How do scientist calculate the age of the stars and planets?

Question

Some articles listed the estimated age of the sun and planets surrounding it.

I am just wondering, what technology do they use to do that calculations? Is it Gamma rays or I don't know, some other technology?

Answer 1

As a star evolves, its surface temperature and its brightness change in a well-understood way. Astronomers can determine the ages of certain stars by measuring their temperature and brightness, then performing calculations based on their knowledge of stellar evolution. By means of such techniques, astronomers have found stars that may be about 13 billion years old -- but no stars that are clearly older than that.

Radioactive dating of stars is based on the fact that certain chemical elements undergo radioactive decay. In radioactive decay, an isotope (form) of an element turns into an isotope of another element. Radioactive isotopes decay at known rates.

In 2001, scientists working with the European Southern Observatory's Very Large Telescope in Chile applied the radioactive dating technique to an old star in our galaxy, the Milky Way. The researchers studied the isotope uranium 238, whose nucleus contains 92 protons and 146 neutrons. The scientists knew how much uranium the star must have had when it formed, and they measured how much it has now. They then applied their knowledge of decay rates to calculate the age of the star. The most likely age of the star is 12.5 billion years, so the universe is probably older than that. Measurements of the ages of many old stars using another element, thorium, gave similar results

Answer 2

The age of the sun is roughly calculated by the percentage of chemicals inside it. Hydrogen is the primary nuclear fusion fuel of a star for most of its life. As it is consumed via the fusion process, Hydrogen it is converted to helium.

By measuring the amount of hydrogen relative to helium, and other elements a rough idea of how long the star has been burning can be found.

I believe this is measured through a method called spectroscopy, where a beam of light from the star is split by something like a prism. The lines that form from that split can tell the stars chemical composition.

The age of planets is more difficult to determine, because the theories of planetary formation are not yet well proven. Most of it is still a mystery.

The age of the moon has been roughly determined by moon rocks samples, and radioactive carbon dating. In addition, pictures of the craters on the moon show roughly how old they are, since new craters damage older craters.

There is still a lot to learn.

Answer 3

Age On Planets

Answer 4

Its very simple i think you havent studied science.

Astronomers can determine the mass, age, chemical composition and many other properties of a star by observing its spectrum, luminosity and motion through space.
A plot of the temperature of many stars against their luminosities, known as a Hertzsprung-Russell diagram (H-R diagram), allows the current age and evolutionary state of a particular star to be determined.

Many stars are between 1 billion and 10 billion years old. Some stars may even be close to 13.7 billion years old — the observed age of the universe.[45] (See Big Bang theory and stellar evolution.) The more massive the star, the shorter its lifespan, primarily because massive stars have greater pressure on their cores, causing them to burn hydrogen more rapidly. The most massive stars last an average of about one million years, while stars of minimum mass (red dwarfs) burn their fuel very slowly and last tens to hundreds of billions of years.

Answer 5

Those are estimates. For a star, its size temperature and spectrum can give you a clue. The age of a planet will be tied to the age of it's star.

Answer 6

there is something called the "H-R DIAGRAM." generally, the color is an approximation of age. also, older stars develop heavier elements in the hydrogen fusion liberation. at the beginning of fusion, helium is the 'ash' of hydrogen fusion and as time progresses the elements become heavier.
look up H-R DIAGRAM the story of the diagram itself is quite interesting, especially that it was concieved by two people at about the same time.
additionally, from observation of the light liberated by stars, the light is broken down into "line spectra" of dark and light lines. many things can be determined from the light spectra.

Answer 7

From what I remember its the chemicals in the star to determine how old it is and the color of the rays it gives off. I think but I am not sure.

Answer 8

Most aging calculations are based on exponential decay rate of energy.

Answer 9

stars are basically big fusion reactors. as they get older, among other characteristics such as brightness and temperature, the elemental composition of the star changes. the elements present in the star can be detected based upon their line absorption spectra.

Answer 10

they work it out from the temperature and luminosity.
as the star gets older it has more helium and less hydrogen so it makes its energy differently.