There are strange hazy streaks on Pluto's atmosphere and NASA has recently discovered what's been causing these. NASA's New Horizons probe has captured the said layers that looked like water ripples.

However, different from what scientists first assumed that this phenomenon is caused by gravitational waves, NASA said that these layers are due to buoyance waves or gravity waves, as per Tech Times.

What's the difference between gravity and gravitational waves, you say? Confusing as it may seem, these two waves are, in fact, different. Gravitational waves are the result of the collision of two black holes 1.3 million years ago. The Laser Interferometer Gravitational-Wave Observatory (LIGO) confirmed the existence of gravitational waves last February when they finally reached Earth.

Meanwhile, according to Alan Stern, principal investigator for New Horizons, gravity waves in Pluto appear due to the interaction of one fluid from another, as per Space.com.

New Horizons team member Darrel Strobel theorizes that because certain elements go to "sudden changes" and act differently on Pluto and Earth (e.g, sublimation or ice going into a gaseous state without melting into liquid), it creates a force that results to the hazy streaks or ripples on Pluto's surface. Imagine a rock hitting a surface of a lake, creating water ripples -- that's how gravity waves work.

Stern said, "[These are] not cosmological gravity waves, but atmospheric buoyancy waves. There's now a growing consensus on our team that the structures you see, that horizontal banding or layering, is formed by gravity waves."

Strobel added that the forces present on Pluto's atmosphere are not static and balance. This imbalance and difference in pressure and topography can push winds to create gravity waves.

Since New Horizon's arrival in Pluto in 2015, the dwarf planet has surprised NASA scientists with astonishing and perplexing discoveries because they thought that Pluto had no surface. Recent spottings on Pluto include a giant icy "spider" and some strange halo craters made up of pure methane.