I love planets, don’t you? Being all… round. With their… Atmospheres. Very gaseous. What’s not to love? Actually, as I’m writing this, there are 3449 confirmed planets in our galaxy. 544 of the planetary systems we’ve seen are multi-planet systems. And our galaxy is so vast, we’re barely even scratching the surface!
To give you some idea of the speed with which most of these planets have been discovered, here’s a nicely constructed animation, courtesy of exoplanet hunter Hugh Osborn, showing 300 years of planetary discoveries.
Unfortunately, the resized gif may make the text a little small, so click the image to see a glorious full size version. The different detection techniques are in different colours. Green are detections using the radial velocity method, red with transits, yellow through gravitational microlensing events, and the cyan points were found by direct imaging. The blue spots show the planets known in our own solar system. If you watch carefully near the lowest end of the mass scale, you’ll notice that this doesn’t stay constant – both Ceres and Pluto have been considered planets and then not planets at different points in history.
You may also notice that the final number on this image is 2954, not 3449. That’s because we’re discovering exoplanets so rapidly, it’s difficult to keep up. Turns out, all the sci-fi I used to enjoy as a kid was right. Our galaxy really is full of planets!
Pretty cool, huh?
Full credit for this image goes to Hugh Osborn.
So if you like it, then you should go and buy him shiny objects.