Astronomy Certification Questions and CORRECT Answers

8. How is a nova different from a type Ia supernova? How does it differ from a type II supernova? - A nova is a smaller energy explosion on the surface of a white dwarf in a close binary system, where fresh material from a donor star is deposited on the surface of the white dwarf until it ignites. A type Ia supernova has a similar configuration, but in this case, the material deposited on the surface of the white dwarf is sufficient to push the white dwarf past the Chandresekhar limit. Once that happens, the white dwarf will collapse and then explode into a type Ia supernova. A type II supernova does not involve a white dwarf but instead requires a massive star to reach the end of its ability to generate energy in its core. This results in a collapse of the core and an explosion into a type II supernova. 18. Suppose no stars more massive than about 2 MSun had ever formed. Would life as we know it have been able to develop? Why or why not? - Stars with masses less than two times the mass of the Sun can produce elements only up to carbon and oxygen. More massive elements are not produced, and some of these more massive elements (phosphorus, calcium, silicon, iron) are essential for the forms of life found on Earth