universe.”>James Webb Space Telescope – can spread this light into a spectrum, revealing which gases are present in the planet’s atmosphere.
The discovery grew from a partnership between the tried-and-true Hubble Space TelescopeThe Hubble Space Telescope (often referred to as Hubble or HST) is one of NASA’s Great Observatories and was launched into low Earth orbit in 1990. It is one of the largest and most versatile space telescopes in use and features a 2.4-meter mirror and four main instruments that observe in the ultraviolet, visible, and near-infrared regions of the electromagnetic spectrum. It was named after astronomer Edwin Hubble.”>Hubble Space Telescope and TESSLaunched on April 18, 2018, aboard a SpaceX Falcon 9 rocket, NASA’s Transiting Exoplanet Survey Satellite (TESS) is a mission to search nearby stars for undiscovered worlds with a gold of discovering thousands of exoplanets around nearby bright stars.”>TESS, NASAEstablished in 1958, the National Aeronautics and Space Administration (NASA) is an independent agency of the United States Federal Government that succeeded the National Advisory Committee for Aeronautics (NACA). It is responsible for the civilian space program, as well as aeronautics and aerospace research. It’s vision is “To discover and expand knowledge for the benefit of humanity.””>NASA’s Transiting Exoplanet Survey Satellite, launched in 2018. The planet was first found by TESS, then its light spectrum was measured by Hubble. Data from the now-retired Spitzer Space Telescope also helped astronomers tease out some of the planet’s atmospheric components. If the Webb telescope, once it’s up and running, is turned on TOI-674 b, it should be able to examine the planet’s atmosphere in far more detail.
Only three other Neptune-sized exoplanets have had aspects of their atmospheres revealed so far, though the advent of telescopes like Webb promises a golden age in the study of exoplanetAn exoplanet (or extrasolar planet) is a planet that is outside the Solar System, orbiting around a star other than the Sun. The first suspected scientific detection of an exoplanet occurred in 1988, with the first confirmation of detection coming in 1992.”>exoplanet atmospheres.
Fun facts: The new planet can claim membership in another exclusive group: inhabitants of the so-called “Neptune Desert.” TOI-674 b orbits its small star so tightly that a “year” on this planet, once around the star, takes less than two days. But among the thousands of exoplanets confirmed in our galaxy so far, a strange pattern has emerged: Planets in the size-class between Neptune and JupiterJupiter is the largest planet in the solar system and the fifth planet from the sun. It is a gas giant with a mass greater then all of the other planets combined. Its name comes from the Roman god Jupiter.”>Jupiter are extremely rare in orbits of three days or less. The rarity of such planets, and the analysis of those that do turn up, could provide important clues to the formation of planetary systems in general – including our own.
The discoverers: An international team of scientists, led by Jonathan Brande of the University of Kansas, contributed to the new study of water vapor on TOI-674 b, which has been submitted to an academic journal. They included researchers from the NASA Ames Research Center and from IPAC and other research centers at Caltech.