This swarm of 66 radio telescopes gathers clues about the past and future of our Universe. Read more: Astronomers spot two stars colliding, creating stellar 'fireworks' 1,500 light years away
Lying 5,000 metres above sea level on Chile's Chajnantor Plateau, the Atacama Large Millimeter Array (Alma), detects some of the weakest signals emanating from the colder regions of the cosmos - the places stars no longer shine.
An international project jointly run by institutes in Europe, the US, Asia and Chile, Alma is "the most powerful telescope for studying the cool Universe", says Robert Laing, at the European Southern Observatory, which supports the project. “Unlike optical telescopes, which can see hot things like stars that give off mostly visible light, ALMA observes millimetre or sub-millimetre radiation that comes from objects at lower temperatures” — such as cool gas and dust clouds, or long-gone galaxies.
Alma is currently observing L2 Puppis, a declining red giant star that looks how our Sun might in five billion years – and suggests how Earth might be affected as its closest star cools. “Astronomers using ALMA have observed an object close to [L2 Puppis] that is probably a big planet. That’s interesting as it may be an indication that planets can survive the transition of their star to a red giant,” Laing explains.
In 2017, ALMA will study the presence of stellar winds around L2 Puppis, to see how they affect that nearby planet — a proxy for what could one day happen to Earth, says Pierre Kervella, an astronomer at the University of Chile and a lead scientist with ALMA. If dense winds are present, this could ultimately “lead to an inward migration of the planet, and its engulfment by the star,” he explains. As Laing puts it: “It’s a glimpse into the future of our solar system.”
This article was originally published by WIRED UK
