This is how the Earth go’s around the Sun and changes seasons. In about 5 billion years the Sun will expand it self and swallow up the Earth. Seasons change because the axis of the earth is tilted by 23.5 degrees(from a line perpendicular to its orbit.).
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This is how the Earth go’s around the Sun and changes seasons. In about 5 billion years the Sun will expand it self and swallow up the Earth.
Seasons change because the axis of the earth is tilted by 23.5 degrees(from a line perpendicular to its orbit.)
As the Earth moves around its orbit there is a time when it is tilted towards the sun and so receives a higher concentration of the suns energy (summer) and a time when it is tilted away receiving less energy (winter).
If you think of the sun’s age as the length of a 24-hour day, then humans have only been around for a
Stars are born within huge clouds of hydrogen gas and dust particles called nebulas. Over many years, gravity crushes the particles together they until they heat up and begin to glow. When the gas gets hot enough, it sets off a nuclear explosion and a new star is born. Stars are usually born by the dozen within a nebula.
The life of a star depends upon how it big is. The smaller the star is at birth, the longer it will live. Very small stars can live for hundreds of billion of years while very large stars may live for only a few million years.
When a star begins to run out of fuel, the centre of the star shrinks and the outer parts of the star expands star become a red giant or supergiant. All main sequence stars eventually become red giants or supergiant's. However what happen next depend on the mass of the star's as Exploring the Live of Stars shows. When a star run out of fuel, it becomes a White Dwarf, a Neutron Star, or a Black Hole.