2007-02-19 21:12:41 · 7 answers · asked by anoop bhargava 1 in Science & Mathematics ➔ Astronomy & Space
The Sun's current age, determined using computer models of stellar evolution and nucleocosmochronology, is thought to be about 4.57 billion years.
The Sun is about halfway through its main-sequence evolution, during which nuclear fusion reactions in its core fuse hydrogen into helium. Each second, more than 4 million tonnes of matter are converted into energy within the Sun's core, producing neutrinos and solar radiation. The Sun will spend a total of approximately 10 billion years as a main sequence star.
The Sun does not have enough mass to explode as a supernova. Instead, in 4-5 billion years, it will enter a red giant phase, its outer layers expanding as the hydrogen fuel in the core is consumed and the core contracts and heats up. Helium fusion will begin when the core temperature reaches around 100 MK, and will produce carbon and oxygen. While it is likely that the expansion of the outer layers of the Sun will reach the current position of Earth's orbit, recent research suggests that mass lost from the Sun earlier in its red giant phase will cause the Earth's orbit to move further out, preventing it from being engulfed. However, Earth's water will be boiled away and most of its atmosphere will escape into space.
Following the red giant phase, intense thermal pulsations will cause the Sun to throw off its outer layers, forming a planetary nebula. The only object that will remain after the outer layers are ejected is the extremely hot stellar core, which will slowly cool and fade as a white dwarf over many billions of years. This stellar evolution scenario is typical of low- to medium-mass stars.
2007-02-19 21:25:24 · answer #1 · answered by meezyfuh 1 · 1⤊ 0⤋
Sun has crossed five billion years mark in his age. Another five (exactly saying 4.57) billion years are left for Sun. After the completion of these years Sun will expand up to 10 times of his diameter and turn in to a red giant. After that stage, Sun turns into a White dwarf because the hydrogen in the Sun will exhaust. After that he will turn in to a neutron star and finally in to a black hole(?). Our Solar system will become merged in Sun at red giant stage. Thus the life of Sun and our solar system will end. Let us hope in future there would be another solar system like this and we all should born like this only and meet in Yahoo Answers....!
2007-02-21 01:15:43 · answer #2 · answered by ♥ ΛDIƬΥΛ ♥ ııllllııllıı 6 · 1⤊ 0⤋
life of the sun is estimated to be another more 7 billion years. by knowing the total amount of hydrogen converting into helium and the rate of nuclear fusion the age can be calculated.
2007-02-20 05:20:12 · answer #3 · answered by bhavya20002003 1 · 0⤊ 0⤋
The Sun's current age, determined using computer models of stellar evolution and nucleocosmochronology, is thought to be about 4.57 billion years
2007-02-20 06:47:48 · answer #4 · answered by Anonymous · 1⤊ 0⤋
the sun is a large hot gaseous body hydrogen and helium are the main gaseous.. in the core of the sun the temp is estimated to be about2,00,00,000 . according to the question the life of sun cannot be estimated..
2007-02-20 05:34:33 · answer #5 · answered by preeth r 1 · 0⤊ 0⤋
The sun is about 4.6 billion years old, and probably half-way through its life.
2007-02-22 23:32:36 · answer #6 · answered by skeetejacquelinelightersnumber7 5 · 0⤊ 0⤋
it had crossed its half of the age. it had to cross the remaining age which is equal to its present age.
2007-02-20 05:33:23 · answer #7 · answered by Raghavi 1 · 0⤊ 0⤋