Ever since the Huygens probe descended through the atmosphere of Saturn’s moon Titan in 2005, planetary scientists have dreamed of extended missions to the bizarre planet. With an active surface, lakes of liquid methane, and a thick atmosphere, Titan promises scientific riches—especially to a craft designed to linger, and to cover distances. The prospects open to a flying craft, as opposed to stationary landers or even rovers, is tantalizing.
Graham Dorrington of the University of London has gathered a striking host of possibilities in a survey article in the journal Advances in Space Research—including several versions of such lighter-than-air craft as balloons and dirigibles. The concepts include airships filled with hydrogen, argon, and heated methane; balloons that carry wind turbines to furnish power to onboard instruments; and high-altitude craft that dangle instrument packages on tethers seven miles long to reach below the haze layer obscuring Titan’s surface. According to Mike Wall at Space.com, Dorrington estimates that such a craft could circumnavigate Titan in about 16 days. Given the daunting challenges balloon circumnavigators face on Earth, however, any mission in Titan’s uncertain environment would be daunting at best.
If a balloon ever does go to Titan, it would not be the first operated in another planet’s atmosphere. The Vega 1 balloon, a joint effort of France and the Soviet Union, cruised more than eleven thousand kilometers in Venus’ heavy, cloud-laden atmosphere in June of 1985. Compared to heavier-than-air craft such as jets, copters, or more exotic craft, balloon-like craft might prove a relatively inexpensive and technologically manageable way to survey the planet. And given the recent enthusiasm for sophisticated, DIY balloon trips to the upper atmosphere here on Earth, an extended ballooning expedition to Titan seems like an enticing prospect.[via Space.com]