Type Ia supernova

Definition

A type Ia supernova is a stellar explosion resulting from the complete disruption of a white dwarf in a binary system. It occurs when the white dwarf gains enough mass from its companion to reach the Chandrasekhar limit, leading to a runaway nuclear fusion reaction.

5 Must Know Facts For Your Next Test

1. Type Ia supernovae are used as standard candles to measure astronomical distances.
2. They result from white dwarfs in binary systems accreting matter from their companions.
3. The Chandrasekhar limit, approximately 1.4 solar masses, is critical for triggering these explosions.
4. Type Ia supernovae produce a consistent peak brightness due to similar mass and composition at explosion.
5. They play a crucial role in understanding the accelerating expansion of the universe.

Review Questions

• What triggers a type Ia supernova?
• Why are type Ia supernovae considered standard candles in astronomy?
• What is the significance of the Chandrasekhar limit in the context of type Ia supernovae?

Related terms

White Dwarf:

A small, dense star that remains after a low or medium mass star has exhausted its nuclear fuel.

Chandrasekhar Limit:

The maximum mass (approximately 1.4 solar masses) that a stable white dwarf can have before collapsing.

Standard Candle:

An astronomical object with known luminosity used to measure distances in space.