An Abundance of Extraterrestrial Life

After the horrific event in Utah yesterday, I couldn’t help but think about how precious life really is.

And while such a heartbreaking assassination is not the kind of current event that I would research and write about in The Bleeding Edge, I will write about life.

Specifically, a place where life is abundant.

Space.

The Substance of Life

Yesterday, a team of researchers from NASA published exciting research in Nature – Redox-driven mineral and organic associations in Jezero Crater, Mars.

A redox reaction is simply a reaction whereby one substance loses electrons, which is known as oxidation, and another substance gains electrons, which is reduction.

It’s a reaction that is commonly associated with life.

NASA’s Perseverance rover – which has now been on Mars for four years, six months, and 24 days – collected a unique rock sample from an ancient riverbed in the Jezero Crater.

The rock sample demonstrates the most compelling evidence of ancient extraterrestrial microbial life that we’ve ever seen.

Perseverance rover from July 2024 | Source: NASA

The sample was taken from sedimentary rocks – composed of clay and silt – which we know on Earth tend to preserve ancient microbial life. After analysis, the researchers discovered the sample is rich in organic carbon, sulfur, oxidized iron, and phosphorus.

Closeup of Mars Sample | Source: NASA

The above photo is a close-up of the sample, believed to contain biosignatures. The “leopard spots” as described by NASA – which are quite easy to see – were the giveaway, indicating chemical reactions that support life.

The two key minerals discovered are vivianite and greigite.

Vivianite, which we have on Earth, is commonly found in sediments, peat bogs, and near organic matter.

Greigite is produced by certain kinds of microbial life on Earth.

Knowing that, it’s easy to understand why the team at NASA is so excited.

A Surprising Discovery

It gets even more interesting.

This discovery was found in younger (relatively speaking) sedimentary rocks than those that have typically been investigated by Perseverance.

The past thinking was that signs of past life were most likely to be found in older sedimentary rocks. Therefore, that has been the priority.

But this discovery suggests that Mars could have been habitable for a longer period of time than previously believed.

It also means that there are likely a lot more signs of past life on Mars to be discovered. It is likely to be microbial, as opposed to flora and fauna, but it is life, nonetheless.

Which raises the question…

If there was life on Mars, such a close neighbor of ours, what about the rest of the solar system?

We’ve long known that Jupiter’s Europa, and Saturn’s Titan and Enceladus, are the most likely places for life other than Mars, due to their subsurface oceans and the likelihood of hydrothermal vents.

All that’s left for us to do is to get there and investigate. And there’s a lot happening on that horizon…

• NASA’s Dragonfly mission to Titan will launch in 2028 and arrive in 2034 to explore Titan and its surface by sending a rotorcraft to measure Titan’s organic surface materials.
• The Enceladus Orbilander is a mission concept that would orbit Enceladus and then land on the moon for research.
• The Europa Clipper already launched on October 14, 2024, and is on its 1.8-billion-mile mission to reach Europa. It will arrive in April of 2030. The Europa Lander is a proposed mission to send a follow-on spacecraft to study Europa’s surface.

Artist Rendering of NASA Dragonfly rotorcraft on Titan | Source: NASA

But that’s just our solar system, our tiny little corner of the Milky Way galaxy that we find ourselves in, which itself is insignificant in comparison to the scale of the entire universe.

Is there life out there?

The Equation of Intelligent Life

While we don’t yet have definitive proof, I can say with absolute certainty that life is abundant in the universe.

The distances are so incredibly vast that discovery presents a challenge for such an underdeveloped civilization as ours. After all, we’re nowhere near having a warp drive.

But life is abundant, nonetheless. It’s all in the numbers.

Specifically, the Drake equation is a useful proxy to determine the number of active, communicative alien civilizations in the Milky Way galaxy.

Here is what the Drake equation is composed of:

The Drake equation is unique in that there is no single answer. There is no way to solve it. We can’t possibly know with specificity the value of each variable.

In that way, it is a probabilistic way to estimate the number of intelligent civilizations in the Milky Way Galaxy that “we” might be able to communicate with at any given time.

So, let’s work the problem together, based on reasonable assumptions:

• R* – let’s assume this is 10 because we already know from empirical evidence that roughly 10 stars are formed every year in the Milky Way.
• fₚ – let’s assume 90%, nearly all stars have planets.
• nₑ – let’s assume 10%, which I believe is very conservative, as life can exist in very harsh environments, so the percentage is most likely higher.
• fₗ – let’s assume 100%, since where life can exist, it will.
• fᵢ – let’s assume 5%, which I also believe is conservative, since where life is sustainable, over long enough periods of time, intelligent life will evolve.
• f_c – let’s assume 50%, it seems quite logical that intelligent life will find ways of building communication technology (I admit, the number is probably much higher).
• L – let’s assume that, on average, intelligent life will last for 500,000 years, a duration that is conservative if we consider how long a planet is habitable (again, the actual number is probably higher).

Here’s what we get:

N = 10 x 0.9 x 0.1 x 1 x 0.05 x 0.5 x 500,000

Therefore, the number of civilizations in the Milky Way that we might be able to communicate with based on the above assumptions is:

11,250

Again, that number can be higher or lower based on the assumptions we make for the Drake equation… feel free to play around with the assumptions to see for yourself.

But no matter what reasonable assumptions we make, it is a big number. And here’s the kicker…

That’s just for the Milky Way galaxy.

There are somewhere between 200 billion and 2 trillion galaxies… in our universe.

That means that there is somewhere between 2.25 x 10¹⁵ and 2.25 x 10¹⁶ intelligent civilizations in our universe that we might be able to communicate with.

The numbers are simply mindboggling.

And again, no matter what assumptions we make, it is still a massive number.

Life is precious, and it is also abundant in our galaxy and in our universe.

Let’s wish, hope, and pray for peace and the preservation of and the discovery of life.

Jeff