Life Among The Stars?
Two possibilities exist: either we are alone in the Universe or we are not. Both are equally terrifying.
Arthur C. Clarke
Since the first (erroneous) belief that Mars was crisscrossed by canals, mankind has looked at the planets of the solar system and wondered if they harbored life.
Source: Wikipedia – Meyers Konversations-Lexikon (German encyclopaedia), 1888.
Ultimately, better telescopes and robotic probes would show that Earth is exceptional in harboring intelligent life, as well as a very dense biosphere.
While the absence of alien civilizations in our solar system proved disappointing (or maybe reassuring), the presence of simpler life forms might be more likely than previously thought. A series of recent discoveries might indicate that not only Mars but also Venus could harbor microbial life. This would open the way to expecting other celestial bodies to do the same as well.
Potential Life On Mars
Ancient Life On Mars
We know that in the distant past, Mars was much warmer, with a denser atmosphere and flowing water. For a long time, we assumed that the atmosphere and water had been blown away by the solar winds, leaving the planet as a colder and desolate desert today.
We recently learned this is not true, and that the crust contains enough liquid water in fractured rocks to cover the whole planet, deep under 10-15 km of rocks. Life may exist at that depth, fed by the energy provided by geological activity, but it will be impossible to say for decades, at least.
In any case, this ancient warmer and wetter Mars would have been an ideal environment for life to develop.
Minerals Linked To Biological Activity
In July 2024, NASA announced that the Perseverance rover had maybe found signs of life in the Martian past.
Source: NASA
More precisely, it found veins of white calcium sulfate precipitate turned into rock, which can be formed by life on Earth, but also could have been produced by geological process.
Next to it, mineral “leopard spots” were found in the rock, millimeter-size spots containing iron and phosphate. On Earth, such spotting can form when organic molecules react with rusted iron. These reactions, in turn, can fuel microbial life.
Source: NASA
None are definitive proof of life in Mars’ past, but they are very good indicators of potential life. If these mineral deposits were formed by alien life, a deeper look at the collected samples should help prove it.
The upcoming and still in development $11B Mars Sample Return mission, would allow us to collect samples. However, the mission is currently too expensive, and NASA is looking at private companies to find alternative plans to cut costs.
Previously Ignored Signs?
Methane
If there was life on Mars, could it still exist today, in a dormant or hidden form?
One signal that this might be the case has been a perplexing phenomenon. The Martian atmosphere contains traces of methane, a gas usually associated on Earth to anaerobic fermentation by microorganisms and considered a strong theoretical biosignature.
But of course, it can also be produced from geological activity, like volcanoes. With several dormant massive volcanoes on Mars, it is possible some residual activity could explain a small steady production of methane.
This was the dominant explanation until scientists noticed that the Martian methane followed a seasonal cycle, with a peak amount in late northern summer. It also seems to be more produced at night and disappearing during the day.
While seasonal methane could partially be produced by variation in UV exposure, this is just too strong of a variation to explain it.
So, some scientists are wondering if the explanation could be biological. After all, you would expect life to be active following the seasons, especially in such a cold environment, similar to how Earth’s northern ecosystems are mostly active only in summer.
Trace of formaldehyde, which could be the byproduct of the bio-oxidation of methane, has also been detected in 2005. For now, NASA has ruled out demonstrating the presence of life on Mars.
Vikings Probes
Earlier, in the 1970s, NASA sent the two Viking landers to Mars to try to detect life signs.
The results were considered at the time as inconclusive to any sign of life. Still, it was somewhat confusing: one experiment (Labeled Release (LR) experiment) detected signs of metabolism; however, another experiment found no trace of organic material.
Source: Phys.org
Scientists involved with the Viking experiment, Gilbert Levin and Patricia A. Straat, have come back in the 2010s to discuss that in their view, the experiment most likely demonstrated that there was life on Mars.
One key argument is that when heated at 160C (a sterilizing temperature), the samples stopped showing signs of metabolism. The metabolizing also slowed at 50C and was completely absent when storing the soil in the dark for two months at 10C.
