Question

What would you need to measure about a planetary nebula (see the image below) to determine how long ago its parent star died?

Answer 1

To determine the age of a planetary nebula, we can use the equation distance = velocity x time. By converting the diameter of the nebula to miles and dividing it by the velocity, we can calculate the time it took for the gas to leave the star. In this case, the gas left the star approximately 5.97 million years ago.

Step-by-step explanation:

To determine how long ago the parent star of a planetary nebula died, we can use the equation distance = velocity x time. In this case, we are given that the gas is expanding away from the star at a rate of 25 mi/s and the diameter of the nebula is 0.8 light-year.

We can convert the diameter to miles by multiplying it by the speed of light. Then, we can divide the distance by the velocity to find the time.

To calculate the time, we follow these steps:

1. Convert the diameter of the nebula to miles: 0.8 light-year x 5.88 trillion miles/light-year = 4.704 trillion miles
2. Divide the distance by the velocity: 4.704 trillion miles ÷ 25 mi/s = 188.16 billion seconds
3. Convert seconds to years: 188.16 billion seconds ÷ 31,536,000 seconds/year = 5.97 million years