What caused the red giant phrase to begin in a main sequence star?

Answer 1

This is an easy one. When the sun grows, its performance is known as a red giant. The heat will wipe out any life on Mercury, Earth and Mars. The Moon is expected to float away into the vast darkness of the Universe. The red giant will appear in around 3billion years, so we have plenty of time to move out to a safe planet with all our good heat sources. The red giant is so big and full of gas that it cannot live any longer, and then the nebula will knock out all the planets except Pluto and beyond.

Answer 2

A star with a mass 8 - 10 times that of our sun uses up its fuel supply much more rapidly over a period of 30 million years and becomes a blue supergiant before further expanding to form a red supergiant

Answer 3

That is because the Sun will become much bigger. In total it will emit more radiation, but the amount of radiation per square meter will be less.

That is because the Sun will become much bigger. In total it will emit more radiation, but the amount of radiation per square meter will be less.

That is because the Sun will become much bigger. In total it will emit more radiation, but the amount of radiation per square meter will be less.

That is because the Sun will become much bigger. In total it will emit more radiation, but the amount of radiation per square meter will be less.

Answer 4

Basically this happens when a mid sized star has consumed most of the hydrogen fuel in it's core and the core begins to collapse. This collapse causes the layer of the star surrounding the core to heat up and causes the remaining hydrogen in that area to start fusing into helium.

This stage can cause the star to increase it's luminosity by a factor of 1 to 10 thousand! This causes the outer layers of the star to expand greatly so increasing the stars size. Even though more energy is being produced in this stage than in the main sequence the energy is now spread out of a much bigger area (due to the expansion) so the star 'looks' cooler (red). You now have a huge red star - a Red Giant.


The Red Giant phase of a star can be repeated a number of times - each time the star will fuse heavier and heavier elements until eventually the star will blow off the outer layers leaving just the core behind and the star will now be a White Dwarf.

Answer 5

A star (our Sun) spends its life in hydrostatic equilibrium [See related question] whilst it is on the main sequence.

When the Sun starts to run out of hydrogen, this equilibrium is severely unbalanced and the pressure envelope starts to expand, making the star larger and larger.

NB: It's worth noting that this is not a sudden occurrence, as the Sun is slowly getting larger and larger everyday because of the loss of mass in its core.

As the star gets larger, the temperature is spread out over a larger surface area, and thus appears cooler. Our Sun is yellow at the moment, but over time will become orange and then red, as it gets larger and larger and cooler and cooler.

In about 5 billion years - if you happened to view the Sun from Earth - which of course you wouldn't because all life would have died about 3 billion years before, a Sun rise would fill the horizon with "Sun".

Answer 6

The same way other stars form, except more so.

They are high mass stars that leave the "main sequence" when their core hydrogen is used up. They then develop into supergiant stars. There are several types, classified by colour (spectral type).

Answer 7

A red giant is a very old star. It is near death. It has depleted its hydrogen supply and is running on fumes, so to speak. Its outer layers are expanding while its core is contracting and will eventually explode and become a nebula or something of the sort. Here is a page with star classifications.

See the related link below.

Answer 8

Stars become red as the nuclear reactions in the core begin to change.

The star becomes red because throughout the star's lifetime, it has been using hydrogen to burn as fuel. As hydrogen burns an immense radiation pressure is built up which smashes and fuses hydrogen atoms together to form a heavier atom Helium. When the star burns up hydrogen it then burns Helium which burns less intensely as Hydrogen meaning the star cools slightly giving it a reddish appearance instead of what once may have been a white/yellow hot star.

Answer 9

Collapse isn't the correct term for this. Allow me to explain. As soon as a star "turns" on it is considered to be in its main sequence which is the longest phase of any stars life. Our sun is currently in the main sequence. During this phase our low mass sun is "burning" hydrogen by nuclear fusion to create helium and the by product is light or photons. As this process is inevitably over our sun has burned all the hydrogen, a helium shell is formed at the core of the star or sun. This unstable core causes the star to swell and form a red giant which is a new phase that may last a few million years. Then when all is burnt in the red giant star it calmly sheds its outside gas leaving behind only the hot core which can be seen as a planetary nebula. Eventually nothing is left but the cooling core which is the white dwarf. <the reason i said sun sometimes is because our sun is a low mass star and low mass stars go out like this. Our sun is 5 billion years old and has another 5 billion left. It is the very high mass stars that go supernova and go out with a bang

Answer 10

I am not that sure, but, apparently, the gravity on the outer layers is not that strong, so when the nuclear fusions occur there, they produce more energy than the gravity.