Albedo, bolide, constellation,
dichotomy, eclipse, first point of Aries,
great circle, Hertzsprung-Russell, inferior planet,
Julian date, kiloparsec, limb darkening,
Maunder minimum, node (descending), occultation,
proper motion, quadrature, retrograde,
synodic period, Titus-Bode law, universal time,
Viking lander, waning gibbous, x-ray source,
young moon, Zubenelgenubi and -- oh yes --
Begin with wonder. Lying on one's back, perhaps, under a dark canopy of stars. Head empty, except for awe. A sense of enormous depth and enormous mystery.
Wonder is a private emotion. But wonder leads to wondering, and wondering leads to knowledge. Reliable, public knowledge.
For that we can be grateful to generations of curious minds who submitted their investigations to the test of reproducible observation.
Begin with naming. Zubenelgenubi, the southern claw of the Scorpion. Zubeneshamali, the northern claw. With Hipparchus, add numbers. Zubenelgenubi is a 3rd magnitude star; Zubeneshamali is a 4th magnitude star. Add color, then temperature. Then distance. Eventually arrive at the x-ray source at the center of the galaxy powered by a black hole with a mass of millions of suns.
Hipparchus. Aristarchus. Claudius Ptolemy. Copernicus, Tycho and Kepler. Bruno and Galileo. Titus and Bode, Hertzsprung and Russell. The Herschels -- William, Caroline and John. Maria Mitchell and Henrietta Leavitt. Shapley and Hubble. Subrahmanyan Chandrasekhar and Jocelyn Bell. An endless parade of unfettered curiosity. One test and one test only -- exact, quantitative, reproducible data.
On my back on the terrace. The sky awash with stars. Wonder. And knowledge too.