The exoplanet known as Fomalhaut b or Dagon was discovered in 2008 in the constellation, Piscis Austrinus and was the first planet to be discovered outside of our solar system and it was just 25 light-years away. The planet was even documented through years of observation through NASA's Hubble Space Telescope.However, a more recent discovery reveals that the planet has disappeared, leading scientists to believe that it doesn't exist.Instead, researchers suspect that the planet was literally a cloud in disguise. The scientists believe the 'planet' was actually the result of two icy bodies crashing together, leaving a large cloud of dust in its wake. While the identification of the planet has been ruled out as a mistake, the observations allowed scientists to observe another rare phenomenon, a collision. Andras Gaspar, an assistant astronomer at the University of Arizona Steward Observatory has stated:These collisions are exceedingly rare and so this is a big deal that we actually get to see evidence of one, we believe that we were at the right place at the right time to have witnessed such an unlikely event with NASA's Hubble Space Telescope.Fomalhaut b Getty ImagesThe collision also gives researchers an insight as to how planets can collide and destroy each other. George Rieke, a Regents Professor of Astronomy at Steward Observatory noted:The Fomalhaut star system is the ultimate test lab for all of our ideas about how exoplanets and star systems evolveHe continued: "We do have evidence of such collisions in other systems, but none of this magnitude has been observed in our solar system. This is a blueprint of how planets destroy each other." The conclusion was drawn after researchers took a closer look at the characteristics of the exoplanet. Fomalhaut b emitted enough light to be seen, which was a clue in itself. Scientists have stated that an exoplanet would not emit enough light to be seen from Earth. Also, heat could not be spotted in infrared imaging. Where any planet to give off light like that would have had shown warmth.