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Liquid methane ¹-filled canyons ² hundreds of meters deep with walls as steep as ski slopes etch the surface of Titan, researchers report in a new study. The new findings provide the first direct evidence of these features on Saturn ³'s largest moon, and could give scientists insights into Titan's origins and similar geologic ⁴ processes on Earth, according to the study's authors. New Cassini radar ⁵ observations of Titan's north pole depict ⁶ cavernous gorges ⁷ a little less than a kilome-ter (less than half a mile) wide with walls up to 570 meters (1870 feet) tall -- about 30 meters (98 feet) higher than New York's Freedom Tower. The eight canyons branch off from Vid Flumina, a more than 400-kilometer (249-mile) long river flowing into Titan's second-largest sea, Ligeia Mare ⁸. The new data confirm the canyons are filled with flowing methane -- a feature researchers had suspected but not directly observed, according to the study's authors. , ,The new findings suggest the canyons were likely carved by liquid methane draining into Vid Flumina, a process similar to the carving ⁹ of river gorges on Earth, according to the study's authors. The new re-search could help scientists better understand these geological processes, they said. , ,"These are processes we need to totally understand because they can shed deeper light on our own planet," said Valerio Poggiali, a planetary scientist at the La Sapienza University of Rome, Italy, and lead author of the new study published in Geophysical Research Letters, a journal of the American Geophysical Union., ,NASA's Cassini spacecraft, launched in 1997, has granted scientists their first up-close look at Saturn, its rings and moons. Cassini's observations of Titan -- with its many Earth-like features -- have given sci-entists a glimpse of what our planet might have been like millions of years ago, according to NASA.