A part of Saturn's Moon Titan has appeared to be changing for years, and while scientists still aren't sure what the cause is, they have some interesting hypotheses.



The mystery began in 2013 when NASA's spacecraft Cassini captured a glimmer on the surface of methane and ethane lake known as Ligeia Mare.



According to the space agency, the bright spot was not present in 2007, appeared in a different form in 2014, and seems to have vanished again early last year.



Jason Hofgartner with NASA's Jet Propulsion Laboratory hypothesizes that the activity could be icebergs, bubbles, or even waves.



As he told New Scientist, "If it is waves, it could be because of the change of seasons."



He also added that the moon could be heading into summer which would likely mean stronger winds.



Cassini's last flyby of Titan next year could provide additional insight into this mystery.

See more of Saturn and its moons:



0 PHOTOS Saturn and moons See Gallery Could mysterious glimmer on Saturn's moon Titan be waves? Up Next See Gallery Discover More Like This HIDE CAPTION SHOW CAPTION of SEE ALL BACK TO SLIDE

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