Table of Contents
- 1 Does the star Mira vary in brightness?
- 2 How does the star’s apparent brightness change over time?
- 3 Which group of stars ranges from cool and dim to hot and bright?
- 4 How much bigger is Mira than the Sun?
- 5 How many different stars are there?
- 6 Which is brighter a first magnitude star or a second magnitude star?
- 7 How does the color of a star depend on its mass?
Does the star Mira vary in brightness?
Bottom line: Mira is a variable star that undergoes periodic changes in brightness every 332 days, ranging from a maximum brightness of around 3.5 visual magnitudes to a minimum brightness of about 9 magnitudes.
How does the star’s apparent brightness change over time?
The apparent brightness of a star is proportional to 1 divided by its distance squared. That is, if you took a star and moved it twice as far away, it would appear 1/4 as bright; if you moved it four times the distance, it would appear 1/16 as bright. The reason this happens is simple.
Which group of stars ranges from cool and dim to hot and bright?
Supergiants — cool, bright, red, large stars • Giants — cool, bright red, less large stars • Main Sequence — spans range from hot, bright stars to cool, dim stars. White dwarfs — hot, small, dim stars.
How does a change in magnitude affect its brightness?
Every interval of one magnitude equates to a variation in brightness of 5√100 or roughly 2.512 times. Consequently, a magnitude 1 star is about 2.5 times brighter than a magnitude 2 star, about 2.52 times brighter than a magnitude 3 star, about 2.53 times brighter than a magnitude 4 star, and so on.
Is the Mira star a red giant?
Mira is a highly evolved, “red giant” star near the end of its life. Technically, it is called an asymptotic giant branch star. It is red in color and bloated; for example, if a red giant were to replace our sun, it would engulf everything out to the orbit of Mars.
How much bigger is Mira than the Sun?
Mira estimated radius has been calculated as being 8.35 times bigger than the Sun. The Sun’s radius is 695,800km, therefore the star’s radius is an estimated 5,810,500.93.km.
How many different stars are there?
Stars are classified by their spectra (the elements that they absorb) and their temperature. There are seven main types of stars. In order of decreasing temperature, O, B, A, F, G, K, and M….
| TYPE | Star |
|---|---|
| II | Luminous giants |
| III | Giants |
| IV | Subgiants |
| V | Main sequence stars (dwarf stars) |
Which is brighter a first magnitude star or a second magnitude star?
In other words, a first magnitude star was twice as bright as a second magnitude star. A star with apparent magnitude +3 was 8 (2x2x2) times brighter than a star with apparent magnitude +6.
What happens to a star when it becomes a red giant?
This newly generated heat temporarily counteracts the force of gravity, and the outer layers of the star are now pushed outward. The star expands to larger than it ever was during its lifetime — a few to about a hundred times bigger. The star has become a red giant. What happens next in the life of a star depends on its initial mass.
Which is the sixth brightest star in the sky?
It’s the sixth brightest star in Earth’s sky, not including our sun. Capella is a bright star, what astronomers call a 1st magnitude star. It’s one of the brightest stars in our sky.
How does the color of a star depend on its mass?
The color of the star depends on the surface temperature of the star. And its temperature depends, again, on how much gas and dust were accumulated during formation. The more mass a star starts out with, the brighter and hotter it will be.