Titan . ... Hubble Space Telescope Images of Titan's surface . ... Later that year, it will release the European-built Huygens probe for a descent through Titan's atmosphere. ... This artist's rendering shows the European Space Agency's Huygens probe descending into the atmosphere of Saturn's moon Titan after being released by NASA's Cassini spacecraft. ... This artist's rendering shows the Huygens probe on the surface of Saturn's moon Titan after being released by NASA's Cassini spacecraft. ...