set of problems

Demon core, a spherical subcritical mass of plutonium manufactured during World War II by the United States as a fissile core for an early atomic bomb

赤外線天文学: infrared astronomy

花一匁: a traditional Japanese children's game that is similar to the game red rover

astronomer

Alternative spelling of 花一匁

(astronomy) radio astronomy

a traditional Japanese children's game that is similar to the game red rover

Montgomery (a city, the capital city of Alabama) / Montgomery (a city in Texas) / Montgomery (a town in Powys, Wales)

astronomical (relating to astronomy) / astronomical (vast)