He has a deep interest in astronomy.

Radio astronomy plays a very important role in understanding the universe.

Infrared astronomy provides a new perspective on understanding the universe.

If you plant this seed, beautiful flowers will bloom.

In astronomy, a blazar is described as a type of very active galaxy.

His activity surprised all of us.

She is a very active person.

He gave me a detailed explanation of the problem.

He explained the problem.

It is a very beautiful view.