Since the beginning of the space age, very few space crafts have landed on Venus, and none on Europa-an icy moon of Jupiter.
At the virtual American Geophysical Union meeting, planetary scientists and engineers discussed new tricks that hypothetical future spacecraft may need to land on unfamiliar terrain on Venus and Europa.
Venus is a very difficult world to visit. It’s high temperatures and crushing atmospheric pressures have led to the destruction of space crafts that managed to reach its surface two hours after their arrival.
In one of the proposed plans discussed at the AGU meeting, scientists plan on landing on a mountainous terrain on Venus called tessera.
“Safely landing in tessera terrain is absolutely necessary to satisfy our science objectives,” said planetary scientist Joshua Knicely of the University of Alaska Fairbanks in a talk recorded for the meeting. “We have to do it.”
Unfortunately, the best maps of the planet—from NASA’s Magellan orbiter in the 1990s—can’t tell engineers how steep the slopes are in tessera terrain.
“We have a very poor understanding of what the surface is like,” Gilmore said in a talk recorded for the meeting. “What’s the boulder size? What’s the rock size distribution? Is it fluffy?”
The biggest obstacle involves seeing the ground to land, as Venus’s dense atmosphere scatters lights and blind reflectors.
Europa, on the other hand, has no air to blur the surface or break rockets. A hypothetical future Europa lander, also discussed at the AGU meeting, would be able to use the “sky crane” technique.
“The engineers are very excited about not having to deal with an atmosphere on the way down,” said spacecraft engineer Jo Pitesky of NASA’s Jet Propulsion Laboratory in Pasadena, California in a recorded talk for the meeting.
Still, a lot is unknown about Europa’s surface.