Scientists may be at the beginning of a journey to discover that we aren’t alone in the universe. Whilst you’re unlikely to see an Extra Terrestrial riding a bicycle across the sky with the moon lighting the background any time soon (E.T. mention there in case it’s been missed), hear us out for a couple of minutes!
In May, scientists discovered two planets which orbit the dwarf star Trappist-1 and what is more, they are in the star’s ‘habitable zone’ (meaning it’s not too hot and not too cold – basically just how Goldilocks would like it!), which indicates that life may be out there after all.
Located 40 lightyears away from Earth (we’re afraid it’s not going to be a tourist spot), both planets are rocky like ours, which increases the chances of the planets having conditions that can sustain life. After being discovered, scientists had a race against time to write a research proposal and have it reviewed and accepted as a rare event was just two weeks away.
Luckily, they did it in time and were able to see a rare double transit as both planets passed nearly in tandem in front of their star. At the same time, the Hubble space telescope was in the right position in its orbit to view the planets.
The light from Trappist-1 dipped and flickered through the atmosphere of each planet. Large dips in light indicates an atmosphere of light glass with huge clouds high above the planet. A wavelength that only slightly varied indicates a denser, more compact atmosphere like our own (we know you’re getting excited now!).
Scientists discovered that there was little variation, which suggests it is most likely a terrestrial planet (meaning there is the potential for life). The double transit ruled out an atmosphere dominated by hydrogen, but there are still other options that need to be explored. There could be a water world, an atmosphere like Venus, one like Earth, or an atmosphere like Mars.
Further studies will be conducted on the Trappist-1 star and its orbiting planets, as well as 69 other stars. So will E.T. be phoning us any time soon? Probably not; we’re unsure of their broadband speeds at this point, but we’re a step closer to finding out.