He always feels like a spirit is following him.

It is said that a wandering spirit appears in that old house.

She has the ability to see spirits.

He said he could see spirits.

He always feels at ease when he has a talisman.

The problem of space debris could potentially have a significant impact on future space development.

The study of cosmic rays may hold the key to unraveling the mysteries of the universe.

He proposed a new theory about cosmology.

He believes that aliens exist.

He is reading a book about space flight.