Scientists say they have proven the existence of gravitational waves — the ripples in space-time that stem from objects moving throughout the universe. If true, it’s the first time these waves have been measured directly and marks one of the biggest scientific discoveries in decades. But there have been a few false alarms before.
The discovery was made by the large group of researchers who make up the Laser Interferometer Gravitational-Wave Observatory (LIGO) Scientific Collaboration. The LIGO observatories picked up the wave signals on September 14th, 2015, coming from two distant black holes merging 1.3 billion years ago. The black holes spun around each other several times per second before merging in a massive explosion — a process that generates huge gravitational waves. These waves peter out on the way to Earth, requiring delicate instrumentation that must adjust for any interference on our planet. Though LIGO’s observations are ground-breaking, other scientists will need to pore over the data to make sure it’s correct.
Gravitational waves were predicted by Albert Einstein in 1918, as part of his theory of general relativity. Finding them would confirm a big part of that theory — and would also be the first step toward a new way of observing the cosmos.
This article originally appeared on Recode.net.