Professor Alicia Sintes had just finished teaching a class at the University of the Balearic Islands on September 14th and was heading to lunch when she started getting urgent messages.
The international physics project she had been working with for more than a decade had detected something unusual through instruments in the United States. Soon she was getting a "tsunami of emails" alerting researchers about the detection.
"I was like 'what the hell is going on'," Sintes told The Local over the phone from her office in Palma de Mallorca.
From that point on, researchers around the world, including in Sintes' group, worked tirelessly to analyze data and understand what the instruments had found.
It was officially announced on Thursday that the instruments had picked up for the first time ever gravitational waves - ripples in the fabric of space and time produced by massive objects, first predicted by Einstein 100 years ago. This is an unprecedented discovery that even Einstein himself thought was not possible.
The instruments stationed in Louisiana and Washington were part of the Advanced Laser Interferometer Gravitational-wave Observatory (LIGO) project which involved 1,000 researchers in 15 different countries, including just one group in Spain under Sintes.
The gravitational waves detected came from two black holes merging together into a bigger black hole - 1.3 billion years ago.
The detectors in the US use an L-shape to send lasers to two different ends and then back to the centre. If one laser returns after the other one, it means a gravitational wave stretched space and time resulting in one laser taking longer than the other to get back.
The detection of these waves offers a new method for astrophysicists to study outer space. Previously, researchers had relied on methods involving light, but now Sintes said scientists can also use gravitational waves to find new objects.
"We now have a new way to observe the universe... we can listen to the universe," she explained.
When Einstein first wrote about gravitational waves in 1916, he believed they could never be detected because they were too faint.
“I don't think he would mind being wrong, I think he would be happy,” Sintes told The Local.
Sintes' group has worked to confirm data analysis from the detectors. Several members of the team also played a major role in the project, including a student who was in the control room in the Washington observatory when the waves were detected, and Sintes' husband at the Balearic Islands university who helped identify the merger of the black holes.
This discovery has been a long time coming for many like Sintes. The observatory took decades to build and cost $1.1 billion.
"I've spent 19 years of my life analyzing noisy data, and now we have something real, something not from Earth," Sintes said. "And then you are happy to see that finally we see something and we see it so clearly."
But the work is not over yet, Sintes said, and they have to continue to study more data picked up by the instruments to see if there are other signs of cosmic activity.
Could this finding win the multinational team the Nobel Prize?
"I think so," Sintes told The Local. "This is not just one event, more will come. Within the next five years, it will get the Nobel Prize."