Concept explainers
The distance between the stars in an open cluster and in a globular cluster.
Answer to Problem 3P
The distance between the stars in the open cluster ranges from 1.25 pc to 5.8 pc.
The distance between the stars in the globular cluster ranges from 0.015 pc to 0.11 pc.
Explanation of Solution
Calculation:
The volume of a Sphere is
The volume of a cluster of stars,
The volume of space between each star in an open cluster is the volume of the open cluster divide by the number of stars in the cluster, N .
Substitute the volume of the cluster in volume of star.
The distance between the stars, r is the radius of the sphere of empty space around each star.
Because there is a range of star numbers, there is a range of distances between the stars. To calculate the maximum space between the stars, use the smallest number of stars in the cluster.
An open cluster has a diameter of 25 pc and a minimum number of 10 stars.
To calculate the minimum space between the stars, use the largest number of stars in the cluster. The maximum number of stars in an open cluster is 1000 stars.
The distance between the stars in the open cluster ranges from 1.25 pc to 5.8 pc.
Global clusters have a range of diameters between 10 pc and 30 pc and contain between 100,000 and 1,000,000.
A globular cluster with the maximum space between the stars would have the largest diameter and the smallest number of stars.
A globular cluster with the minimum space between the stars would have the smallest diameter and the greatest number of stars.
The distance between the stars in the globular cluster ranges from 0.015 pc to 0.11 pc.
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Chapter 10 Solutions
Horizons: Exploring the Universe (MindTap Course List)
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- Stars that have masses approximately 0.8 times the mass of the Sun take about 18 billion years to turn into red giants. How does this compare to the current age of the universe? Would you expect to find a globular cluster with a main-sequence turnoff for stars of 0.8 solar mass or less? Why or why not?arrow_forwardIf all the stars in a cluster have nearly the same age, why are clusters useful in studying evolutionary effects (different stages in the lives of stars)?arrow_forwardWhy is star formation more likely to occur in cold molecular clouds than in regions where the temperature of the interstellar medium is several hundred thousand degrees?arrow_forward
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