Life in the Solar System: What Venus, Mars, and the Ocean Moons Are Trying to Tell Us

Is there life in the solar system beyond Earth? From life on Venus to life on Mars to the ocean moons, the search keeps turning up maybes instead of answers — and the Drake equation shows exactly why that’s the right question to be asking. I’ve had a card on my fridge for years with a line from Michio Kaku on it: “Physists are made up of atoms. A physicist is an attempt by an atom to understand itself.” But I think Carl Sagan said it first.

In Cosmos in 1980, he called us “a way for the cosmos to know itself,” and Kaku’s line reads like an echo. If the cosmos is trying to know itself, why would it only be trying here?

What the Drake Equation Actually Asks

Frank Drake wrote his equation in 1961 as the agenda for the first serious meeting on the search for extraterrestrial intelligence, at Green Bank, West Virginia. Carl Sagan was in the room. The equation multiplies seven terms — how fast stars form, how many of those stars have planets, how many planets could support life, how often life actually starts, how often it becomes intelligent, how often it tries to communicate, and how long a civilization stays detectable before it goes quiet. Multiply all seven and you get N: the number of civilizations in our galaxy we could actually talk to.

Here’s the part people skip. Drake didn’t build a calculator. He built a list of what we don’t know. Most of the seven terms are still guesses dressed up as inputs. Feed in optimism and you get a galaxy full of neighbors. Feed in pessimism and you get an empty one. Same equation, opposite universes.

The term this whole post cares about is fl — the fraction of habitable worlds where life actually gets started. It’s the term Mars, Venus, and a handful of icy moons are in a position to test directly, right now, with hardware we’ve already built or are about to launch.

The Fermi Paradox: Where Is Everybody?

If life is even a little bit common, the galaxy should be loud. Billions of stars, billions of years — and nothing. No signals, no probes, no evidence anyone else ever got here first. That silence has a name: the Fermi paradox, after Enrico Fermi, who is said to have asked “where is everybody?” over lunch at Los Alamos around 1950.

One proposed answer is the Great Filter — some step on the road from chemistry to a starfaring civilization so improbable that it filters almost everyone out before they’re ever loud enough to notice. The uncomfortable question is where that filter sits. Behind us, or ahead of us.

If the filter is behind us — if getting from dead rock to simple life is the hard part — then finding life on Mars would be wonderful news: proof we already cleared the hardest gate. If the filter is ahead of us, finding life on Mars is a warning shot. Either way, life in the solar system is the fastest test of that question we have, decades before we could ever test it around another star.

But seriously if there is life out there, I would not blame them for locking their doors as they fly by. We have to stop fighting with ourselves.

Life on Venus: A Gas, a Debate, a Cloud City

In 2020, a team led by Jane Greaves reported phosphine in Venus’s clouds — a gas that, on Earth, is made almost exclusively by microbes and by us. The announcement lit up every science desk on the planet. Then the follow-up studies started coming in, and most of them found nothing. A few, using different instruments and looking deeper into the clouds, found hints again. Five years on, the debate hasn’t closed. That’s not a failure of science — that’s what a hard measurement at the edge of detection actually looks like.

The next real answer comes from that Rocket Lab probe — and even its own lead scientist says success would only prove the ingredients are there, not that anyone’s home. And if you want the long-shot dream version: NASA’s Langley engineers spent real hours sketching HAVOC, a floating cloud city where the pressure is close to Earth’s and gravity is nearly the same. Somebody built the Lando Calrissian version of Venus exploration, and I’m not going to pretend that isn’t delightful.

Life on Mars: What Perseverance Found

Perseverance drilled into a mudstone called Cheyava Falls and pulled up something NASA is willing to call a potential biosignature — pale “leopard spots” ringed with iron and phosphate minerals, the kind of pattern that on Earth usually means microbes were metabolizing something nearby. NASA’s own project scientist put it plainly: non-biological explanations are less likely, but they can’t be ruled out yet. That’s not “we found aliens.” That’s the strongest card this solar system has ever dealt us — and it’s still just a card.

The Angry Astronaut has been loud about this, and on the facts, he’s more right than people probably assume. Here’s his own case, in his words:

I’ll give him this much, generously: the question of why we haven’t flown a dedicated life-detection instrument since 1976 is a fair one, and it deserves a better answer than budget politics. Where I’d slow him down is the leap from “potential biosignature” to proof — NASA’s own scientists haven’t made that leap, and neither should we, however satisfying the certainty feels.

