Star

Eventually, the hydrogen that powers a star's nuclear reactions begins to run out. The star then enters the final phases of its lifetime. All stars will expand, cool and change colour to become a red giant or red supergiant. 

What happens next depends on how massive the star is.

All the energy in a star is made in its centre (its core), by a process called nuclear fusion. The star releases the energy as heat and light. This is what makes a star shine. The outward force generated by the fusion process is balanced by the inward pull of the star's gravity. It is the balance between the two which stops the star from collapsing or expanding.

Early Life

Claudius was born in Alexandria, Egypt, which was part of the Roman Empire at the time. 

Very little is known about his life. The information we do have has been taken from the books he wrote. 

Early Life

Cecilia was born in Wendover, England. Her mother was interested in lots of different topics like nature, music and theatre. Cecilia spent lots of time reading in her home's library.

At the age of 19, she won a scholarship to Cambridge University to study science. During that time, Cecilia went to a talk given by Arthur Eddington. Arthur talked about his recent trip to Africa to observe the stars near a solar eclipse. This sparked Cecilia's interest in astronomy.