Lifeboat Foundation

Today we return to the Fermi Paradox to contemplate the notion of civilizations which neither expand outwards to colonize the galaxy nor go extinct, but exist as long-term, high-tech civilizations just on their own planet or solar system. To discuss the possible motives and reasoning we will look at the many arguments raised for and against space exploration.

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Microbial life may have resided within the first four kilometers of Mars’s porous crust.

Four billion years ago, the solar system was still young. Almost fully formed, its planets were starting to experience asteroid strikes a little less frequently. Our own planet could have become habitable as long as 3.9 billion years ago, but its primitive biosphere was much different than it is today. Life had not yet invented photosynthesis, which some 500 million years later would become its main source of energy. The primordial microbes — the common ancestors to all current life forms on Earth — in our planet’s oceans, therefore, had to survive on another source of energy.

Some of the oldest life forms in our biosphere were microorganisms known as “hydrogenotrophic methanogens” that particularly benefited from the atmospheric composition of the time. Feeding on the CO₂ (carbon dioxide) and H2 (dihydrogen) that abounded in the atmosphere (with H2 representing between 0.01 and 0.1% of the atmospheric composition, compared to the current approximate of 0.00005%), they harnessed enough energy to colonize the surface of our planet’s oceans.

Continue reading “Mars shows how even the simplest life forms can destroy their own planet” »

As in physics, paradoxes in biology really are just unsolved puzzles. Enter Peto’s paradox. Biologist Richard Peto noticed in the 1970s that mice had a much higher rate of cancer than humans do, which doesn’t make any sense. Humans have over 1,000 times as many cells as mice, and cancer is simply a rogue cell that goes on multiplying out of control. One would expect humans to be more likely to get cancer than smaller creatures such as mice. This paradox occurs across all species, too: blue whales are much less likely to get cancer than humans, even though they have many more cells in their bodies.

Fermi paradox

Continue reading “10 Paradoxes That Will Stretch Your Mind” »

Asteroids of this size are big enough to cause mass extinction events.

TL;DR: crazy predictions based on anthropic reasoning seem crazy only because they contradict our exaggerated expectations about too good future.

Nuclear War?! — We would be one of the first ones to go, but who or what would survive a nuclear war?

Posted on Big Think.

We continue our look at possible explanations why life may be very rare in the Universe by examining our planet itself, and looking at which of its characteristic might be important to intelligence developing and how improbable those traits are for a given planet in a given solar system.

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Continue reading “Fermi Paradox Great Filters: Rare Earth” »

We conclude our look at possible explanations why life may be very rare in the Universe by looking at the evolutionary pathway to intelligence and the hurdles between life starting on a planet and migrating off of it.

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Continue reading “Fermi Paradox Great Filters: Rare Intelligence” »

Writing in the Astronomical Journal, lead study author Scott Sheppard and colleagues at the Carnegie Institution for Science in Washington say they have found three “rather large” asteroids, one of which – 2022 AP7 – crosses the Earth’s orbit, making it a potentially hazardous asteroid (PHA).

With a diameter of about 1.1km to 2.3km, the team say 2022 AP7 is the largest PHA discovered since 2014 and probably in the top 5% of the largest ever found.

“Any asteroid over 1km in size is considered a planet killer,” said Sheppard, adding that should such an object strike Earth, the impact would be devastating to life as we know it, with dust and pollutants kicked up into the atmosphere, where they would linger for years.