Infographic: How Many Aliens Are There In Our Galaxy?

The Drake Equation is the most famous, respected mathematical model for predicting alien life. Now, it’s an easy-to-read infographic.

Can you read that? (Of course you can’t, without a key.) It’s the Drake Equation, a mathematical model to predict the number of detectable extraterrestrial life forms in the galaxy.

The gist of it says that measurable alien life in our galaxy equals the number of stars, surrounded by habitable planets, that produced not just life but intelligent life, that would go on to produce a measurable transmission we could detect, and continue sending it. The concept is understandable, but just how many ETs does that end up being?

Click to enlarge.

This BBC infographic by Information is Beautiful does two pretty brilliant things. First, it reinterprets the Drake Equation as a colorful series of triangles rather than an esoteric math equation. Secondly, it builds its own calculator into this graphic, meaning you can fill in various values to easily see how they’d impact our ability to spot other intelligent life in our galaxy. Yes, it’s an infographic that you can actually tweak, one that doesn’t promise answers as much as it does more questions.

So what’s the magic number? How many alien species are there in the Milky Way? Well, that depends on your own assumptions of a lot of variables. But my skeptical nature, which argues that most intelligent life will either destroy itself or go into hiding (meaning each species only transmits data to other planets for about 2,000 years rather than a few million), would mean that we should be able to spot over 11,000 alien species in our galaxy alone and another 1.5 billion or so in the universe at whole. Crazy. Within the Milky Way, that’s one whole intelligent alien civilization for every 4.6 people on earth.

So if we knew all intelligent life in our galaxy, over a quarter of the entire human race would be dedicated to diplomacy. That’s a whole lot of new jobs you can create, NASA!

[Image: Alien Position via Shutterstock]

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  • Gracie B

    According to the BBC, this infographic is "not accessible from the UK as it is part of our international service and is not funded by the licence fee."

    Can anyone explain the logic behind this position? Or did all visitors to the site from outside the UK chip in a couple of bucks before being shown the goodies?

  • BetaSve

    Interestingly nobody speaks of the frames in time. As per 13bn years of existence, there could be civilizations that are long gone (but still included in that count). I mean it is not for sure that we are not the only civilization in the galaxy today...

  • Vongsawat Wongkijjalerd

     The rate of star formation per year (the R factor) takes this in to account. Running it through the equation except for the last variable (L) you get the number of communicable civilizations that form per year, then multiply that by the length of time that each civilization would exist and communicate (L) you get how many of these civilizations would exist on average at any one time.

    (yea, it bugged me too, a quick wiki search solved that quite easily =p)

  • Ann

    The typography can be improved - there are a lot of widows in this layout. It is important to prioritize readability when visualizing information.