Table of Contents
- 1 How can scientists use elements to determine the age of a star?
- 2 How can we best tell the age of a star cluster?
- 3 How do scientists know how far away a star is?
- 4 How do you identify a star cluster?
- 5 How do we know what stars are made of we determine the composition of stars through quizlet?
- 6 How do you read stars?
How can scientists use elements to determine the age of a star?
Scientists can look at the spectra of a star and tell its temperature, which is related to the size, etc. In turn, this information reveals how much hydrogen or helium is left inside the star. We know the rate at which stars burn the gases. Scientists can now tell how old the star is depending on its composition!
How can we best tell the age of a star cluster?
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.
Can you tell the age of a star by its color?
As stars age, they run out of hydrogen to burn, decreasing the amount of energy they emit. Thus, younger stars can appear bluer while older ones appear more red, and in this way, a star’s color can tell us something about that star’s age.
How do we know what we know about the stars?
How do astronomers know what stars are made of when those stars are light years away from Earth? By comparing the absorption lines of the sun with emission spectra of known gasses, the chemical composition of stars can be determined.
How do scientists know how far away a star is?
Astronomers estimate the distance of nearby objects in space by using a method called stellar parallax, or trigonometric parallax. Simply put, they measure a star’s apparent movement against the background of more distant stars as Earth revolves around the sun.
How do you identify a star cluster?
Two main types of star clusters can be distinguished: globular clusters are tight groups of hundreds to millions of old stars which are gravitationally bound, while open clusters are more loosely clustered groups of stars, generally containing fewer than a few hundred members, and are often very young.
How can you estimate the age of a star cluster quizlet?
because all of a clusters’s stars were born at the same time, we can measure a cluster’s age by finding the main-sequence turnoff point on an H-R diagram of its stars. The cluster’s age is equal to the hydrogen-fusion lifetime of the hottest, most luminous stars that remain on the main sequence.
How do scientists determine the age of galaxies?
Astronomers estimate the age of the universe in two ways: 1) by looking for the oldest stars; and 2) by measuring the rate of expansion of the universe and extrapolating back to the Big Bang; just as crime detectives can trace the origin of a bullet from the holes in a wall.
How do we know what stars are made of we determine the composition of stars through quizlet?
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How do you read stars?
Stars are represented as black dots on a white background, which makes it easier to read when observing at night. The size of the dot reflects the brightness of the star, the bigger the dot, the brighter the star. In addition to dots, there are gray circles that refer to star clusters and ovals to galaxies.