He is an expert in planetary science.

Pluto is classified as a dwarf planet.

He was reading a book about the ancient Egyptian sun god.

The sunlight is illuminating the room brightly.

When the sun rises, a new day begins.

Solar wind affects the Earth's magnetic field.

The service life of this machine is 10 years.

We calculate time using the solar calendar.

The heliocentric theory is the idea that the sun, not the earth, is the center of the universe.

We installed solar batteries on the roof of our house.