Is it time for NASA to pay more attention to Venus?
One of the more exciting news items recently in space science has been the discovery of phosphine gas in Venus’ atmosphere. The discovery has NASA and academic astrobiologists excited because the only known way phosphine is produced in nature is from microbes. In other words, scientists have found a signature for extraterrestrial life in one of the most unlikely locations in the Solar System, aside from Earth.
Forget Mars or the subsurface oceans of ice-bound Europa. The cloud-shrouded second rock from the sun may contain the holy grail of life that evolved on another planet.
Venus is thought to have started with an Earth-like environment billions of years ago. However, a runaway greenhouse effect appears to have turned its surface into a hellscape where the temperature is 900 degrees Fahrenheit, and the atmospheric pressure is 90 times that of the Earth’s surface. Clouds consisting of carbon dioxide and sulfuric acid prevail. The surface of Venus is pock-marked by craters and volcanoes.
However, Venus is different just 50 kilometers above the surface. While the surface of Venus is a veritable hellscape, the environment pf Venus’s upper atmosphere is relatively comfortable. The temperature, atmospheric pressure, and even radiation levels are as similar to that of the Earth surface as any place in the solar system.
Thus, the idea that microbes float in water droplets suspended in the Venusian atmosphere is entirely plausible. The question arises, when and how are we going to go and find out for sure?
Space.com reports that Rocket Lab has been retained to fly a private probe that would enter Venus’ clouds in 2023. It would search for signs of life during the brief period the probe passes through the “habitable zone” of Venus.
NASA Administrator Jim Bridenstine notes that two candidates for the next Discovery-class mission would head for Venus, one to examine the planet’s atmosphere, the other its geology. The space agency is involved in a proposed joint mission called Envision with the European Space Agency that would orbit Venus, mapping its surface.
NASA has been studying the possibility of deploying airships in Venus’ atmosphere. The first would likely be an uncrewed flagship-class mission that would ride the winds of Venus with instruments which, among other things, would search for life in the planet’s upper atmosphere.
The airship concept could even be expanded to a crewed mission. IEEE Spectrum explains how such a mission would work.
“The defining feature of these missions is the vehicle that will be doing the atmospheric exploring: a helium-filled, solar-powered airship. The robotic version would be 31 meters long (about half the size of the Goodyear blimp), while the crewed version would be nearly 130 meters long, or twice the size of a Boeing 747. The top of the airship would be covered with more than 1,000 square meters of solar panels, with a gondola slung underneath for instruments and, in the crewed version, a small habitat and the ascent vehicle that the astronauts would use to return to Venus’s orbit, and home.”
Getting such an airship safely into the upper atmosphere of Venus would be quite a challenge. Getting the astronauts safely home would be another. The mission would be not require anything like extravehicular activity. The astronauts would stay in the habitat, performing experiments, taking and analyzing samples.
Mars has been the focal point of human exploration dreams for decades, Indeed, the ultimate goal of Project Artemis, after the base is established at the lunar south pole, is a humans-to-Mars expedition, Popular culture, including the hit film The Martian and the current Netflix series Away have depicted those first voyages to the Red Planet. Elon Musk, the visionary CEO of SpaceX, dreams of founding a settlement on Mars. Scientists dream of discovering microbial life on the Red Planet, leftover, perhaps, from the era billions of years ago when Mars was Earth-like as well. Mars Perseverance is designed to ferret out such life.
Still, humankind may have been played a cosmic joke, by nature or God, in that the first signs that life evolved in another place besides Earth have been found in the winds of Venus, high above the land ravaged by heat and atmospheric pressure. The study of such life, if it exists, and how it may have survived the destruction of Venus’ original environment would be a boon to science that would be beyond evaluation.
Mark Whittington, who writes frequently about space and politics, has published a political study of space exploration entitled Why is It So Hard to Go Back to the Moon? as well as The Moon, Mars and Beyond. He blogs at Curmudgeons Corner. He is published in the Wall Street Journal, Forbes, The Hill, USA Today, the LA Times, and the Washington Post, among other venues.
