How does the initial mass of a star compare to its final size?

Answer 1

Medium mass stars can be up to 8 times the mass of our sun. High mass stars are larger than 8 times the mass of our sun. The smaller medium mass stars, between about 1 and 4 times the size of our sun, will eventually become red giants, before becoming white dwarfs and eventually cooling through brown dwarfs to black dwarfs. Larger medium mass stars ranging between about 4 and 8 times the mass of our sun will become neutron stars. High mass stars will become supernovas and then black holes. By the way, low-mass stars have insufficient mass to generate enough heat to go through a giant phase.

Note: The sizes listed are approximate and may vary depending on the model used.

Answer 2

Small stars have a mass upto one and a half times that of the Sun. Stage 1- Stars are born in a region of high density Nebula, and condenses into a huge globule of gas and dust and contracts under its own gravity. This image shows the Orion Nebula or M42 . Stage 2 - A region of condensing matter will begin to heat up and start to glow forming Protostars. If a protostar contains enough matter the central temperature reaches 15 million degrees centigrade. This image is the outflow (coloured red)and protostar. Stage 3 - At this temperature, nuclear reactions in which hydrogen fuses to form helium can start. Stage 4 - The star begins to release energy, stopping it from contracting even more and causes it to shine. It is now a Main Sequence Star. The nearest main sequence star to Earth, the Sun Stage 5 - A star of one solar mass remains in main sequence for about 10 billion years, until all of the hydrogen has fused to form helium. Stage 6 - The helium core now starts to contract further and reactions begin to occur in a shell around the core. Stage 7 - The core is hot enough for the helium to fuse to form carbon. The outer layers begin to expand, cool and shine less brightly. The expanding star is now called a Red Giant. The star expands to a Red Giant, below Stage 8 - The helium core runs out, and the outer layers drift of away from the core as a gaseous shell, this gas that surrounds the core is called a Planetary Nebula. A Planetary Nebula (Below, NGC 6543). Stage 9 - The remaining core (thats 80% of the original star) is now in its final stages. The core becomes a White Dwarf the star eventually cools and dims. When it stops shining, the now dead star is called a Black Dwarf. Massive Stars - The Life of a Star of about 10 Solar Masses Massive stars have a mass 3x times that of the Sun. Some are 50x that of the Sun Stage 1 - Massive stars evolve in a simlar way to a small stars until it reaces its main sequence stage (see small stars, stages 1-4). The stars shine steadily until the hydrogen has fused to form helium ( it takes billions of years in a small star, but only millions in a massive star). Stage 2 - The massive star then becomes a Red Supergiant and starts of with a helium core surrounded by a shell of cooling, expanding gas. The massive star is much bigger in its expanding stage. (A Red Supergiant,below). Stage 3 - In the next million years a series of nuclear reactions occur forming different elements in shells around the iron core. Stage 4 - The core collapses in less than a second, causing an explosion called a Supernova, in which a shock wave blows of the outer layers of the star. (The actual supernova shines brighter than the entire galaxy for a short time). The set of images below shows the star going into a stage called Supernova and contracting to become a neutron star The images above were from the HEASARC Homepage Stage 5 - Sometimes the core survives the explosion. If the surviving core is between 1.5 - 3 solar masses it contracts to become a a tiny, very dense Neutron Star. If the core is much greater than 3 solar masses, the core contracts to become a Black Hole.

Answer 3

In inverse proportion. Stars like the Sun will end up as Red Dwarfs, somewhat bigger than Jupiter; more massive ones will pass through a nova stage and end as White Dwarfs, about the size of the Earth; much more massive ones will become Neutron Stars only a few kilometers in diameter and the most massive ones of all will pull out of physical space altogether, so in effect they will have no size whatever.

Answer 4

A mid-sized star becomes a red giant and then depending upon the composition of the core, helium or carbon, expands and the outer layers cool. In a massive star the core is so massive when it expands and cool it becomes a red supergiant that is unstable and becomes a type II supernova.

Answer 5

Not all neutron stars have been named, least not the largest.

However, we know that the largest a neutron star can be is about, one and half times the mass of our Sun.

This means the largest Neutron Star is about only 40Km, or about 30 miles.

The mass of a neutron star is between 1.35 and about 2.1 solar masses. Anything smaller than that would be a white dwarf instead; anything larger than that would become a black hole.

Answer 6

It would depend on the mass of the original star, and the nature of the nova explosion. It can't be much more than about three times the mass of the Sun; if it were more massive, it would create a black hole rather than a neutron star.

Answer 7

A neutron star would be practically invisible in normal light, but would generate a fairly substantial X-ray flux. They are pretty small, as well; 10 to 15 miles in diameter, so even if they were fairly bright, they wouldn't be visible from a really long way off.

Answer 8

It depends on the star. If it is a super-massive star, then it will explode into a fiery super-nova leaving behind a super dense black hole. If it is a star like our own sun, its mass would soon make it expand to a red giant star, consuming 3 inner planets (Mercury, Venus, and Earth), (4 some odd billion years from now) and then fade away until it turns into a white dwarf, which would be about the size of our Earth and slowly fade into nothing.

Answer 9

Only very VERY massive and bright stars can collapse into a black hole first off (type O stars usually), or it may collapse into a neutron star. But quite simply the mass before collapse is very similar or equal to the mass of the possible black hole later. BUT over time this black hole may collect matter and become more massive all depending on its area in space and the density and closeness of matter around the black hole. <hope that helped

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At the time of the collapse and during its occurrence, there's no reason for the

mass to change. It simply collapses into a much smaller volume ... approximately

zero volume, in fact. But since the mass and its location don't change, a planet in

orbit around the object wouldn't necessarily experience any gravity-related change.

Answer 10

The diameter is about 20 or 30 km.

About the size of a city.