Jeopardy! category: TO THE EXOPLANETS! (21-05-2014)
$1200 clue: The first Earth-size exoplanets were found by the NASA satellite launched in 2009 & named for this 17th c. German astronomer
The gist: It’s a bit anthropomorphic to say that the telescope found the exoplanets – surely credit should go to the scientists who used its data.
But regardless, without the telescope named for Johannes Kepler, we still might not know that there are any planets orbiting other stars. The number of times Kepler’s been mentioned already in discussions of clues from this category should hint at its importance – so far, Kepler’s data has allowed astronomers to confirm the location of (at current count) a whopping 962 exoplanets in 76 star systems, along with 2903 more possible candidates.
The Kepler telescope was launched on March 7, 2009, with the purpose of finding Earthlike planets in other star systems. It packs a telescope with a 1.4 metre mirror feeding an 0.95 m aperture, which is able to continuously monitor 145 000 stars in its fixed field of view, as well as a 95 megapixel camera and lots of other technical bits. Although it’s run into a bit of mechanical trouble with two of its reaction wheels, the telescope should be able to continue hunting for planets relatively unabated, thanks in particular to NASA’s new K2 program.
As for the astronomer, Johannes Kepler was born in Germany (then part of the Holy Roman Empire) in 1571, and became the preeminent astronomer of his age. He became Tycho Brahe‘s assistant and eventually the court astronomer of Rudolf II in Prague. Kepler’s most famous contribution to astronomy are his laws of planetary motion, which posited that (a) planetary orbits are elliptical, (b) a line joining the sun and a planet covers an equal area in an equal amount of time regardless of the planet’s position, and (c) the distance of a planet from the sun is proportional to the semi-major axis of its orbits. As if these extremely influential theories (which turned out to be pretty much spot-on) weren’t enough for a big telescope to be named after him, he also did work directly on telescopes in his own day.
The clue: Johannes Kepler is definitely the most famous German astronomer of the 17th century (Copernicus and Brahe are both mainly 16th century; Galileo is Italian), so that should be a dead giveaway to a contestant who knows their astronomers. If you aren’t quite sure about Johannes’ situation in time and space (pun intended, har har), the exoplanet telescope is an added hint, in case you keep up with astronomical news.
In Jeopardy!: Kepler appears in about 40 regular clues and two FJ! clues in the J!Archive. His laws appear in 13 clues and “planetary motion” in 11. His nationality is in a whopping 14. Both Brahe and ellipses appear in eight. The telescope/satellite named for him, on the other hand, only appears in three. Certainly that’s because the telescope is only five years old, and we will probably see more clues about it as time goes on, but for now the man himself is more important. And there’s plenty to know about him, although the five things mentioned above should cover you for most of it.