The surface of Venus has one of the most fearsome environments in the Solar System that is literally unapproachable and yet spacecraft have attempted to land on it, but the hardiest have survived barely two hours. Photos of the surface show a rock-strewn, barren desert bathed in an eerie yellow-orange light that would entice anyone to simply take an evening stroll, but it lends no clue to the horror the planet truly is.

The atmospheric pressure at the surface is nearly 90 times Earth’s, or 1320 pounds per square inch compared to 16 pounds on Earth. This is as much pressure as at 3000 feet under the ocean. The average surface temperature is 870ºF, hot enough to melt lead, tin, and zinc. A metallic frost of lead and bismuth compounds coat the mountain peaks where it hovers at a chilly 700ºF. It also rains sulfuric acid, but it is so hot that it evaporates before reaching the surface. The air is an unbreathable toxic mixture of mainly carbon dioxide with traces of nitrogen and other compounds. The air almost behaves like a fluid closely resembling dry cleaning fluid. Venus is a life-destroying planet, but there is one part of Venus far removed from the burning rocks that is not so bad. The cloud layer is a zone that is almost Earthlike with a more pleasant temperature and pressure, save for the sulfuric acid. Is there a possibility that life could exist there?

A team of scientists announced the discovery of phosphine in the atmosphere of Venus in 2020. This molecule is frequently made on Earth by microbes. The confidence in its discovery has waned since phosphine can be made from powerful volcanic eruptions which may be happening on Venus today. Even though the excitement has faded, the possible existence of phosphine has inspired an international group of scientists and the California-based company Rocket Lab to team up and send their very own spacecraft to plunge through the clouds of Venus. The mission is known as Venus Life Finder, the first mission in the Morning Star Venus exploration program. It may launch as soon as next year descending through the clouds not looking for phosphine but instead searching for the glow of organic compounds using a laser.

The probe will have only 30 minutes to perform its tasks before the increasing heat and pressure beneath the cloud deck destroys it. If it succeeds in detecting organic chemistry occurring in the clouds that is necessary for biology, but not proof of life, it will change our thinking about Venus and of life in general. Two things would happen. First, private companies will be inspired to send relatively inexpensive, focused spacecraft to worlds as extreme as Venus. If Rocket Lab succeeds with this $10 million mission, which costs 1/20 to 1/100 the cost of typical science missions, a new era of planetary exploration will ensue. Second, there will be a redefining of what it means for a world to be potentially habitable.

Around several hundred million to possibly a billion years ago something went terribly wrong with Venus. It may have had an ocean beneath a blue sky with scattered puffy white clouds and was very toasty, but with a survivable climate. Then a possible series of gargantuan volcanic eruptions belched massive amounts of carbon and sulfur dioxide into the atmosphere triggering a runaway greenhouse effect. The ocean began to evaporate adding more heat-trapping water vapor to the atmosphere. As Venus dried out, any plate tectonics would seize up, which would prevent it from burying its carbon dioxide. Once the water was completely gone, the huge carbon sink went with it. The carbon dioxide rich atmosphere turned Venus into an inferno. Visions of warm ocean waves lapping up against the shores of the huge plateau of Ishtar under blue skies were gone forever.

Venus has been basically an ignored planet for the past 30 years; Magellan ended its mission in 1994, and the European Space Agency’s (ESA) Venus Express and Japan’s Akatsuki missions are both completed. Nothing is currently orbiting Venus and nothing has landed on it since 1985. The clouds remain one of the most mysterious environments. It is dry and heavily laced with sulfuric acid, an unlikely place to look for life, but that is the problem, we assume life to be as we know it, not life that could possibly be. If sulfuric acid is mixed with water, it will dissolve organic molecules. At Venus, the atmosphere lacks plentiful water and laboratory studies have shown that amino acids are stable in concentrated sulfuric acid including some of the peptide bonds that link amino acids together to form longer chains, the backbone of complex organic chemistry that might give rise to life. Assuming anything in the field of science can be detrimental. The assumption that a world with sulfuric acid clouds automatically makes it hostile to life is a poor one. If there is no water, there is no reaction, so nothing dissolves. The reason experiments are performed in science is to test and prove ideas. The phosphine debate goes on, but it helped fire up the exploration of Venus in 2021, barely a year after the possible detection, with three new missions approved: NASA’s Veritas orbiter and Davinci atmospheric probe (complex and expensive), and ESA’s orbiter. All three will study the atmosphere and map the surface sometime after 2030. Rocket Lab intends to beat them to it.

The Rocket Lab mission is an atmospheric descent probe that relies on a simple scientific instrument: the Auto Fluorescent Nephelometer (AFN). Using a laser to scan its environment it will be able to sense the size and shape of various cloud particles. It will make organic molecules glow if they exist. It will not know exactly which organic molecules exist but will determine if they are there. The AFN is being tested flying on a drone around an active volcano in Hawaii to detect seas spray aerosols, sulfuric acid, dust, and ash. The data gathered can be assessed for accuracy and a data set will be built that can be used to interpret the probe readings at Venus. To get to Venus, the probe will launch on one of Rocket Lab’s Neutron rockets. The journey will take about four months after which the probe will detach from the carrier bus. The bus will burn up in Venus’s atmosphere having fulfilled its duty while a NASA designed heat shield protects the probe. It will begin exploring about 40 miles above the surface where the AFN, encased within a specialized pressure vessel, will begin its survey. Since it does not have a parachute, it will have only five minutes to collect data before it falls below the cloud deck followed by twenty minutes to transmit its data back to Earth. After that the intense heat and pressure will kill the probe. It is not designed to land on the surface as this is a simple, no-frills mission.

The main goal is to find signs of life at Venus. Future spacecraft under this project include flying an instrumented balloon system through the clouds to look for biomarkers, and eventually attempt to do an atmospheric and cloud sample return on a third mission. A successful Venus mission by Rocket Lab will be a victory for those hoping to do additional missions, and to make planetary exploration more accessible. It would make for a more efficient form of scientific discovery. Could Venus be favorable for life? Does it have life? It would be ironic to think that life might be discovered at Venus before Mars, Europa, or Enceladus. Or Venus might end up being the only other place in the Solar System besides Earth to have life! This is the reward for scientific research and our desire to explore and understand the unknown.