Titan, one of Saturn’s 82 moons and so large it outsizes the planet Mercury, has strange characteristics which have baffled astronomers. In the late 2000s, experts using NASA‘s Cassini spacecraft spotted strange bright patches on the large celestial body which left scientists dumbfounded. However, a new study has revealed the bright spots are actually dried out lake beds.
The lakes were not water bodies as we know them, but lakes made up of hydrocarbon.
The results of the study confirm the theory that Titan is the only other celestial body that we know of which contains liquid bodies on its surface.
The study published in the journal Nature said: “Titan observations provide ground-truth in the search for oceans on exoearths and an important lesson is that identifying liquid surfaces by specular reflections requires a stringent definition of specular.”
However, the lakes and seas are concentrated near Titan’s poles, not the tropics as would be expected on any celestial body.
To solve the riddle, Jason Hofgartner, of NASA’s Jet Propulsion Laboratory in Pasadena, California and his colleagues revisited archive data.
After correcting discrepancies between the ways the various observations referred to locations on Titan, the team realised the reflections originated from a few specific spots.
The researchers considered whether rainfall, dunes or dry lake beds could be responsible for the reflections, and found that only lake beds explain the timing and locations of the signals.
Planetary scientist Zibi Turtle of Johns Hopkins University’s Applied Physics Laboratory who was not involved in the study, said: “I think it’s a compelling argument.
“It’s great to have an answer to this outstanding question and one more piece of Titan that we understand better now.”
NASA has long touted “unique” Titan as a possible home for alien life.
The space agency will send a helicopter-esque probe, dubbed Dragonfly, to Titan to be launched in 2026 and arrive in 2034 to scope out the moon and see if there is evidence of alien life.
The craft will hover the celestial body and occasionally drop down over five-kilometre sections to the surface to collect samples.
Previous discoveries from the space agency have found Titan is covered in a rich organic chemical which is similar, scientists believe, to the compounds which helped build life on Earth.
NASA has said: “NASA’s next destination in the solar system is the unique, richly organic world Titan.
“Advancing our search for the building blocks of life, the Dragonfly mission will fly multiple sorties to sample and examine sites around Saturn’s icy moon.
“Dragonfly marks the first time NASA will fly a multi-rotor vehicle for science on another planet; it has eight rotors and flies like a large drone.
“It will take advantage of Titan’s dense atmosphere – four times denser than Earth’s – to become the first vehicle ever to fly its entire science payload to new places for repeatable and targeted access to surface materials.
“Titan is an analogue to the very early Earth and can provide clues to how life may have arisen on our planet.
“During its 2.7-year baseline mission, Dragonfly will explore diverse environments from organic dunes to the floor of an impact crater where liquid water and complex organic materials key to life once existed together for possibly tens of thousands of years.
“Its instruments will study how far prebiotic chemistry may have progressed. They also will investigate the moon’s atmospheric and surface properties and its subsurface ocean and liquid reservoirs.
“Additionally, instruments will search for chemical evidence of past or extant life.”