The circumpolar star is always visible in the north.

Water training on the tatami is a traditional Japanese practice method.

In linear algebra, the upper triangular matrix plays a very important role.

Alpha Centauri, in the constellation of Centaurus, is the closest star to Earth.

He said, 'A nameless star comes out in the evening,' teaching me that achieving a goal is not easy.

A sub-brown dwarf is a celestial body between a planet and a brown dwarf.

Astrocytes are one of the important support cells in the brain.

My room is on the second floor, and your room is above mine.