Question

If we begin from star birth, the next key stage in the star-gas-star cycle occurs when a(n)_______ returns gas and new elements into space. The expelled gas forms a(n)________ that is very hot and expands in size. As the gas cools and merges with other interstellar gas, it forms a(n)__________ . Further cooling allows the gas to become a(n)_________ , in which star formation occur.

Answer 1

1. A Supernova

2. A Bubble

3. Atomic hydrogen cloud

4. Molecular cloud

Step-by-step explanation:

If we begin from star birth, the next key stage in the star-gas-star cycle occurs when a Supernova returns gas and new elements into space. The expelled gas forms a Bubble that is very hot and expands in size. As the gas cools and merges with other interstellar gas, it forms an Atomic hydrogen cloud. Further cooling allows the gas to become a Molecular cloud, in which star formation occur.

Answer 2

1. supernova

2. bubble

3. atomic hydrogen cloud

4. molecular cloud

Step-by-step explanation:

Supernova involves the bright explosion of a star when this happens it returns gas and new elements in to space. The expelled hot gas from the explosion forms a bubble and starts expanding in size. As this bubble cools, it merges merges with other interstellar gas to form an atomic hydrogen cloud. The atomic hydrogen cloud cools further to form a molecular cloud where another star formation begins to occur.