Even though the cloud-shrouded Venus is often labeled as Earth's twin due to its similar size, gravity and "terrestrial" composition-primarily made up of silicate rocks or metals-this second-planet from the Sun is a hellish place.
Venus is cloaked in a thick layer of highly reflective clouds of sulfuric acid. It has the densest atmosphere of the four terrestrial planets, consisting mostly of carbon dioxide. The crushing atmospheric pressure at the planet's surface is 92 times that of Earth's. To top it off, Venus' surface temperature is hotter than an oven.
No wonder then, that investigating this wicked world gives pause to space exploration engineers.
But that's just the challenge being tackled by Geoffrey Landis of NASA's Glenn Research Center in Cleveland. And thanks to funding from the NASA Innovative Advanced Concepts (NIAC) program, he and his team are looking into the limits of technology in high-temperature electronics, robotics, and "Venus-hardened" systems.
Working with the Collaborative Modeling for Parametric Assessment of Space Systems (COMPASS) Laboratory at Glenn, Landis has set sail on a new type of spacecraft: the Venus Landsailing Rover, dubbed the Zephyr and taken from Aphrodite, the Greek goddess of love and beauty.
"The gentle winds carried Aphrodite across the sea, to Cythera and then to Cyprus, by the god of the west wind, Zephyrus," Landis explained.
"Compared to Mars, Venus has been a comparatively unexplored planet," Landis says, detailing his progress during the 2013 NIAC Spring Symposium, held last March in Chicago. "But Venus is phenomenally difficult to explore," he quickly adds.
One bit of good news: below the murky mess of an atmosphere on Venus, it's clear below around 18 miles high (30 kilometers).
You want to be able to rove across the surface, Landis says, using the ambient resources of Venus. "One approach is just live with the high temperatures by using high-temperature devices," Landis says, and in fact, the environment of Venus is no harsher than that within a revved up jet engine.
Actually, Glenn technologists have pioneered sensors that work inside jet engines. Those electronics can function even at the sweltering Venus temperature of 450 degrees Celsius, or 840 degrees Fahrenheit.
But one part of the Landis NIAC study is focused on using wind force on Venus as a propulsive nudge. While the winds at the surface of Venus are low (under one meter per second, or just a little over two miles per hour), at Venus pressure, even low wind speeds develop significant force, he explains.
"A sail rover would be extraordinary for Venus. The sail has only two moving parts-just to set the sail and set the steering position-and that doesn't require a lot of power. There's no power required to actually drive," says Landis.
Wind vehicles have been used on Earth for over a century, Landis adds, pointing to the Kansas wind wagons from the 1850s. Today, there's a thriving community of wind sailors that race across the Sahara desert, for example.
The tri-wheeled Venus Landsailing Rover-rising some seven meters or 22 feet above the Venus terrain-won't necessarily be a speedster scooting across the planet, Landis says. It will be a vehicle that mostly sits in one place, analyzing the ground, he notes, and every now and then will rove across Venus to a new spot.
"Most of Venus is remarkably flat," Landis observes. "It is as flat and rocky as a parking lot." The rover is designed to drive equally well forward or backward. That allows the vehicle to back off of obstructions.
Landis and his colleagues on the NIAC-funded study see their rover-replete with about 12 square meters of solar cell-laden sail-tooling across Venus for about a month, chalking up 15 minutes of sailing per day.
"So the fundamental elements of a rover for Venus are not beyond the bounds of physics," Landis observes, "we could survive the furnace of Venus if we can come up with an innovative concept for a rover that can move on extremely low power levels."
For Landis, the bottom line about his NIAC study: "Sailing on Venus! How cool is that?"