Its heavy-duty carbon dioxide atmosphere heaps an ocean’s worth of pressure onto its parched surface, a volcanic realm baking at 900 degrees Fahrenheit. It also rains sulfuric acid on Venus, but the surface is so hot — hot enough to liquify lead, in fact — that this rain evaporates before it ever hits the ground.

There is, however, one part of Venus that isn’t terrible: its cloud layer, part of which is oddly temperate. And in 2020, scientists announced the discovery of phosphine — a molecule frequently made on Earth by microbes — within that cloud deck. In the months and years since, the community’s confidence in that original phosphine detection has waned. But no matter: it’s already inspired an international squad of scientists and the California-based company Rocket Lab to team up and send their very own spacecraft to the hellish world next door.

The mission — tentatively called the Rocket Lab mission to Venus — is currently eyeing up the summer of 2026 for a launch date. It’ll send a robotic detective screeching through the Venusian atmosphere — but it’s not looking for phosphine. Instead, it’s going to search for the tell-tale glow of organic compounds.

“Why would you look for a biproduct of life if instead you can put your money on complex molecules that indicate life?” says Sara Seager, an astrophysicist and planetary scientist at MIT, and the science team lead on the mission.

The atmospheric diver won’t survive for very long, and it will have less than 30 minutes to perform its work. But if it succeeds, and it detects organic chemistry in that alien sky — not conclusive evidence of life, but perhaps the foundations of biology — then two things will suddenly become true. 

The first is that companies can send relatively cheap, hyper-focused spacecraft to worlds as extreme as Venus. “If we can show that Rocket Lab is capable of doing really serious science missions, at a cost that’s one-twentieth, or one-hundredth the cost of typical science missions… then we can open up a new era in space exploration,” says Christophe Mandy, a senior systems engineer and program manager for the Venus mission at Rocket Lab.

The second?

Once upon a time, perhaps hundreds of millions or billions of years ago, Venus went through a climatic apocalypse. It used to have an oceans’ worth of water and a relatively toasty, but survivable, temperature. But something nasty — perhaps several closely spaced and truly gargantuan volcanic eruptions — triggered a runaway greenhouse effect. Its ocean began to evaporate, adding more heat-trapping water vapor into the atmosphere. A dry world would see anything resembling plate tectonics shutting down, which in turn would prevent the planet from burying its carbon dioxide. And when its surface water eventually vanished, that huge carbon sink disappeared with it.

Prior to that cataclysm, Venus may not have looked too different from Earth. But today, it’s thoroughly awful, so much so that all the landers that were sent to the planet’s surface during the Cold War were annihilated in just a matter of hours or even minutes. That’s made studying Venus quite difficult, although remote observations and archival data from long-dead orbiters has hinted that the surface is alive with erupting volcanoes.

Despite the dearth of missions to Venus in the past few decades, scientists like Janusz Pętkowski, an astrobiologist at the Wrocław University of Science and Technology in Poland, are beguiled by Earth’s neighbor — particularly its cloud layer. “This is the most mysterious environment on Venus,” he says.

An astrobiologist being intrigued by Venus, an incandescent and desiccated wasteland, may sound a little strange. Those seeking evidence of alien life have tended to look for hydrated offworld environments, from the once-waterlogged lake basins of Mars to the oceanic moons of Jupiter and Saturn. Venus’s clouds are extremely dry, while also heavily seasoned with concentrated sulfuric acid, making it inhospitable to life as we know it.

For Pętkowski — another member of the Rocket Lab to Venus mission’s science team — the problem lies with that exact phrase: life as we know it.

Along with Seager and his other colleagues, Pętkowski has conducted extensive lab work to show that Venus’s clouds might be cozier than many would expect. Concentrated sulfuric acid certainly sounds hazardous, and a lot of YouTube videos showing things like hamburgers getting comprehensively eaten away by it do nothing to dissuade viewers of that notion. But Pętkowski says those videos can be misleading. “People think that organic chemistry cannot exist in concentrated sulfuric acid. And that is wrong,” he says. 

