Does Anybody Care About Venus Anymore?
There’s a planet right down the street that could answer many questions about the origin of life.
No, not Mars.
The world I’m referring to is Venus. But despite all of its allure, Venus is one of the most challenging areas of the solar system for us to understand. Venus is superbly hellish, with temperatures warm enough to melt lead and an atmosphere featuring thick clouds of gaseous sulfuric acid.
NASA Isn’t Going For It
In 2017, five Venus mission proposals — such as a mapping orbiter, a stunt which would taste the air while falling, and landers that could zap stones with lasers — were all rejected by NASA. However, all were believed to be technologically ready to proceed.
“NASA’s mission selection process is extremely competitive,” According to Thomas Zurbuchen, associate administrator for NASA’s science mission applications in Washington, D.C. “Earth’s “twin” planet Venus is a fascinating body, and of tremendous interest to our science community.”
From afar, Venus and Earth would both seem like promising aims in the hunt for alien life. Both are approximately the same mass and size, and Venus lies near the sun’s habitable zone, where temperatures would allow liquid water to exist on the planet’s surface.
Only a handful of orbiters have seen Venus in the last ten years, including the European Space Agency’s Venus Express from 2006 to 2014, and the Japanese space agency’s Akatsuki, in orbit as of December 2015. But, despite heaps of suggested missions spanning nearly thirty decades, no NASA spacecraft has seen Earth’s twin because the Magellan craft finished its mission in 1994 by diving into Venus’ atmosphere and burning up. And nothing has landed there since 1985.
Venus Isn’t the Easiest Planet to Get Along With
One obvious barrier is Venus’ thick atmosphere that, in recent pictures taken by Akatsuki, makes the world seem like a smooth, milky marble. The air is 96.5 percent carbon dioxide, which blocks scientists’ view of this surface in just about all wavelengths of the light. As recently as 2011, astronomers thought it was impossible to make use of spectroscopy, a method that divides the light from an object into various wavelengths to figure out an object’s composition.
Nonetheless, it ends up that Venus’ atmosphere is transparent to five wavelengths of light which may help identify unique minerals. Venus Express proved it was possible. Appearing at a single infrared wavelength enabled astronomers to find hot areas which may be indications of active volcanism. They say an orbiter working with another four wavelengths could do much more
The atmosphere is one thing, but if we want to know what the surface is like, there is no getting around the fact that we need to go there. However, a lander would need to contend with all the thick atmosphere while searching for a safe spot to plop down. The best map of Venus’ surface, according to radar data obtained by Magellan, is at too low of a resolution to reveal slopes or rocks which may spell disaster for any craft that we try to land.
Scientists have been investigating a computer-vision technique known as Structure from Motion that may assist a lander with mapping on its decent. Quickly analyzing many pictures of static objects taken from various angles as the spacecraft descends may produce a 3-D representation of the floor.
A test in a helicopter above a quarry in Maryland revealed that the technology was capable of plotting boulders less than half of a meter across, or about the size of a typical microwave oven.
After a lander has made it to the surface, we won’t be celebrating quite yet, because mission success is still not a guarantee.
The very first landers on Venus, the Soviet Venera spacecraft from the 1970s and ’80s, lasted about an hour apiece. The record set by Venera 13 in 1982 had been just two hours and seven minutes. The world’s surface is roughly 460° Celsius, and the pressure is about 90 times that of Earth’s at sea level. Therefore spacecraft do not have long until some vital part melts, is crushed or becomes corroded by the polluted air. With as much as these things cost, we aren’t getting any bang for our buck.
Modern missions aren’t expected to perform much better. We could probably make it about five hours with current technology. Twenty-four would be a miracle.
NASA Hasn’t Completely Lost Interest
Thankfully, there may be some progress in the longevity department. A group at NASA’s Glenn Research Center in Cleveland is designing a lander that could last months. So, apparently NASA still has some hope left for Venus Exploration. It just needs to be cost effective in order to be plausible.
In the end, the team wishes to construct a prototype lander that may persist for 60 days. On Venus, that will be long enough to work as a weather station, tracking changes in the air over time and in the process learning a great deal about it, something that we haven’t achieved yet.
There is hope on the horizon, but only if Venus explorers can shrink their aspirations. This past year, NASA launched a program named Venus Bridge to determine whether any potential missions to Venus would be able to fly for $200 million or less. This amount is about half, or even less than half all of the proposed missions so far.
So, while the future for Venus research seems somewhat held back, at least some advancements and progress are being made in this area. But for now, it seems we have put it on the back burner for the time being. Currently, it’s just too problematic to be cost-effective.
