Why does mass determine the main-sequence lifetime of a star?
Because more massive stars burn fuel faster and therefore have shorter lives
. Because more massive stars have more fuel and therefore have longer lives.
Why do the most massive stars have the shortest lifetimes?
The most massive stars have the shortest lifetimes.
Because they have most fuel, they burn it so prodigously that their lifetimes are very short
. A stars time on the main sequence varies from a few million to 2×10
11
. As we will see later, the way in which a star evolves depends on its mass.
Why are main sequence lifetimes shorter for more massive stars?
1. More massive stars start with more mass but have shorter main-sequence lifetimes. … Their
high mass causes their cores to have HIGH DENSITY and HIGH TEMPERATURE
, making the rate of hydrogen fusion very rapid.
Why do smaller stars stay on the main sequence longer than massive stars?
A smaller star has less fuel, but its rate of fusion is not as fast. Therefore, smaller stars live longer than larger stars
because their rate of fuel consumption is not as rapid
.
What happens to a star physically when it starts to burn larger elements?
Helium burns to forge an even heavier mix of carbon, nitrogen and oxygen
, and this renewed burst of energy puffs the star out into a vastly larger red giant. If the star is small enough, these heavier elements will never reach the burning point themselves and the fusion process will stop.
Why is it easier for Red Giants to lose mass than main-sequence stars?
All through the star’s life after it first started nuclear reactions,
it has been losing mass as it converted some mass to energy and other mass was lost in the winds
. This means that even though a red giant is large in terms of linear size, it is less massive than the main sequence star it came from.
Which star lives the shortest lifespan?
Massive Stars
When a star is more than ten times as massive as the sun, it becomes a Supergiant star.
Supergiants
have the shortest lifespans of any star, as the temperatures in a supergiant’s core get so high that it is able to fuse the helium that is left over after hydrogen burning has stopped.
Which star type has the shortest lifespan?
The life span of stars ranges from about 10 million years for the blue giants to about 100 billion years for the
red dwarfs
. The most common type of star is the red dwarf (lower right); the least common type is the blue giant (upper left).
What stars last the longest?
Red dwarf stars make up the largest population of stars in the galaxy, but they hide in the shadows, too dim to be seen with the naked eye from Earth. Their limited radiance helps to extend their lifetimes, which are far greater than that of the sun.
Do heavier stars live longer?
A star’s life expectancy depends on its mass. Generally,
the more massive the star
, the faster it burns up its fuel supply, and the shorter its life. The most massive stars can burn out and explode in a supernova after only a few million years of fusion.
What happens in the first stage of a star much bigger than the sun’s death?
Stars More Massive Than the Sun
Once the core has turned to iron, it can burn no longer
. The star collapses by its own gravity and the iron core heats up. The core becomes so tightly packed that protons and electrons merge to form neutrons.
What is the largest star in the universe?
The largest known star in the universe is
UY Scuti
, a hypergiant with a radius around 1,700 times larger than the sun.
What happens when a star bigger than the sun’s core collapses?
If the core is larger, it will collapse
into a black hole
. To turn into a neutron star, a star must start with about 7 to 20 times the mass of the Sun before the supernova. Only stars with more than 20 times the mass of the Sun will become black holes.
What is the life cycle of a massive star?
Step 1 – Green – A cloud of gas and dust collapses due to gravity, creating a protostar. Step
4 – Red – The star expands into a red giant when the star’s hydrogen
level drops. … Step 5 – Orange – Different fusion processes occur.
Why does a dying star collapse and explode?
Really massive stars use up their hydrogen fuel quickly, but are hot enough to fuse heavier elements such as helium and carbon. Once there is no fuel left, the star collapses and
the outer layers explode as a ‘supernova
‘.
Why do stars turn into red giants?
When
hydrogen fuel at the centre of a star is exhausted
, nuclear reactions will start move outwards into its atmosphere and burn the hydrogen that’s in a shell surrounding the core. As a result, the outside of the star starts to expand and cool, turning much redder.