If you mix sulfuric acid with water and any organic molecules, including most of the biochemicals of life on Earth, they will be obliterated. But one can’t assume the same would happen in the clouds of Venus, which contain concentrated sulfuric acid but lack plentiful water. As a result, that concentrated sulfuric acid doesn’t seem to have the deleterious effect it has on Earth: the team’s recent lab work has shown that myriad amino acids are stable in concentrated sulfuric acid, as are some of the peptide bonds that link amino acids together to form larger chains — the backbone of the complex organic chemistry that might beget life.

“If your planet doesn’t have water, but it does have sulfuric acid, then paradoxically, some of these molecules can be stable,” says Pętkowski. “If there is no water, there is no reactivity, and no falling apart. That’s an extremely weird and unexpected result.”

In other words, we shouldn’t assume that the clouds of Venus might be empty of microbial life. “Assumption is the greatest enemy of scientific progress,” he says. “You shouldn’t assume anything before doing the experiment.” 

It’s also impossible to ignore the galvanizing effect that the 2020 detection of phosphine had on the scientific community. On Earth, it is naturally made in abundance by microbes, and the first foray of remote observations that year suggested a lot of it was present in Venus’s atmosphere. The detection has since been called into question; some teams, using a variety of observational techniques, have seen it (at varying concentrations), while others have not. Worth noting is the fact that it can also be made by intense volcanic activity, something that Venus almost certainly has.

“I'd say our understanding that phosphine is there is pretty good, with multiple detections over the last eight years,” says Jane Greaves, an astronomer at Cardiff University and one of the original discoverers of the phosphine signal. “However, it's puzzling why the abundance seems to vary, and that may be from different ways of processing the data or it may be true variability over time.”

Although the phosphine signal’s existence is debated heavily to this day, it had an immediate impact on both NASA and the European Space Agency, who green-lit three missions between them — two orbits, and an atmospheric probe — to Venus not long afterward. Each has a suite of objectives, from sniffing out the chemistry of the sickly sky to mapping out the world’s weird surface geology. And all three are set to arrive sometime after 2030.

Rocket Lab wants to beat them all to the punch.

NASA and ESA’s upcoming endeavors are like Swiss army knives: equipped with an array of tools designed to answer multiple questions about Venus. Seager, though, is thinking differently about interrogating Earth’s neighbor.

She is the leader of the Morning Star Missions to Venus project, a consortium of scientists and engineers who want to unearth that bizarre planet’s mysteries. “It goes back to phosphine on Venus,” she says. “I took that opportunity to ask ourselves: what would we want to do if we could go to Venus with one or more very, very focused missions?”

The project has one ultimate objective: “We want to find signs of life on Venus,” says Seager. Future spacecraft concepts include flying an instrumented balloon system through the clouds to look for biomarkers, and an even an atmosphere and cloud sample return program. But you’ve got to start somewhere, and that will be the Rocket Lab Mission to Venus, and it wants to answer a single question: is there organic chemistry in the Venusian clouds, or not?

“We’re not looking for phosphine,” says Seager. She points out that phosphine is something that can be made by life, but also by other natural sources. Phosphine may not even be in the Venusian atmosphere either. Why not instead look for complex organic chemistry? Some especially baroque kinds of organic molecules tend to be associated with life on Earth more than any geologic or environmental process.

The Rocket Lab mission is an atmospheric descent probe that relies on a single scientific instrument: the AutoFluorescence Nephelometer, or 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, revealing their previously hidden existence (if, indeed, they are there in the first place). “We will not know exactly what organic molecules we will have,” says Pętkowski. “But we will know if they are there.”

