What is true about the hottest stars?

Answer 1

Blue hypergiant stars are the hottest stars in the galaxy. These stars are more than 100 times the mass of the sun, and their blue color indicates how incredibly hot they are. One example is the star, Eta Carinae. Its surface temperature is 36000-40000 Kelvin. 40000 kelvin is 72000 degrees Fahrenheit.

Answer 2

The hottest Stars are the blue hyper giants, stars with masses greater than 100 times our own suns mass. The light they emit is at the blue end of the spectrum. R136a1 is a good candidate for the hottest known star, estimated to have a surface temperature of around 50,000 degrees Kelvin.

Answer 3

The blue ones (which are actually hotter than the white). See: http://www.astronomynotes.com/starprop/s12.htm for a list of colors and temperature.

----

The hottest star in the universe is the Neutron Star burning on creation at a temperature of over 1 billion degrees kelvin. However, the huge number of neutrinos it emits carries away so much energy that the temperature falls within a few years to around 1 million kelvins. It would appear white to the eye.

The next hottest are O type stars (aka Blue Giants) which have a temperature of greater than 30,000 kelvin and will have a colour of, as the name suggests, blue!

Answer 4

Protostar is the earliest stage.

This is when the light and heat given off is caused by the friction of the gases passing each other and not by nuclear fusion. This part of the stars life usually lasts about 150,000 years, then it condenses enough to being Nuclear Fusion and a real star is born.

See related question.

Answer 5

Type O.

The hottest star is purple.

From hottest to coldest:

1. Purple
2. Blue
3. Green (If there is a green star)
4. Yellow (If there is a yellow star)
5. Orange (If there is an orange star)
6. Pink (If there is a pink star)
7. Red

I think it goes in order from darkest (purple), to lightest (yellow), and then darker (red).

I'm not sure but my sister knows.

Answer 6

Each star in the sky is an enormous glowing ball of gas. Our sun is a medium-sized star.

A star is born when an enormous cloud of hydrogen gas collapses until it is hot enough to burn nuclear fuel (producing tremendous amounts heat and radiation). As the nuclear fuel runs out (in about 5 billion years), the star expands and the core contracts, becoming a giant star which eventually explodes and turns into a dim, cool object (a black dwarf, neutron star, or black hole, depending on its initial mass).

The largest stars have the shortest life span (still billions of years); more massive stars burn hotter and faster than their smaller counterparts (like the Sun).

But it's the Nuclear Fusion and Nucleosynthesis that makes them hot.

Stars are giant nuclear reactors.

In the center of stars, atoms are taken apart by tremendous atomic collisions that alter the atomic structure and release an enormous amount of energy.

This makes stars hot and bright.

In most stars, the primary reaction converts hydrogen atoms into helium atoms, releasing an enormous amount of energy.

This reaction is called nuclear fusion because it fused the nuclei (center) of atoms together, forming a new nucleus.

The process of forming a new nucleus (and element) is nucleosynthesis.

Answer 7

All stars start out as object collecting matter in a nebula, this stage is called a proto-star, specifically T Tauri type stars. As they gather mass, they become hotter and denser. However, if the proto-star is unable to gather enough matter, it will not be hot enough to begin fusing helium and will be a brown dwarf. If a proto-star gathers enough mass, it's core becomes hot enough to initiate hydrogen fusion. This is the main-sequence of stars; the most common path a star follows. A star spends the majority of it's life in the main-sequence phase, about 9 billion years for mid-size stars.

Once a main-sequence star runs out of hydrogen, it's core will partially collapse, initiating the red giant phase. The collapse heats up and pressurizes the core enough to allow it to fuse the helium in the core into carbon. Once it runs out of carbon, another collapse occurs, allowing it to fuse the carbon into neon, then the neon into oxygen, then oxygen into silicon and finally silicon into nickel, which decays into iron. This is often the end of the red-giant phase.

At this point, the core density is very important and is the deciding factor for the ultimate fate of the star. A lower/mid-density (Under 8 solar masses) star will result in all of it's matter (Envelope) being ejected outwards, forming a planetary nebula with a white dwarf in the center. At this point, it will take about 10 quadrillion years for the core to cool to near-absolute zero. This will be the fate of the Sun.

Exceptionally massive stars will only make it about halfway through the red giant phase before the next stage occurs.

If the star is massive enough (25 or more solar masses), the core will be extremely dense, to the point where quantum degeneracy cannot hold to core from collapsing. If the core itself is 1.4 to 3.2 solar masses, it will collapse down to a radius of a couple dozen kilometers. This is called a neutron star. It is an unfathomably dense star. A neutron star will continue its orbit until it cools. The collapse is halted by quantum degeneracy and when the collapse stops, all of the star's matter is shot back in a shockwave called a supernova or hypernova.

If the core was over 3.2 solar masses, the core will completely collapse into a gravitational singularity (It will still have a supernova explosion though), or more commonly known as black holes.

Answer 8

An O star is the hottest with a temperature of greater than 30,000 kelvin and will have a colour of blue

****

*****

******

The hottest star in the universe is the Neutron Starburning on creation at a temperature of over 1 billion degrees kelvin. However, the huge number of neutrinos it emits carries away so much energy that the temperature falls within a few years to around 1 million kelvins. It would appear white to the eye.

Answer 9

A supernova may have a core temperature of a billion kelvin - or several billion kelvin in the case of a hypernova (a subtype of the supernova).

Perhaps a supernova doesn't really count, because it's an exploding star, not a "regular" star.
Also, I think it's usually the "surface temperature" (not the core temperature)
that is considered when talking about the hottest star.
The answer, I think, is rather surprising to most people.
The star with the highest known surface temperature is actually a white dwarf.
White dwarf stars can't even be seen with optical aid, such as a telescope.

Answer 10

the star will go into a blue dwarf, then die.