View larger. | Artist’s idea of an Earth-sized exoplanet, on this case LP 791-18 d, some 90 light-years away. Proof suggests it’s a volcano-covered world, maybe as lively as Jupiter’s moon Io. So, what’s a planet? Picture by way of NASA/ Goddard House Flight Heart/ Chris Smith (KRBwyle).
On Monday, July 22, 2024, EarthSky’s Deborah Byrd will communicate LIVE with Jean-Luc Margot, a Belgian-born astronomer and UCLA professor. Margot and his crew simply printed a brand new examine, outlining the rationale we’d like a brand new definition of “planet.” They’ll current their concepts to the IAU Basic Meeting – a world assembly of astronomers – starting on August 6 in Cape City, South Africa.
When Pluto was demoted from full planet standing in 2006, it was as a result of the Worldwide Astronomical Union’s definition of a planet had modified. The change created an uproar. However, for the reason that mid-Nineteen Nineties, scientists have found greater than 5,000 exoplanets, or worlds orbiting distant stars. In the meantime, the IAU definition applies solely to planets inside our solar system. The newly proposed planet definition is much less sun-centric.
The brand new definition specifies that “planets” might orbit a number of stars, brown dwarfs or stellar remnants.
It units mass limits that its originators say ought to apply to planets in all places.
However does it return Pluto to full planet standing?
Jean-Luc Margot and crew printed a brand new examine in The Planetary Science Journal this previous week (July 17, 2024) outlining their causes for the urged change within the definition to “planet.” Discover their examine right here: Quantitative Criteria for Defining Planets.
Jean-Luc Margot is a Belgian-born astronomer and UCLA professor. He obtained a B.S. in electrical engineering from the College of Louvain (1993) and a Ph.D. in astronomy from Cornell College (1999). His analysis pursuits embody the dynamics and geophysics of planetary our bodies, radio and radar astronomy, and SETI. Picture by way of The Planetary Society/ Jean-Luc Margot. Used with permission.
Backside line: When the Worldwide Astronomical Union created a definition for “planet” in 2006, Pluto misplaced full planet standing. Now astronomers are proposing a brand new definition of “planet.”
Deborah Byrd created the EarthSky radio sequence in 1991 and based EarthSky.org in 1994. Previous to that, she had labored for the College of Texas McDonald Observatory since 1976, and created and produced their Star Date radio sequence. In the present day, she serves as Editor-in-Chief of this web site. She has gained a galaxy of awards from the broadcasting and science communities, together with having an asteroid named 3505 Byrd in her honor. In 2020, she gained the Training Prize from the American Astronomical Society, the most important group {of professional} astronomers in North America. A science communicator and educator since 1976, Byrd believes in science as a drive for good on the earth and an important device for the twenty first century. “Being an EarthSky editor is like internet hosting a giant world social gathering for cool nature-lovers,” she says.
