Q:

How many suns are there?

A:

Quick Answer

Earth's solar system has only one sun, but if the word "sun" is taken to mean "any star with planets in orbit," the Milky Way might have as many as 400 billion suns. If the observed ratio of approximately one planet per star is consistent everywhere, the observable universe might contain 10^24, or 1 septillion, suns.

Continue Reading

Full Answer

The sun of Earth's solar system is large when compared with other planet-supporting stars. Of the 50 stars within 17 light-years of the solar system, the sun is the fourth most massive. The majority of stars that last long enough to support the formation of planets are classified as red dwarfs. These stars are smaller and less massive than the sun, they burn through their smaller complements of hydrogen fuel more slowly, and they shine much longer than stars like the sun.

Very large stars, such as the blue giants, tend not to support planetary systems. These stars' high mass drives accelerated fusion reactions in their cores and exhausts their entire complement of hydrogen on a scale of tens of millions of years as compared to billions of years for stars like the sun, which might not allow time for planetary systems to form. However red dwarfs could potentially endure for trillions of years and form full planetary systems.

Learn more about Our Sun

Related Questions

  • Q:

    What is Europa's distance from the sun?

    A:

    Europa is one of Jupiter's four large moons, and its distance from the sun is always the same as Jupiter's, plus or minus the radius of Europa's orbit. Depending upon its position in orbit, Europa is 779.4 million to 780.6 million kilometers from the sun.

    Full Answer >
    Filed Under:
  • Q:

    What is an explanation for children about how the Earth orbits the sun?

    A:

    The Earth's orbit around the sun is controlled by two things. The first is the gravity of the sun, and the second is the way the earth moves sideways in space.

    Full Answer >
    Filed Under:
  • Q:

    Why is the sun important?

    A:

    Humans, animals and plants on Earth need the sun because it provides most of the energy required to survive in this solar system. Earth would be a very cold and lifeless planet if it did not get its light and heat from the sun. Similarly, the Earth's stays in orbit because of the gravitational pull of the sun.

    Full Answer >
    Filed Under:
  • Q:

    What size is the sun?

    A:

    The sun has a radius of about 432,450 miles and a diameter of about 864,938 miles and is the largest object in the solar system. The sun's circumference measures approximately 2.7 million miles.

    Full Answer >
    Filed Under:

Explore