From possible planets to STRANGE NEW WORLDS

With 5,000 exoplanets now confirmed and another 5,000 waiting to follow suit, Ezzy Pearson takes a look at how a deluge of tantalising data is revealing intriguing new worlds every day

- Ezzy Pearson

Back in 1992, humanity received its first definitive answer to a question it had been asking for centuries: are there other worlds beyond our Solar System? The answer came in the form of Poltergeist and Phobetor, the first potential planets to have their existence confirmed and become fully fledged exoplanets.

Over the following three decades, dozens of surveys and observation campaigns have tracked down ever more exoplanets in the Milky Way, and on 21 March 2022 the NASA Exoplanet Archive announced it had passed the threshold of 5,000 validated exoplanets.

But while it took 30 years to reach this number, doubling it will take considerably less time. In the same month as the archive's announcement, astronomers working on NASA's Transiting Exoplanet Survey Satellite (TESS) revealed they had obtained another 5,000 exoplanet candidates, which were awaiting confirmation, and there were even more to come.

It's a huge number to keep track of. Back in the early days when there were only a few known exoplanets, astronomers would each have their own spreadsheets listing them. But as the dozens grew to hundreds and then thousands, it became apparent a dedicated system was needed, leading NASA to create the Exoplanet Archive.

"NASA keeps track of all the planets we've found outside our Solar System and anything we know about them," says Jessie Christiansen, the lead scientist for NASA's Exoplanet Archive at Caltech, who updates the archive. "It's a big database of everything that we know about exoplanets and the stars they orbit."

I would find 5,000 worlds...