Over 5,000 worlds beyond our solar system

Source: By Mint

The count of confirmed new worlds outside of our solar system just ticked beyond 5,000 with the discovery of 65 new exoplanets, confirmed by the National Aeronautics and Space Administration.

The latest contribution to the NASA Exoplanet Archive, which records exoplanet discoveries that appear in peer-reviewed, scientific papers, comes as NASA's $10 billion James Webb Space Telescope readies for planet-gazing operations in deep space.

It's not just a number," said Jessie Christiansen, science lead for the archive and a research scientist with the NASA Exoplanet Science Institute at the California Institute of Technology in Pasadena, in a statement. "Each one of them is a new world, a brand-new planet. I get excited about everyone because we don't know anything about them."

How were exoplanets discovered?

The discovery of exoplanets had begun in 1992 with strange new worlds orbiting an even stranger star. It was a type of neutron star known as a pulsar, a rapidly spinning stellar corpse that pulses with millisecond bursts of searing radiation.

Measuring slight changes in the timing of the pulses allowed scientists to reveal planets in orbit around the pulsar.

Finding just three planets around this spinning star essentially opened the floodgates, said Alexander Wolszczan, the lead author on the paper that, 30 years ago, unveiled the first planets to be confirmed outside our solar system.

“If you can find planets around a neutron star, planets have to be basically everywhere," Wolszczan said. “The planet production process has to be very robust." The Nancy Grace Roman Space Telescope, expected to launch in 2027, will make new exoplanet discoveries using a variety of methods.

The ESA (European Space Agency) mission ARIEL, launching in 2029, will observe exoplanet atmospheres; a piece of NASA technology aboard, called CASE, will help zero in on exoplanet clouds and hazes.

Varied features of exoplanets

The 5,000-plus planets found so far include small, rocky worlds like Earth, gas giants many times larger than Jupiter, and “hot Jupiters" in scorchingly close orbits around their stars.

There are “super-Earths," which are possible rocky worlds bigger than our own, and “mini-Neptunes," smaller versions of our system’s Neptune. They also include planets orbiting two stars at once and planets stubbornly orbiting the collapsed remnants of dead stars.

Are there aliens on any one of the exoplanets?

Astronomers believe that there is a possibility of finding something resembling life on any of these exoplanets. “To my thinking, it is inevitable that we’ll find some kind of life somewhere – most likely of some primitive kind," Wolszczan said.

The close connection between the chemistry of life on Earth and chemistry found throughout the universe, as well as the detection of widespread organic molecules, suggests detection of life itself is only a matter of time, he added.