Landmark: NASA approves 5,000 planets outside the solar system

Given hundreds of billions of planets for the Milky Way alone, “inevitably some kind of life is found somewhere”

What do planets look like outside our solar system? A variety of options are shown in this figure. Scientists discovered the first planets in the 1990s. As of 2022, the number stands at just over 5,000 happy planets. Credit: NASA / JPL-Caltech

The number of approved exoplanets has just passed the 5,000 milestone, after a thirty-year discovery mission led by NASA space telescopes.

Until recently, we lived in a universe where only a small number of planets were known, all orbiting the sun. But numerous new discoveries mark a scientific record: there are now more than 5,000 planets whose existence has been confirmed beyond our solar system.

The planet count exceeded 5,000 on March 21, with the last cluster of 65 planets added to the extrasolar NASA solar system archive. Discovery or using analytical techniques.

The 5,000 and more planets found so far include small, rocky worlds like Earth, gaseous giants several times larger than Jupiter and many “hot Jupiter” planets orbiting their planet in hot close orbits. There are “super-Earths”, which are the largest possible rocky worlds from our world, and “Neptune species”, smaller versions of Neptune in our solar system. And add to the mix planets orbiting two stars simultaneously and planets stubbornly orbiting the remains of collapsed dead stars.

To date, astronomers have confirmed more than 5,000 planets. It’s just a small fraction of the hundreds of billions that probably exist in our galaxy. The cones of the discovery of exoplanets emerge from the planet Earth, like spokes on a wheel. Many more discoveries await. Credit: NASA / JPL-Caltech

“It’s not just a number,” said Jesse Christiansen, the archive’s scientific director and research scientist at the Institute of Planetary Sciences outside NASA’s solar system at Caltech in Pasadena. I’m excited about each one because we know nothing about them. “

We know this: our galaxy probably has hundreds of billions of such planets. The ongoing stream of discoveries began in 1992 with new and strange worlds surrounding an even more bizarre star. It was a type of neutron star called a pulsar, a stellar corpse that spins rapidly and pulsates with powerful radiation bursts of milliseconds. Measuring small timing changes in pulses allowed scientists to discover planets orbiting the pulsar.

There were only three planets orbiting this spinning star and then the flood began, said Alexander Wolschen, the lead author of the article that 30 years ago revealed the first planets approved outside our solar system.

“If planets can be found around a neutron star, then planets must be almost everywhere,” Walschen said. “The process of creating planets has to be very powerful.”

The 5,000-plus planets approved in our galaxy include a variety of types, including a mysterious type known as the “Super Earth” because these planets are larger than our world and possibly rocky. Credit: NASA / JPL-Caltech

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