if our sun was bigger what would hapen when the hydrogen was used up?

Question

hello please can someone help me eith this physics question thanks

Answer 1

If the Sun had twice it's present mass, it would give off 26 times the Sun's present output, if not more. A 2.5 solar mass star gives off 60 times more energy than the sun, and a 6 solar mass star can outshine the Sun 1,000 times over. There are stars that have more than 25 solar masses that emit as much light as 100,000 Sun like stars put together. Depending on the exact mass, it will burn hotter, brighter and exhaust it's hydrogen fuel much sooner. A 2 or 2.5 solar mass star like Sirius or Vega has at best a billion years worth of hydrogen in it's core before it starts to expand into a red giant. Therefore the Sun would have long since gone though it's red giant and supergiant phases, puffed out a planetary nebula and the remaining core would now be a white dwarf. In simple terminology, a star more massive than the Sun lives it's life in the fast lane and dies young. It would also expand into a bigger red giant than it otherwise would have, and Earth along with Venus and Mercury would after losing their atmospheres to a super powerful stellar wind and their surfaces being turned into an ocean of lava, would spiral into the Sun to their incineration. If the Sun had 8 or more times it's present mass, when it runs out of fuel it will explode as a core-collapse supernova, and that would either incinerate it's planets or hurl them into space. If the Sun had 25 times it's present mass, it would have not only exploded as a supernova long ago, it could do so without ever becomming a red giant or supergiant because these stars apparently can fuse hydrogen and helium in their cores simultaneously. Once carbon fusion starts, such a star can last only for a few hundred years before the core implodes into a neutron star or a black hole and the rest of the star is either sucked in or blasted back into space.

Answer 2

No, the better way to phrase it is: When the hydrogen gets used up the Sun will then get bigger.
The mutual gravitational attraction of all the atoms in the Sun are trying to pull themselves together into the same spot. Right now, the Sun is turning approx 600 million tons of Hydrogen into Helium every second through the process of nuclear fusion. The energy released from this process expands the surface to its present size and gives the Sun its yellow color. When all the Hydrogen is used up, fusion will stop, all the leftover Helium [and some other elements] will collapse due to gravity until Helium fusion begins. Then the Sun will turn into a Red Giant whose surface will be somewhere between the current orbits of Earth and Mars.

Answer 3

Indian physicist Subrahmanyan Chandrasekhar discovered that any star greater than 1.44 solar masses is likely to end its life as a supernova. So the Sun will end its "lifetime" on the main sequence in the form of a nova. In a few billion years, the Sun will swell to a size great enough to engulf the inner planets, including the Earth. Then at some point, it will shed its outer layers of gas that will expand into a bubble many times larger than the solar system.

So if your hypothetical sun was above the Chandrasekhar Limit, it would end in a violent explosion that would be visible from 1000s of light years away.

Answer 4

It depends on how *much* bigger. If the sun had at least 1.5 times more mass than it does, it could explode in what's called a 'supernova' when it finally used up all its fuel, like hydrogen. If the sun had about 3 times more mass it not only would explode as a supernova, but probably end up as either a neutron star or a black hole.

Answer 5

Hi. A bigger (more massive) Sun would fuse hydrogen at a faster rate. When the hydrogen was gone there would be a helium 'pop' as helium was pressured into fusion. Eventually the Sun would explode.

Answer 6

if the sun was bigger than it is now and the hydrogen was used up, the sun would swell up to the size of a red giant star, and then explode in a massive supernovea.
if the sun was really much bigger than that, then it would end up as a neutron star, a pulsar or a black hole.

Answer 7

Hertzsprung-Russell diagram. Yellow low-mass stars like the sun bloat when heavy element fusion starts, blow off their surface, and end up as white dwarfs (oxygen and carbon stars, etc.) More massive stars go supernova.

Answer 8

As the hydrogen is used up, and the sun looses it's density, the gravitational pull will be less, causing our planet earth and all other planets to drift away from the sun and become arctic and inhabitable.

Scary thought

Answer 9

we would be gone, thank god it's not.

Answer 10

boom. Big explosion my dear