Extreme exoplanets

The more we learn about exoplanets, the more we realise the universe is stranger than we ever imagined

The more we learn about exoplanets, the more we realise the universe is stranger than we ever imagined

It’s almost hard to believe that until the early years of the 1990s, astronomers had yet to discover a planet outside the Solar System. Even though scientists were certain that planets orbited other stars, there was little evidence of other planetary systems until the discovery of two extrasolar planets – or exoplanets – orbiting the pulsar PSR B1257+12 in 1992 by Aleksander Wolszczan and Dale Frail. This initial discovery was soon followed by the observation of 51 Pegasi b – the first exoplanet discovered around a Sun-like star – in 1995, for which astronomers Michel Mayor and Didier Queloz were awarded the 2019 Nobel Prize in Physics.

Since 1995 our exoplanet catalogue has rapidly expanded. We have now confirmed over 4,400 worlds outside our Solar System, with a further 7,600 or so suspects waiting to be classified. As our observation methods improve, this discovery process has only really just begun. And later this year, the James Webb Space Telescope (JWST) will finally launch, with part of its mission dedicated to searching for exoplanets.

A surprising factor has started to present itself as we learn more about worlds outside the Solar System: the universe is weird. Really weird. From worlds that rain iron and glass to diamond worlds and planets that have escaped the grip of their parent stars, our burgeoning exoplanet catalogue demonstrates that our own Solar System is reassuringly boring.