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Where are the stars during the day ?
| Date post: | 17-Jul-2015 |
| Category: |
Science |
| Upload: | noura-ishnawer |
| View: | 122 times |
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Where are the stars during the
day?
Andromeda is a huge group of stars in the shape of a disk. Andromeda is normally not visible close to city lights.
Sky report
Andromeda appears to be just a point of light. When you use a telescope to view Andromeda, it looks bigger and appears to be a fuzzy star.
What is a star?
Star is a giant ball of hot , glowing gases that release energy.
Light from stars takes time to reach Earth. Light travels 300,000 kilometers per second. That is fast!Light from the sun , a star, takes about eight and a half minutes to reach Earth.Light from other stars takes longer.
The distance light travels from stars is measured in light-years.
Light-year is the distance light travels in one year.
Alpha Centauri is the next nearest star to Earth. It is four light-years away from Earth.
Types of stars
All stars except the sun look like points of light because they are very far away. Some stars appear brighter than others.
Scientists use physical characteristics such as:
1- brightness2- size to describe stars.
3- color4-temperature
Stars can produce different amounts of light.The sun is a very bright star. The sun is the closest star to the Earth.
It may seem that bright stars in the night sky are closer to Earth than dim stars.
Actually, some stars that appear dim may be closer to Earth than bright stars.
bright star dim star
star`s distance from Earth is not the only reason it appears bright. Other features affect the brightness of stars besides its closeness to Earth.
Our sun and most stars in the universe are similar. However, stars can be different sizes.
The size of our sun is average.
Some stars are larger than our sun Spica Other stars are smaller BesselOver time, the size of a star can also change.
The star Spica is larger than our sun
Spica is about 260 light-years away from Earth
260
light-years
Spica looks like a point of light in the skySpica is two blue stars that are very close together
Bessel`s Star is smaller than our sun.
It is 11 light-years away from Earth.
11
light-years
Bessel`s Star is two stars that are very close. They both glow orange.
Stars have different temperatures and colors. A star can be
red
A star`s color is a result of its temperature. For example, blue stars such as Spica are hotter than orange stars such as Bessel`s Star.
Patterns of stars
Groups of stars can be found in distinct areas of the sky. Some groups of stars seem to make patterns or shapes.
The stars that make up these patterns look like they are close together in space. They really are very far apart. Some stars are farther from Earth than others.
If you look at the same stars from far away in space, they would not make the same pattern.
The patterns of stars you can see change with the seasons. As Earth moves around the sun, these patterns are in different parts of the sky.
Ursa Major, or the Big Bear is one of the patterns in the sky.
Within Ursa Major, you can see the Big Dipper. The Big Dipper looks like a cup with a handle.
The star Caph is one star that makes up the star pattern Cassiopeia.It is the brightest star in Cassiopeia.
Caph is 54 light-years from Earth and more than 25 times brighter than our sun.
Because of its distance from Earth, it looks like a paint of light.
The evolving universe
