- 1 How can astronomers measure the age of a star cluster quizlet?
- 2 How do astronomers know that globular clusters are old?
- 3 How do you measure a star’s lifespan?
- 4 How can astronomers use the HR diagram of a cluster of stars to determine their age?
- 5 What are two main types of star clusters?
- 6 What type of stars live the longest?
- 7 How many globular clusters are in the Milky Way?
- 8 What is the difference between open and globular star clusters?
- 9 What would it look like inside a globular cluster?
- 10 How long does a star stay in main sequence?
- 11 How long do M type stars live?
- 12 Why do massive stars have shorter lives?
- 13 Are older stars hotter?
- 14 Which types of stars are the oldest on the HR diagram?
- 15 What color is the coolest star?
How can astronomers measure the age of a star cluster quizlet?
How can astronomers measure the age of a star cluster? By determining which of their stars have already left the main sequence.
How do astronomers know that globular clusters are old?
How do astronomers know that globular clusters are very old? The turnoff point tells the astronomer the age of the star cluster. For an astronomer, what is the significance of the turnoff point in the Hertzsprung-Russell diagram of a star cluster? hundreds of thousands of members, all very old and generally metal-poor.
How do you measure a star’s lifespan?
To find the lifetime in years of a Main Sequence star, multiply the ratio of the star’s mass and luminosity in solar units times approximately 1010 years. or about 4.9 million years. or about 692 billion years, which is many times the age of the Universe.
How can astronomers use the HR diagram of a cluster of stars to determine their age?
By placing the stars in a globular cluster on a Hertzprung-Russell diagram, astronomers can determine the cluster’s age by looking at the main sequence turnoff point and comparing it with models of stellar evolution.
What are two main types of star clusters?
Star cluster, either of two general types of stellar assemblages held together by the mutual gravitational attraction of its members, which are physically related through common origin. The two types are open (formerly called galactic) clusters and globular clusters.
What type of stars live the longest?
The stars with the longest lifetimes are red dwarfs; some may be nearly as old as the universe itself.
- Red Dwarf Stars. Astronomers define a red dwarf as a star having between about 0.08 and 0.5 times the mass of the sun and formed primarily of hydrogen gas.
- Luminosity and Lifetime.
- Nuclear Fusion.
- Life Cycle of Stars.
How many globular clusters are in the Milky Way?
The Milky Way is surrounded by about 150 globular clusters, some of which are visible in the darkness of the night; but about ten or twenty thousand globular clusters can be found around the giant galaxies located at the centre of the galaxy clusters.
What is the difference between open and globular star clusters?
Globular star cluster are very symmetrical in shape, and are densest toward their centers. Open star clusters are more irregular in shape. Globular clusters orbit in the halo of our galaxy, centered on the galaxy’s center and expanding above and below the galactic disk. Open star clusters tend to orbit within the disk.
What would it look like inside a globular cluster?
In a typical position in a globular cluster (maybe halfway between center and edge), there’d be many more bright stars in the sky due to the star density. These would be distributed unevenly in the sky, with more light coming from the center of the globular cluster.
How long does a star stay in main sequence?
While the sun will spend about 10 billion years on the main sequence, a star 10 times as massive will stick around for only 20 million years. A red dwarf, which is half as massive as the sun, can last 80 to 100 billion years, which is far longer than the universe’s age of 13.8 billion years.
How long do M type stars live?
The lifetimes of main sequence stars therefore range from a million years for a 40 solar mass O-type star, to 560 billion years for a 0.2 solar mass M-type star.
Why do massive stars have shorter lives?
Stars shine because of nuclear fusion reactions in their core. Massive stars live shorter lives than the common small stars because even though they have a larger amount of hydrogen for nuclear reactions, their rate of consuming their fuel is very much greater.
Are older stars hotter?
The answer to this question goes like an intricate detective story. Scientists can deduce the age of a star by its brightness and color. stars, which in turn are brighter than red stars. are hotter are also brighter.
Which types of stars are the oldest on the HR diagram?
In the image above, you can see a schematic HR diagram with plots of lines that represent the Main Sequence for a number of open clusters. From the location of the Main Sequence Turn-Off, you can see that NGC 2362 is the youngest, then h & χ Persei, and M67 is the oldest of the clusters.
What color is the coolest star?
Red stars are the coolest. Yellow stars are hotter than red stars. White stars are hotter than red and yellow. Blue stars are the hottest stars of all.