Where Are the Aliens?

less than 1m read

·Nov 3, 2024

Let's talk briefly about the Fermi Paradox, since we're talking about aliens. For those listeners who don't know, Enrico Fermi was a famous physicist part of the Manhattan Project, and he said, "Where are the aliens?"

The universe is so large; there's probably so many planets that are capable of supporting life of some kind or another. Shouldn't we have seen them by now? Around almost every star, there is a contingent of planets much like our own solar system.

The number of stars that exists within a typical galaxy, like the Milky Way, is something like 200 billion, although the estimates go up to about 400. The number of galaxies that we can see is around 200 to 300 billion.

But the observable universe is just a small fraction of the entire universe. That means that the number of planets is absolutely astonishing—astronomical! Surely, given these numbers, it has to be the case that there are not only planets out there that are suitable for life, but the universe should be teeming with civilizations: far more advanced than ours, less advanced than ours, and some that are similar in advancement to ours.

So where are they?

Equivalent fractions on number lines

Worked example: using recursive formula for arithmetic sequence | High School Math | Khan Academy

View All

Evaluating compound boolean expressions | Intro to CS - Python | Khan Academy

How does the computer evaluate expressions with the logical operators and, or, and not to find out? Let’s explore the order of operations for compound Boolean expressions. Imagine we’re working on a program to check if a specific song matches the filters …

Great White Shark Hunting Patterns | When Sharks Attack

NARRATOR: South Africa’s Western Cape is notoriously dangerous. Almost one in four of all fatal great white attacks happen here. In other parts of the world, the most dangerous time to enter the water is at dawn or dusk, the times when white sharks typica…

The Fear of Death

[Music] Foreign death can only be interpreted by people who are alive. Yet since no one who is alive can simultaneously experience what it’s like to be dead, who then does death actually concern? This logic is oddly reassuring. Even so, if my doctor were …

Gyroscopic Precession

Hey everyone, it’s me, Derek from the channel Veritasium. I’ve been following this series by Destin on Smarter Every Day about helicopters, and gyroscopic precession is just one of those things that still blows my mind, as it did Destin. So, I’m here at t…

Is Glass a Liquid?

In 1994, a massive earthquake shook the Northridge suburb of Los Angeles, killing 57 people and injuring over 5000. The cost of damages was in excess of $20 billion. It’s earthquakes like this one that make us question just how solid is the earth beneath …

Things to consider when renting a home | Housing | Financial Literacy | Khan Academy

Let’s talk about things to consider when renting. So the first consideration is how much should you spend. A general rule of thumb is that you should spend a maximum of 30%—that’s 30% of gross income on housing costs. Now, I didn’t say rent here; I said h…

Where Are the Aliens?

More Articles