HR Digram

The stars that are blue are the hottest, the stars that are red are the coldest. Hotter stars have shorter lives

1. On an H-R Diagram, what is the main sequence?

Main-sequence stars are stars that fall along a band that runs from the upper left corner to the lower right corner of the diagram.

2. What percentage of stars are main sequence stars?

90% of stars are main sequence stars

3. Is the Sun a main sequence star?

The sun is a main sequence star.

4. What will happen to the Sun next? When will this happen?

In 4 to 5 billion years the sun will turn into a red giant.