Simplify the following text for a Grade 9 native English-speaking person.
Original: A total solar eclipse can be frightening to people who are unaware of their astronomical explanation , as the Sun seems to disappear during the day and the sky darkens in a matter of minutes .
Simplified: A total solar eclipse can frighten people who do not know what it means , because the Sun seems to disappear during the day and the sky turns dark in just a few minutes .