An exoplanet disappeared from the Hubble observations, and the reason is something unexpected that we’ll detail below.
Back in 2004 and 2006, the Hubble Space Telescope managed to capture something incredible – a planet orbiting a star called Fomalhaut 25 light-years away.
This was directly detectable in visible light, and this was something really rare for exoplanets which are usually too small and faint to be seen.
The object was confirmed in 2012
Science Alert notes that “The object, formally named Fomalhaut b or Dagon, was announced in 2008, and confirmed in 2012, thought to be a gas giant on a 1,700-year, highly elliptical orbit around its host star.”
The same website continues and reports that while examining previously unpublished Hubble images that had been taken back in 2014, astronomers were shocked. “The putative planet hadn’t just changed. It wasn’t that its orbit was not as expected,” Science Alert notes.
In its place, there was nothing and this led astronomers to the conclusion that the spot was never an exoplanet at all.
A rare sight – the aftermath of a collision
On the other hand, they are now believing that the bright spot that is visible in the early Hubble images is a rare sight – the aftermath of a collision between two asteroid-sized planetesimals.
“These collisions are exceedingly rare and so this is a big deal that we actually get to see one,” said astronomer András Gáspár of the University of Arizona.
He continued and explained that “We believe that we were at the right place at the right time to have witnessed such an unlikely event with the Hubble Space Telescope.”
The same publication mentioned above notes that the identification of Dragon as an exoplanet was always surrounded by all kinds of issues.
We recommend that you head over to the original article in order to learn more details on the matter.