Astronomers think planets formed from interstellar dust and gases that clumped together in a process called _____.
1.stellar evolution
2.nebular aggregation
3.planetary accretion
4.nuclear fusion
Now you can reason this one out.
We are talking about planets
Not stars (stellar)
Not nebula
not fusion
so ----
If you have a good dictionary and look these words up, you'll find the answer.
Sra
The correct answer is 3. planetary accretion.
Astronomers believe that planets formed through a process called planetary accretion. This process involves the clumping together of interstellar dust and gases in a rotating disk around a young star, known as a protoplanetary disk or a circumstellar disk.
To arrive at this answer, we can eliminate the other options.
1. Stellar evolution refers to the life cycle of a star, including its formation, nuclear fusion, and eventual death. While stellar evolution is involved in the formation of stars, it is not the process that leads to the formation of planets.
2. Nebular aggregation is not a recognized scientific term. However, the concept of "nebular hypothesis" refers to the formation of the solar system from a rotating cloud of gas and dust, which is similar to planetary accretion.
4. Nuclear fusion is the process by which stars generate energy in their cores by fusing hydrogen atoms to form helium. It is not directly related to the formation of planets.
Therefore, the correct answer is 3. planetary accretion.