How old is are sun

That had to wait 50 years for Isaac Newton to discover the universal law of gravitation. Closer planets revolve faster, more distant planets revolve slower. The answer lies in how gravity works. The force of gravity is a measure of the pull between two bodies. This force depends on a few things. First, it depends on the mass of the sun and on the mass of the planet you are considering. The heavier the planet, the stronger the pull. If you double the planet's mass, gravity pulls twice as hard.

On the other hand, the farther the planet is from the sun, the weaker the pull between the two. The force gets weaker quite rapidly. If you double the distance, the force is one-fourth. If you triple the separation, the force drops to one-ninth. Ten times the distance, one-hundredth the force. See the pattern? The force drops off with the square of the distance.

If we put this into an equation it would look like this:. The Exploratorium is more than a museum. Explore our online resources for learning at home. Travel to an outer planet! Johannes Kepler. So our Sun is about halfway through its life. It still has about 5,,,—five billion—years to go. When those five billion years are up, the Sun will become a red giant. That means the Sun will get bigger and cooler at the same time. When that happens, it will be different than the Sun we know today.

As a red giant, our Sun will become about 2, times brighter than it is now! How Old Is the Sun? Is it really old? Or not so much? The surface of the sun is about 10, degrees Fahrenheit 5, degrees Celsius hot, while temperatures in the core reach more than 27 million F 15 million C , driven by nuclear reactions.

One would need to explode billion tons of dynamite every second to match the energy produced by the sun, according to NASA. The sun is one of more than billion stars in the Milky Way. It orbits some 25, light-years from the galactic core, completing a revolution once every million years or so.

The sun is relatively young, part of a generation of stars known as Population I, which are relatively rich in elements heavier than helium. An older generation of stars is called Population II, and an earlier generation of Population III may have existed, although no members of this generation are known yet. Related: How hot is the sun? The sun was born about 4.

Many scientists think the sun and the rest of the solar system formed from a giant, rotating cloud of gas and dust known as the solar nebula.

As the nebula collapsed because of its gravity, it spun faster and flattened into a disk. Most of the material was pulled toward the center to form the sun. Related: How was the sun formed? The sun has enough nuclear fuel to stay much as it is now for another 5 billion years.

After that, it will swell to become a red giant. Eventually, it will shed its outer layers, and the remaining core will collapse to become a white dwarf. Slowly, the white dwarf will fade, and will enter its final phase as a dim, cool theoretical object sometimes known as a black dwarf. Related: When will the sun die? The sun and the atmosphere of the sun are divided into several zones and layers. The solar interior, from the inside out, is made up of the core, radiative zone and the convective zone.

The solar atmosphere above that consists of the photosphere, chromosphere, a transition region and the corona. Beyond that is the solar wind , an outflow of gas from the corona. The core extends from the sun's center to about a quarter of the way to its surface. Light from the core gets scattered in this zone, so that a single photon often may take a million years to pass through.

Roiling "convection cells" of gas dominate this zone.