Researchers in the US say they’ve created a fluid with negative mass in the lab… which is exactly as mind-bending as it sounds.

What it means is that, unlike pretty much every other known physical object, when you push this fluid, it accelerates backwards instead of moving forwards. Such an oddity could tell scientists about some of the strange behaviour that happens within black holes and neutron stars.

But let’s take a step back for a second here, because how can something have negative mass?

Once upon a time, two black holes collided, releasing energy which undulates across the universe. Little is known about these reverberations — dubbed “gravitational waves” — including how they were formed in the first place. However, a University of Birmingham astrophysicist told Sputnik science may now have the beginnings of an answer.

It’s believed that around 1.3 billion light years away from Earth, two black holes cataclysmically collided, releasing energy — gravitational waves — which undulates across the universe like ripples in a pool.

Gravitational waves had long been speculated upon, and were a major prediction of Albert Einstein’s 1915 general theory of relativity, but the existence of these wrinkles in the fabric of space-time was only confirmed in September 2015.

Using eight telescopes scattered across the globe, astronomers will collect data at a scale never attempted before in physics as they attempt to peer into a black hole for the first time. Event Horizon Telescope.

Meanwhile, the Hubble image offered a clue about what dislodged the black hole from its galaxy’s centre. The host galaxy bore faint, arc-shaped features called tidal tales, which are produced by the gravitational tug-of-war that takes place when two galaxies collide. This suggested that galaxy 3C 186 had recently merged with another system, and perhaps their black holes merged too.

What happened next, scientists can only theorize. Chiaberge and his colleagues suggest that as the galaxies collided, their black holes began to circle each other, flinging out gravity waves “like water from a lawn sprinkler,” as NASA described it. If the black holes had unequal masses and spin rates, they might have sent more gravitational waves in one direction than the other. When the collision was complete, the newly merged black hole would have then recoiled from the strongest gravitational waves, shooting off in the opposite direction.

“This asymmetry depends on properties such as the mass and the relative orientation of the back holes’ rotation axes before the merger,” Colin Norman of STScI and Johns Hopkins University, a co-author on the paper, said in the NASA news release. “That’s why these objects are so rare.”

Astronomers have uncovered a supermassive black hole that has been propelled out of the center of a distant galaxy by what could be the awesome power of gravitational waves.

Though there have been several other suspected, similarly booted black holes elsewhere, none has been confirmed so far. Astronomers think this object, detected by NASA’s Hubble Space Telescope, is a very strong case. Weighing more than 1 billion suns, the rogue black hole is the most massive black hole ever detected to have been kicked out of its central home.

Researchers estimate that it took the equivalent energy of 100 million supernovas exploding simultaneously to jettison the black hole. The most plausible explanation for this propulsive energy is that the monster object was given a kick by gravitational waves unleashed by the merger of two hefty black holes at the center of the host galaxy.