NASA confirms the existence of 5,000 planets outside the solar system

(CNN) – According to NASA, there are now more than 5,000 confirmed planets outside our solar system.

The latest addition of 65 exoplanets to NASA’s Exoplanet Archive contributed to Monday’s landmark science achievement.
This archive includes exoplanet discoveries from peer-reviewed scientific articles that have been confirmed by multiple planetary discovery methods.

“It’s not just a number,” Jesse Christiansen, chief science officer for the archives and a researcher at the NASA Institute for Exoplanet Science at the California Institute of Technology in Pasadena, said in a statement. “Each one of them is a new world, a whole new planet. I’m excited for each one because we don’t know anything about them.”

We are currently living in a golden age of exoplanet discovery. Although the existence of planets outside our solar system has been previously suggested and certainly portrayed in science fiction, these worlds were not discovered until the 1990s.

Exoplanets have various properties

The diversity of exoplanets represents groups of planets unlike anything found in our solar system. Among them are rocky worlds larger than Earth, called super-Earths, sub-Neptune worlds larger than Earth but smaller than Neptune, and scorching, scorching Jupiters that dwarf the largest planet in our solar system and orbit closely around their host stars.

Scientists have also found planets orbiting more than one star, and some even orbiting the remains of dead stars called white dwarfs.

To date, 30% of confirmed exoplanets are gas giants, 31% are super-Earths, and 35% are Neptune-like. Only 4% of planets are terrestrial or rocky, such as Earth or Mars.

Previous discoveries of exoplanets were made thanks to telescopes and planet-hunting satellites, such as Spitzer Space TelescopeThe kepler space telescope and the Transit satellite to survey the outer planets.

When Christiansen was a graduate student in the early 2000s, only about 100 exoplanets are known.

“That’s part of the reason why I wanted to get into this field, because it was something very new and exciting about having planets around other stars,” Christiansen said in an interview. A joint question and answer session by Caltech. “Now, exoplanets are almost normal.

My colleague David Ciardi (chief scientist at NASA’s Exoplanet Archives) notes that half of the people alive have never lived in a world where we don’t know about exoplanets.”

Christiansen said Kepler has helped scientists discover about two-thirds of the 5,000 confirmed planets.

In the new batch of 65 planets, many are giant planets and sub-Neptunes, along with some hot Jupiter-sized planets.

There are also two Earth-sized planets, Christiansen said, but they are about 620 degrees Fahrenheit (327 degrees Celsius), so they are more “hot rocks” than the habitable planets.

He also noted that one of them is a system with five planets orbiting a small, cool red dwarf star, not unlike the TRAPPIST-1 system, where a similar star hosts seven rocky planets.

Space observatories join the hunt

New telescopes will only increase the probability of discovering exoplanets. The James Webb Space Telescope, launched in December, will be able to observe Atmospheres of the outer planets.

The Webb Telescope has been tuned to study the TRAPPIST system in detail.

The Nancy Grace Roman Space Telescope It will be launched in 2027 and will help in the search for exoplanets using various technologies. The European Space Agency’s ARIEL mission, scheduled to launch in 2029, will study the atmospheres of exoplanets.

Although scientists have confirmed the existence of more than 5,000 exoplanets, there are likely hundreds of billions of them in the entire Milky Way.

“Of the 5,000 known exoplanets, 4,900 are a few thousand light-years away from us. And let’s think we’re 30,000 light-years away from the galactic center; if we settle out of the little bubble around us, that means there are many more planets in the galaxy,” Christiansen said. Our galaxy, which we haven’t found yet, is 100 or 200 billion. It’s amazing.”