La Palma telescope observes the collisions of dead suns

The Gravitational-wave Optical Transient Observer (GOTO), led by the University of Warwick and built in Spain's La Palma island, is expected to bring forth a new era of gravitational wave (GW) science.

The GOTO project consists of multiple wide-field telescopes on a single mount, which allows it to map large source regions in the sky to detect gravitational waves, and learn about their cause: the collisions of dead suns, scientifically known as neutron stars.

The crashes between these types of stars are thought to be the origin of most of the heavy metals in the universe including gold and platinum, billions of years ago. With the new addition to the telescope, scientists are expected to be able to witness this process and observe stars "being smashed together and observe the rich material that comes out of this explosion," said Professor Danny Steeghs, of Warwick University.

The neutron stars are made from a substance that is so heavy that a small teaspoon weighs four billion tonnes. Their immense weight causes the collapse of the stars themselves, crushing the atoms that once made them shine. Due to the strong pull of gravity, the neutrons are drawn to one another, until they eventually crash and merge. 

The force with which the stars collide is so large that it creates strong shockwaves that ripple across the universe, distorting space. These are known as gravitational waves. 

The light from these collisions is only visible for a couple of days in the night sky, so identifying it requires great skill and innovative technologies. 

The telescope is formed of two jet-black batteries of eight cylindrical telescopes bolted together, each of which covers every patch of sky above it by rapidly rotating vertically and horizontally.

"When a really good detection comes along, it's all hands on deck to make the most of it," Steeghs told the BBC. "Speed is of the essence. We are looking for something very short-lived - there's not much time before they fade away".

The GOTO scientists want to be able to locate the flashes in the sky within hours, or even minutes of detecting the gravitational wave. The researchers take photographs of the sky and then digitally remove the stars, planets and galaxies that were there the previous night to identify the neutron stars. 

This normally takes days and weeks, but GOTO can do it in real time.

"You would think that these explosions are very energetic, very luminous, it should be easy - but we are having to search through a hundred million stars for the one object that we are interested in. We have to do this very rapidly because the object will disappear within two days," said Dr Joe Lyman, another of the mission's scientists.

Once the astronomers pinpoint the collision, they turn to larger, more powerful telescopes across the world. These probe the collision in much greater detail, and at different wavelengths.

This process is "telling us about physics at the extreme," Dr Lyman explained.

GOTO has received £3.2 million of funding from the Science and Technology Facilities Council (STFC) to deploy the full-scale facility. The plan is to eventually create two twin telescopes, on opposite sides of the planet, to better track down the sources of gravitational waves.