I’ll give him this much, generously: the question of why we haven’t flown a dedicated life-detection instrument since 1976 is a fair one, and it deserves a better answer than budget politics. Where I’d slow him down is the leap from “potential biosignature” to proof — NASA’s own scientists haven’t made that leap, and maybe we should. At the very least we need to send the courier NOW! Stay Angry About Space!

The Sample Tube Waiting on Mars

Perseverance already sealed a rock core — the actual Cheyava Falls sample — in a titanium tube, sitting on the Martian surface right now, waiting for a ride home. In January 2026, Congress effectively cancelled Mars Sample Return. Not because anyone stopped believing the sample mattered — the program had been hit by real delays and real cost overruns for years. But the effect is the same either way: the courier got cancelled.

China’s Tianwen-3 is scheduled to launch in 2028 and bring Martian material home by 2031 — a simpler, single-site mission, aimed at exactly this kind of question. If “is there life on Mars” gets answered in a lab, it’s increasingly likely that lab will be Chinese, not American. The rock isn’t going anywhere. The question is who shows up to carry it — and whether the answer changes how we search for life in the solar system everywhere else.

Life in the Solar System Beyond Mars: Ocean Worlds

The “habitable zone” — the band around the Sun where a planet’s surface could hold liquid water — only measures one thing: sunlight and distance. Venus orbits at 0.72 AU, tucked inside the zone’s conservative inner edge near 0.99 AU. Mars orbits at 1.52 AU, comfortably inside the standard outer edge of 1.70 AU, though stricter models push that edge closer and leave Mars just outside. Depending on which model you trust, Mars is either barely in or barely out. That’s how fuzzy the “zone” really is — and it only ever described surface water in direct sunlight.

Which is why the most serious candidates for life in the solar system right now aren’t in the zone at all. They’re sealed under ice, running on chemistry the Sun never touches.

What If Life Comes Easily?

Here’s what a second, truly independent origin of life would actually do to Drake’s equation: it would take fl — the term nobody has ever had real data for — and turn it from a guess into a measurement. Not zero. Not vanishingly small. Measured, and larger than one.

The Cosmos Knowing Itself

Which brings me back to the fridge. Sagan’s line was never really about extraterrestrial biology — it was about matter waking up enough to ask what it is. Kaku’s card is the same insight, wearing a physicist’s coat instead of an astronomer’s. Neither man was a panpsychist. Sagan meant that awareness emerged, slowly, through billions of years of evolution. That’s a claim the data can actually test.

Panpsychism is a further step — the idea that mind isn’t something that emerges, but something fundamental, present in some form in all matter, atom included. Nothing on Mars or in Venus’s clouds tests that claim, and I want to be honest about the difference. I hold panpsychism as a view I find beautiful, not a finding Perseverance confirmed.

That’s a suggestive parallel, not an equivalence, and I’d rather keep it honest than make it bigger than it is.

But honesty cuts both ways. If Vajrayana is right that mind-streams extend into realms we haven’t counted — and I don’t know that it is — then the practice doesn’t wait around for proof. It’s been extended to whatever’s out there since long before the Drake equation existed. It’s called the Four Immeasurables, and it names no planet:

That’s not a prayer with an edge where Earth stops. It never had one.

The atom is still trying to understand itself. We just don’t yet know how many places it’s trying from.

QP

Further Reading:

If you want to go deeper on the physics side of this question,

→ Panpsychism: Could It Really Be True? is where I first laid the case out, and the

→ Is Consciousness Everywhere? podcast episode picks it back up.

If you want the primary sources behind the case for life in the solar system — the Drake equation, the Fermi paradox, life on Mars, and life on Venus — here’s where to go next:

→ Dissolving the Fermi Paradox — Sandberg, Drexler & Ord (arXiv, 2018) — the paper behind this post’s one-in-three odds that we’re alone, recalculating the Drake equation with honest ranges of uncertainty instead of single guesses.

→ Where Are They? — Nick Bostrom (MIT Technology Review, 2008) — the essay that explains why finding life on Mars could be bad news for the Fermi paradox, not good.

→ Phosphine Gas in the Cloud Decks of Venus — Greaves et al. (arXiv, 2020) — the original paper behind the life on Venus phosphine debate.

→ Perseverance’s PIXL Finds Vivianite, Greigite in Cheyava Falls Sample — NASA’s own write-up on the strongest evidence yet for life on Mars.

→ Panpsychism: Could It Really Be True? — where I first laid out the case connecting physics and dharma — still the site’s all-time most-read post.

→ Is Consciousness Everywhere? Panpsychism, Quantum Physics, and the Buddha Dharma — the podcast episode that picks the panpsychism question back up.