An AFN is currently being tested in an environment standing in for the Venusian cloud deck: Hawai‘i’s Kīlauea volcano. Not only is it nearly constantly erupting, but it’s “the second largest emitter of sulfur dioxide on Earth — and this can be oxidized to sulfuric acid and grow into larger aerosols resulting in volcanic fog, or vog, that is similar to the Venus clouds,” says Christopher Carr, a program engineer and scientist at Georgia Tech and member of the Morning Star Missions to Venus team.

The AFN is being flown around the volcano on a fixed-wing drone and will try to detect things like sea spray aerosols, sulfuric acid, dust and ash. By comparing the AFN flight experiments with ground-based measurements and laboratory sample tests, the team can assess the accuracy of the AFN while also building a reference data set that scientists can use to interpret the probe readings taken while on Venus.

If the AFN stands up to scrutiny on Earth, the team must then get it into Venus’s clouds. And that’s where Rocket Lab’s engineering magic comes into play.

The spacecraft, with its singular focus and solitary scientific instrument, has no frills. “The number of ways it can go wrong are as low as possible,” says Mandy, the program manager at Rocket Lab. After it launches on one of the company’s Neutron rockets, it will reach Venus in four months. After that, an AFN-containing probe will detach from the spacecraft bus, and the bus will perish, having fulfilled its transportation duties.

This is where the (real) fun begins. The probe will enter the Venusian atmosphere and will travel at supersonic speeds for three agonizing minutes. It will be protected from vaporization by temperatures of up to 4,500 degrees Fahrenheit, all thanks to a heat shield designed by NASA’s Ames Research Center in California’s Silicon Valley.

At the very top of the Venusian cloud layer — about 40 miles above the surface — the probe will have decelerated, and the AFN, trapped within a specialized pressure vessel, will begin its survey. It will have just five minutes to peruse the clouds before the probe falls out of the cloud layer, after which it will have just 20 minutes to transmit its invaluable data back to Earth. After that point, the planet’s intense temperature or pressure will quickly kill the probe.

The Rocket Lab mission to Venus is ambitious, which is why it’s somewhat surprising that most of those building it are doing so part-time. “Most of the engineers are working nights and weekends on this, rather than being fully allocated,” says Mandy. Rocket Lab’s commercial missions remain everyone’s primary focus; the company’s Venus probe only exists because the company is making money elsewhere.

Speaking of which, this mission is also supposed to be cheap by design. How cheap, exactly? Rocket Lab wouldn’t reveal a figure, but a recent estimate put it at no more than $10 million, which would make it roughly 50 times less expensive than one of NASA’s two upcoming polymathic missions to Venus. If it works, then that’s good news for all planetary scientists. If not, then it wouldn’t come as a huge surprise.

“Doing space for cheap is very, very hard,” says Paul Byrne, a planetary scientist and Venus evangelist at the Washington University in St. Louis. Just look at the recent cavalcade of private missions to the Moon: although the NASA-sponsored Blue Ghost spacecraft, built by Texas-based Firefly Aerospace, successfully touched down on the lunar surface and conducted some scientific investigations, several others had grim fates. For example, Intuitive Machines, another (frequently successful) Texas-based company, flew its Athena spacecraft onto the Moon — but when it landed, it toppled over to lethal effect.

The nearby, quiescent, atmosphere-lacking Moon is troublesome enough. But Venus is orders of magnitude more perilous. “I hope they pull it off for a variety of reasons: programmatic, technical, and scientific,” says Byrne. “But if we lose contact with this probe, will the funding bodies behind it be willing to push on anyway?” Will the future Morning Star Missions to Venus still ultimately fly? “What is their appetite for risk?”

A win for Rocket Lab would be a victory for those hoping to make planetary exploration more accessible, for those wishing for a more efficient and democratic form of scientific discovery. Will the mission reveal the secrets of Venus’s skies? “I’m a natural optimist,” says Pętkowski. He’s happy they are going to try.

Seager strikes a more filmic note of hope. “A new dawn is rising,” says Seager.