160 Billion Planets In The Milky Way | Out Of This World Weekly

I hope that you like big numbers because researchers have estimated the number of planets in our own galaxy at 160 Billion. This recent estimation uses Gravitational Microlensing, which has recently been used to find planets that aren’t even orbiting stars. This estimate is based on an estimation of 100 Billion stars in the Milky Way, thus each star that you see in the sky on average has 1.6 planets orbiting it. The previous estimate was 0.5 planets per star, more than tripling the amount of estimated planets.


Yes, this estimate means that there are more planets than stars in the sky. So, how many stars are in the sky? It’s estimated that there are about 10 sextillion to 1 septillion stars (that’s 10,000,000,000,000,000,000,000 to 1,000,000,000,000,000,000,000,000 stars) in the universe, with on average more than one planet orbiting it. That’s many more than the absolute limit of 9 planets that I learned about in middle school. This has dramatic effects on the Drake equation, which is used to calculate the amount of habitable planets, alien life, and alien civilizations.

There have been other recent discoveries that may hint at an even higher number. Several planets have been found orbiting binary stars. Binary or Double Stars were thought to be far too chaotic for a planet to form or if a planet did form it would soon be torn apart by gravitational forces. This has been proven wrong by recent discoveries of several Binary Stars with planets. Planets are also being found around other stars that are smaller and smaller. This week a planet with 0.57 times the Earth’s mass was found orbiting a star 130 light years away – which is about the size of Mars. As we find stars with a higher number of small planets, that will also increase the number of the total number of suspected planets in the universe.

While these huge numbers of planets possibly make our planet less special, they also show that we will find other places to live in the Milky Way Galaxy. This is extremely important as people will inevitably need to leave this planet at some point. The more places we have to live in the galaxy, the better chance that our species will survive in the long term.

1 comment :

  1. I love the album Drake Equation by Tub Ring!

    Err... Sorry. Been reading too many YouTube comments.

    Bite the Wax Tadpole 4evar!

    ReplyDelete