Another argument is that the failure to detect organic compounds was more a problem due to the soil containing perchlorate (destructive when heated), than an actual absence of organic molecules.
Meanwhile, the Curiosity rover detected organic molecules in Mars’ soil in 2014.
Martian life could take the form of methanogens (microorganisms that produce methane as a byproduct), halophiles (which can tolerate high salt concentrations as well as severe radiation and low oxygen concentrations), or some type of “cryptobiotic” microorganism that lies dormant until reactivated, such as by a nutrient solution like the one in the LR experiment.
Phys.org
Levin has nevertheless struggled to get his interpretation of the Viking’s data published in serious scientific publications.
In large part, because discussing the proof of alien life can be quite a taboo among astronomers looking to preserve their academic reputation.
“At a meeting of the Canadian Space Agency, I met Dr. Sherry Cady, the editor of Astrobiology. She invited me to submit a paper for peer review. I did and it was promptly bounced, not even sent out for review because of its life claim.
“Pat and I decided we would produce a paper that would withstand the utmost scientific scrutiny. It took years of countless renditions and compliance with or explanation away of a myriad of reviewers’ comments, but we persisted until we disposed of every adverse comment.
It would take them 20 years to manage to finally get published in 2015, in a paper titled “The Case for Extant Life on Mars and Its Possible Detection by the Viking Labeled Release Experiment”.
Potential Life On Venus
Phosphene In Venus Clouds
Mars has always been the strongest candidate for some form of alien life, past or present, due to its past ocean and flowing water, as well as its still existing, although cold and thin, atmosphere.
On the other hand, one place scientists never seriously expected to find detectable signs of life is Venus.
The planet, maybe once a twin of Earth, suffered from a catastrophic runaway greenhouse effect that turned it into a literal hell:
- A thick atmosphere made mostly of CO2 (96%), with sulfuric acid clouds, with a pressure of 92 Earth’s atmosphere.
- A surface temperature on average at 464 °C/867 °F, hot enough to melt lead.
- Intense volcanic activity.
- Barely rotating, resulting in the planet’s day being longer than its year.
- No magnetic field to speak of.
Quite literally, every one of these harsh conditions would be expected to sterilize the planet.
So it was a massive surprise when analyses of Venus’ upper atmosphere in 2020 by researcher Dave Clements and his team found traces of phosphine, a compound produced on Earth by decomposing organic matter.
Source: ACS
This discovery has long been debated, to be confirmed in 2024. They also found that phosphine detection appeared to follow the planet’s day-night cycle.
Ammonia
And then another discovery was that ammonia is also present in the clouds of Venus, which is another likely biomarker.
“There may be something really exotic going on – but none of the normal chemical processes that we are aware of can produce the amounts of phosphine and ammonia,” Clements said, explaining that his team’s recent findings point to even greater amounts of the molecules in Venus’ clouds compared to the findings from 2020, and lower in the planet’s atmosphere.
“Something is going on that we can’t understand. The chances that what we’re seeing are actually signs of life are probably between 10-20 percent at this point.
USA Today
These discoveries were made at 50km/31 miles above the surface altitude range, where the conditions of temperature and pressure are somewhat similar to Earth, far from the acidic hell of the surface.
The presence of ammonia also changes how we see the planet’s clouds.
While they are rich in sulfuric acid, a publication from 2021 in the prestigious scientific magazine PNAS titled “Production of ammonia makes Venusian clouds habitable and explains observed cloud-level chemical anomalies” shows that the presence of ammonia reduces the acidity of the cloud.
“A consequence of the presence of NH3 is that some Venus cloud droplets must be semisolid ammonium salt slurries, with a pH of ∼1, which matches Earth acidophile environments, rather than concentrated sulfuric acid.”
So not only the place could be not as hostile as we believed until now, but we know of lifeforms on Earth that could survive it today.
“The source of NH3 is unknown but could involve biological production; if so, then the most energy-efficient NH3-producing reaction also creates O2, explaining the detection of O2 in the cloud layers. As a result, the clouds are no more acidic than some extreme terrestrial environments that harbor life.
