Mars now draws a lot of interest from people on Earth, but Venus has recently been gaining more attention as a result of plans by NASA, the European Space Agency (ESA), and the New Zealand spaceflight company Rocket Lab to send missions there in the upcoming years.
In addition to this, NASA is considering sailing a robotic “aerobot” balloon in the Venusian winds to study the hostile planet.
NASA’s Jet Propulsion Laboratory (JPL) finally completed two test flights of an aerobot prototype over Nevada’s Black Rock desert as part of a study for a potential mission, successfully showing controlled altitude flights.
It is challenging to send a spaceship to Venus because of the planet’s strong heat, high pressure, and corrosive chemicals, which would render it worthless in a matter of hours. But a location where an aerobot could move safely is a few dozen miles above the hostile region.
“One concept envisions pairing a balloon with a Venus orbiter, the two working in tandem to study Earth’s sister planet,” JPL explains on its website. While the orbiter would remain far above the atmosphere, taking science measurements and serving as a communication relay, an aerial robotic balloon, or aerobot, about 40 feet (12 meters) in diameter, would travel into it, JPL continues.
The prototype balloon has an outer balloon made of helium that can expand and contract and an inside reservoir that is rigid and filled with helium. By changing the buoyancy levels and allowing helium to travel between the inner and outer sections, helium vents allow researchers to adjust the aerobot’s altitude.
Two flights were conducted to test a prototype balloon that was approximately one-third the size of the one that would travel to Venus in order to test the design. These flights were conducted by scientists and engineers from JPL and the Near Space Corporation, a commercial provider of high-altitude near-space platforms.
According to JPL, the balloon went 4,000 feet (1 km) to an area of Earth’s atmosphere with a density similar to what the aerobot would experience at a height of around 180,000 feet (55 km) above Venus.
JPL reported that the balloon traveled 4,000 feet (1 km) to a location in Earth’s atmosphere that is comparable to the density the aerobot would face at roughly 180,000 feet (55 km) above Venus.
The aerobot could float high above Venus for weeks or even months, according to the results of the Nevada tests. During this time, it could, among other things, monitor the atmosphere for venusquake-induced acoustic waves and analyze the chemical makeup of the planet’s clouds. All of the data collected would then be transmitted back to Earth via the accompanying orbiter.
JPL robotics technologist Jacob Izraelevitz said that they are extremely happy with the performance of the prototype. “It was launched, demonstrated controlled-altitude maneuvers, and was recovered in good condition after both flights,” added Izraelevitz.
Izraelevitz also said that they’ve recorded a mountain of data from these flights and are looking forward to using it to improve our simulation models before exploring our sister planet.
Since the Soviet Union used a similar design to study Venus in 1985 as part of its twin Vega 1 and 2 missions, balloons have been considered a practical means of doing so. Before their instrument batteries ran out, the two helium-filled balloons flew in the Venusian winds for just over 46 hours. JPL further stated that their short time in the Venusian atmosphere provided a tantalizing hint of the science that could be achieved by a larger, longer-duration balloon platform floating within the planet’s atmosphere.