How old is the Sun? What will happen when the Sun turns into a nebula?

The Sun was actually FORMED from a nebula over 4 and a half billion years ago. A nebula is a cloud of dust and gas. If enough of this dust and gas gather together, a star can form inside a nebula.

The Sun is now halfway through its life span. So in another 5 billion years, the Sun might begin to experience some changes. The Sun will expand to be several times its current size, becoming a red giant. Its effect on the terrestial planets will be devastating. The Sun will engulf Mercury, while Venus will probably orbit just outside the solar surface. The Earth will be scorched at this point, leaving the planet unsuitable for life. Pluto, in fact, would probably be the only planet suitable for any life in the solar system.

Because of its smallish size (compared with other stars), it is not likely that the Sun will undergo a supernova explosion. This type of explosion would create the aforementioned nebula. At the very end of its life cycle, the Sun will likely blow off only its outermost layers and shrink to the size of the Earth, becoming a cooler white dwarf star.

Submitted by Victor (age 14, Oregon, USA)
Submitted by Benjamin (age 9, Pennsylvania, USA)
(October 9, 1997)

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Last modified prior to September, 2000 by the Windows Team

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