When fusion in low-mass stars form this element in its core, the helium flash stage begins.

When an iron core is reached gravity takes over and a(n) _________ occurs.

Supernovas are one of the largest _______ in the Universe.

Almost all stars form from nebulae at about the same time in _____.

_____ stars evolve and move off the main-sequence first; then intermediate stars & so on.

The dividing line between high & low-mass stellar evolution is called the

Since stars are born in clusters, these stars will have evolved off the main sequence first.

The Roche Lobe describes the region of space surrounding a _____.

Stars that orbit close to each other can overflow their Roche lobes to form a ______

Close binary star systems that share stellar material can affect how each star _____.

Alcor & Mizar are two stars in the "Big Dipper" (Ursa Major) that are _____ binaries.

Supernova explosions always occur when a high-mass star uses up fuel at its core.

For a sun-like star on the main sequence, change will gradually occur as it evolves.

Earth-like planets may exist in abundance around binary star systems.

All elements heavier than carbon were formed in supernova explosions.

Low-mass stars like our Sun will never explode.