The planet: TOI-1231 b
The discovery: A planet some 90 light-years away from Earth is oddly reminiscent of our own 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 – that is, a gaseous world with a potentially rich atmosphere, ripe for study. The planet is more than 3 ½ times as big around as Earth and warm by Earthly standards at 134 degrees FahrenheitThe Fahrenheit scale is a temperature scale, named after the German physicist Daniel Gabriel Fahrenheit and based on one he proposed in 1724. In the Fahrenheit temperature scale, the freezing point of water freezes is 32 °F and water boils at 212 °F, a 180 °F separation, as defined at sea level and standard atmospheric pressure. ”>Fahrenheit (57 CelsiusThe Celsius scale, also known as the centigrade scale, is a temperature scale named after the Swedish astronomer Anders Celsius. In the Celsius scale, 0 °C is the freezing point of water and 100 °C is the boiling point of water at 1 atm pressure.”>Celsius). But astronomers say it is one of the “coolest,” comparatively small planets known to date, and in a prime position for the components of its atmosphere to be teased apart by space telescopes.
Key facts: TOI-1231 b orbits a red-dwarf star – smaller but longer lived than our own Sun – with a year, once around the star, that is 24 days long. But the planet stays relatively cool despite its close orbit because its star also is on the cooler side. Though not habitable due to its size, the planet could offer scientists one of their first chances to capture a “bar-code” type reading of the atmosphere of a temperate, Neptune-sized 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 – a planet orbiting another star. This will allow comparisons with similar worlds elsewhere in the galaxy, bringing potentially deep insights into the composition and formation of exoplanets and planetary systems, including our own.
Details: A new era in the study of exoplanets is just beginning, as we move from simply detecting these planets, and counting them up, to zeroing in on individual worlds to analyze their atmospheres. With a technique called transmission spectroscopy, scientists should be able to use the 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 soon the far more sensitive 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 – to capture starlight shining through the atmosphere of TOI-1231 b. Molecules in this planet’s atmosphere will absorb slices of light from this spectrum, leaving dark lines that can be read like a bar-code, revealing which gases are present.
The planet’s red-dwarf star, though small, is quite bright in the infrared part of the light spectrum, or light beyond the red end of the spectrum that can’t be seen with the naked eye. It is, however, ideal for investigation by Hubble and Webb. Also helpful: From our perspective on Earth, TOI-1231 b crosses the face of its star, which allowed its detection in the first place by 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 (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). And that crossing, called a “transit,” takes nearly 3 ½ hours – plenty of time to capture and analyze starlight shining through the planet’s atmosphere.
Fun facts: We might see evidence of clouds (perhaps even made of water) in this planet’s atmosphere. And because this star-and-planet system is moving at a high velocity away from Earth, hydrogen atoms escaping from the planet’s atmosphere might be readily detected. In other words, the planet could turn out to have a tail.
In general, such atoms are almost impossible to detect even when using space-based facilities; their presence is masked both by the outer wisps of Earth’s atmosphere and by interstellar gas. But the TOI-1231 system is moving so quickly that escaping hydrogen atoms are shifted out of phase with the blocking material, where they could be detected by telescopes like Hubble.
The discoverers: Using data from TESS, a large, international team of astronomers led by Dr. Jennifer Burt, an exoplanet researcher at NASA’s Jet Propulsion Laboratory in Southern California, and Professor Diana Dragomir, an exoplanet researcher at the University of New Mexico, announced the discovery of TOI-1231 b in a new paper. The discovery was entered into NASA’s Exoplanet Archive on June 3.
For more on this discovery, read New Neptune-Sized Exoplanet Discovered With a Substantial Atmosphere Ripe for Study.
Reference: “TOI-1231 b: A Temperate, Neptune-Sized Planet Transiting the Nearby M3 Dwarf NLTT 24399” by Jennifer A. Burt, Diana Dragomir, Paul Mollière, Allison Youngblood, Antonio García Muñoz, John McCann, Laura Kreidberg, Chelsea X. Huang, Karen A. Collins, Jason D. Eastman, Lyu Abe, Jose M. Almenara, Ian J. M. Crossfield, Carl Ziegler, Joseph E. Rodriguez, Eric E. Mamajek, Keivan G. Stassun, Samuel P. Halverson, Steven Jr. Villanueva, R. Paul Butler, Sharon Xuesong Wang, Richard P. Schwarz, George R. Ricker, Roland Vanderspek, David W. Latham, S. Seager, Joshua N. Winn, Jon M. Jenkins, Abdelkrim Agabi, Xavier Bonfils, David Ciardi, Marion Cointepas, Jeffrey D. Crane, Nicolas Crouzet, Georgina Dransfield, Fabo Feng, Elise Furlan, Tristan Guillot, Arvind F. Gupta, Steve B. Howell, Eric L. N. Jensen, Nicholas Law, Andrew W. Mann, Wenceslas Marie-Sainte, Rachel A. Matson, Elisabeth C. Matthews, Djamel Mékarnia, Joshua Pepper, Nic Scott, Stephen A. Shectman, Joshua E. Schlieder, François-Xavier Schmider, Daniel J. Stevens, Johanna K. Teske, Amaury H.M.J. Triaud, David Charbonneau, Zachory K. Berta-Thompson, Christopher J. Burke, Tansu Daylan, Thomas Barclay, Bill Wohler and C. E. Brasseurs, Accepted, The Astronomical Journal.
arXiv: 2105.08077
Source: SciTechDaily