Life could be making its environment on Venus. The model’s predictions for the abundance of gases in Venus’ atmosphere match observation better than any previous model and are readily testable.”
Overall, both phosphine and ammonia are molecules that should not be produced inorganically in an oxygen-rich atmosphere like Venus, or hydrogen-rich ones like Jupiter and Saturn.
Still, it could theoretically be produced by volcanoes or exotic UV-induced chemical reactions.
So, while this is not absolute proof life is present on Venus, we either need two different yet undiscovered chemical processes or consider the possibility of only one lifeform to explain these observations.
Where Could these Bacteria Come From?
Assuming these atmospheric anomalies on methane, ammonia, and phosphine on Mars & Venus are due to bacterial life, where did such life come from?
One theory is that it could have originated locally, as both planets had much more friendly environments in their early life, warmer for Mars, and colder for Venus. So the life we (maybe) detected could be the survivors that adapted to the changing conditions, the way on Earth extremophile bacteria have evolved to thrive in salt lakes, thermal vents, and acid pools.
Another option is panspermia. The idea that life, including maybe life on Earth, did not originate from the planet but from space.
An alternative version of panspermia is that life originated on one planet of the solar system (likely Mars or Earth), and asteroid impacts spread bacteria to the other planets.
Source: Astrobiology
It is not so far-fetched, as we found on Earth rock originated from Mars, and we know bacteria and even complex organisms like tardigrades can survive the vacuum of space.
We even have found moss on Earth that can survive several days in Mars-like conditions.
Considering we do not know how life appears from dead inorganic material, it is impossible to say.
If we find life on Mars and/or Venus, if it is very similar to Earth life, panspermia is the likely scenario. If it is very different (for example, if DNA/RNA and proteins are not used), then a spontaneous separate origin would be more likely.
Of course, in any case, native life on Mars or Venus would also increase the chance of finding life elsewhere, like, for example, in the underground oceans of Europa and Enceladus.
Investing In Mars
We are too early to invest in terraforming megaprojects or Martian real estate. But a handful of companies are working hard in building the stepping blocks that will make it possible to land the first man on Mars, and later on colonize the planet.
A key part will be reusable rockets, dramatically reducing the cost of launching equipment into orbit and deep space. This effort is mostly currently led by Elon Musk’s SpaceX, a private company, with other rocket companies catching up quickly.
Another factor will be to create a self-sustaining space-based economy and Martian economy, able to support terraforming efforts without depending on Earthlings’ willingness to finance it “for free” (follow the links for more details on how it would work).
You can invest in aerospace companies through many brokers, and you can find here, on securities.io, our recommendations for the best brokers in the USA, Canada, Australia, the UK, as well as many other countries.
If you are not interested in picking specific aerospace companies, you can also look into ETFs like ARK Space Exploration & Innovation ETF (ARKX), iShares U.S. Aerospace & Defense ETF (ITA), or SPDR S&P Aerospace & Defense ETF, which will provide a more diversified exposure to capitalize on the aerospace industry.
Or you can read our article about the “Top 10 Aerospace and Defense Stocks”.
Investing In Space Companies
1. Rocket Lab
Rocket Lab is one of the most serious contenders in the reusable rocket market. The company has initially focused on small rockets, with the Electron launch system (320 kg of payload), which is progressively being turned into a partially reusable rocket. So far, Electron has deployed 177 satellites in 44 launches.
Later on, Rocket Lab is looking at creating a medium-size reusable rocket, the Neutron, comparable to Flacon 9 (8,000 kg to LEO in fully reusable mode, 1,500 kg to Mars or Venus). The Neutron will be powered by a methane-burning rocket engine (like Starship), which seems to become the trend for the next generation of rockets.
The company is remarkable for its fully vertically integrated satellite manufacturing process, allowing it to optimize costs and design speed.
This resulted in multiple contracts with NASA & the US government, including a $515M military satellite contract. and a civilian $143m contract for Globalstar.
