A jaw-dropping video of all the 2299 currently discovered exoplanets and candidates, circling around one hypothetical star. This gives a good view of all the variation in size and orbit of currently discovered planets (including smaller, Earth-like ones).
This is pretty astonishing, if you remember that before 1988, no exoplanet had ever been discovered, and during the 1990s, only a few. But recent technological advances have made it possible to identify and confirm thousands of exoplanets – gas giants like Jupiter, but also Earth-like ones – only in the last couple of years. You can look them up in the Exoplanet Orbit Database or the Extrasolar Planets Encyclopedia.
As of 2012, 777 exoplanets in 623 planetary systems have been confirmed, and about 2300 are awaiting confirmation. It is estimated that more than 50% of Sun-like systems have planets (and planets have been discovered circling other types of stars as well). And of course, all of these have moons as well.
Yet, aside from on the internet, this facet of astronomy – unlike other big scientific projects of this era, such as CERN, the ISS and the Mars rover Curiosity – doesn’t get that much attention. Yet, NASA’s Kepler space telescope mission, searching for habitable planets, has done hugely important work, showing how even a small section of the universe is teeming with all kinds of objects.