Titan's tidal mysteries: New insights from Cassini data revealed
Although the Cassini probe was destroyed in 2017, scientists continue to analyse the data it has collected. This has led to discovering another mystery of Titan, Saturn's largest moon. Researchers announce that "this is just the first step" and that more mysteries will soon come to light.
The NASA-owned Cassini-Huygens space probe completed its 20-year mission studying Saturn and its satellites seven years ago when it plunged into the gas giant's atmosphere. Despite this, it still provides a wealth of extraordinary scientific data. Using radar data from Cassini, astronomers from Cornell University gathered new information about Titan's oceans, which consist of hydrocarbons, mainly methane and ethane.
The team, which included Valerio Poggiali, a researcher at the Cornell Centre for Astrophysics and Planetary Science (CCAPS), managed to analyse the composition of the seas near Titan's north pole and examine their surface.
Scientists discovered gentle tidal currents in the calm methane seas, as indicated by the space.com portal. Earlier studies were unable to show this.
The Cassini probe collected the radar data Poggiali and his colleagues used during four flybys on 17 May, 18 June, and 24 October 2014, and again on 14 November 2016. The radar, equipped on the Cassini probe, recorded waves about 3 millimetres in diameter. Where the hydrocarbon seas met the shore, wave heights increased to just 5 millimetres. This indicates the existence of weak tidal currents.
"This is the first step." scientists continue to analyse data
Scientists analysed data from observations of Titan's three polar seas: Kraken Mare, Ligeia Mare, and Punga Mare. They discovered that the composition of the surface layers of the hydrocarbon seas depends on location and latitude. They also concluded that Titan might have a phenomenon similar to what we know from our planet.
We also have indications that the rivers feeding the seas are pure methane," Poggiali said, "until they flow into the open liquid seas, which are more ethane-rich. It’s like on Earth, when freshwater rivers flow into and mix with the salty water of the oceans — said Poggiali.
Poggiali added that the team continues to work with the data generated by the Cassini probe during its 13 years of studying Titan. There is a trove of data that still awaits full analysis, which should yield more discoveries. This is just the first step, he summarised.
The results of the team's research were published on Tuesday (16 July) in the journal "Nature Communications".