Rocket Lab is also a major manufacturer of solar panels for satellites after its 2022 acquisitions of SolAero Technologies, with 1000+ satellites powered by these panels, and 4MW solar cells manufactured in total.
Source: Rocket Lab
For now, its launch system is reliant on outside suppliers, but a series of strategic acquisitions should change that, replicating in the launch system the vertical integration already achieved in satellite design and manufacturing.
The company is also looking at the possibility of a telecom LEO constellation to generate recurring revenues. It is also contributing to research for in-space manufacturing with Varda Space Industries and orbital debris inspection.
While SpaceX had Elon Musk’s business talent to develop its technology from scratch, Rocket Lab used a mix of R&D and acquisitions to vertically integrate the technology required. This has proven very successful in satellite manufacturing, and they are now looking to replicate this strategy for reusable rockets.
Considering the existing cash flow from satellite production & the Electron successes, Rocket Lab is a good candidate to catch up with SpaceX’s headstart.
For those interested in investing in this company, make sure to take a look at the top stock brokers in your region (e.g. for USA, UK, Canada, and Australia) or our article on the 10 Best Investing Apps.
2. Virgin Galactic
The company was founded by Richard Branson and is focused on space tourism.
The tickets are in the $250,000-450,000 range, with a long waiting list. The first customers seem to be ecstatic with their experience:
“I always knew it was going to be the most extraordinary experience of my life. I always knew that. And people kind of told me it was going to be. But then when it is… and it’s on another level to the experience you thought you were going to have… then it’s very difficult to explain.”
“This has been the best day of my life, the most sensational day of my life. And you can’t get any better than that. It exceeded my wildest dreams.”
As we discussed before, space tourism might be THE center of the future Martian economy.
This is because not only will Mars provide a unique experience, but it will also have some of the most impressive features in the entirety of the solar system:
- The largest canyon in the solar system (4,000 km long, 200 km wide, and up to 7 km deep).
- A volcano of 21.9 km in height (72,000 ft) and roughly as large as France or the state of Arizona.
Source: Wikipedia
Before Mars, Virgin Galactic is aiming to become the leader of orbital (and later maybe lunar) tourism, more in reach of our current technical abilities before a Chinese or SpaceX Mars landing.
Virgin Galactic has been working on improving its unit economics, with a new launch system, the “Delta”, able to carry 6 passengers instead of 4, and to perform 8 flights/per month instead of just one.
Together, these 2 improved metrics should boost revenue per unit by 12x, with a payback time of less than 6 months for each Delta shuttle. The Delta flight test is expected in mid-2025.
Source: Virgin Galactic
Markets were concerned when it was announced that Branson would not invest further into Virgin Galactic. Especially following the layoff of 185 employees and a pause of space flights in 2024, to wait for the arrival of the Delta shuttle and reduce cash burn speed.
Still, Virgin Galactic is forecasted to have enough cash to run until 2025 or 2026. So if the development of the Delta flight system goes smoothly (a risky proposition in the aerospace industry), the company should be able to focus on restarting and growing cash flow, with a system that is profitable on a unit basis. And make the company turn cash flow positive in 2026.
Source: Virgin Galactic
(It should be noted that Virgin Galactic is different from Virgin Orbit. Virgin Orbit filed for bankruptcy in April 2023, and provided launch services for small satellites, with Rocket Lab acquiring the company’s Long Beach facility, manufacturing, and tooling assets).
The recent bankruptcy of Virgin Orbit and distancing from Virgin Galactic by founder Richard Branson has damaged the company’s image with investors, resulting in a plummeting stock price in 2023 & 2024.
Source: Virgin Galactic
At the same time, the previous customers’ satisfaction, a clear plan for a profitable design (Delta shuttles), and a long waiting list of potential clients show that the company might still be viable even without raising more funds. So a lot will rely on the success of developing, manufacturing, and operating the Delta shuttle and achieving it before the end of 2025.
If this is the case, the much lower valuation would create an opportunity for investors to grab the company’s shares at a discount.