The hottest stars are blue, with their surface temperatures falling anywhere between 10,000 K and 50,000 K.
The energy of the blue star is therefore more than the energy of the Sun (since it is inversely proportional). Therefore, the temperature of the star will be greater than the temperature of the Sun, i.e., the star which appears blue will be much hotter than the Sun.
Most of them look white, but some are distinctly red in color while others are blue. A star's color tells us about its temperature and mass, and blue stars are the hottest and most massive of all.
Blue stars have estimated surface temperatures of 25,000 kelvin (K) (44,540 degrees F/ 24,726 degrees C), while red stars are much cooler at around 3,000 K (4,940 degrees F/ 2,726 degrees C), according to the University of Central Florida.
The surface temperature of a star determines the color of light it emits. Blue stars are hotter than yellow stars, which are hotter than red stars.
Although you can spot many colors of stars in the night sky, purple and green stars aren't seen because of the way humans perceive visible light. Stars are a multicolored bunch. There are red giants on the verge of explosions.
Red stars are the coolest. Yellow stars are hotter than red stars. White stars are hotter than red and yellow. Blue stars are the hottest stars of all.
The hottest: WR 102
These stars not only burn incredibly hot and bright, but their stellar winds also blast much of their potential fuel into space. The hottest known star, WR 102, is one such Wolf-Rayet, sporting a surface temperature more than 35 times hotter than the Sun.
The temperature in a supernova can reach 1,000,000,000 degrees Celsius. This high temperature can lead to the production of new elements which may appear in the new nebula that results after the supernova explosion.
O stars are the hottest, with temperatures from about 20,000K up to more than 100,000K. These stars have few absorption lines, generally due to helium. These stars burn out in a few million years.
In astronomy, a green star is a white or blueish star that appears greenish in some viewing conditions (see § Psychology below). Under typical viewing conditions, there are no greenish stars, because the color of a star is more or less given by a black-body spectrum.
After puffing off its outer layers, the star collapses to form a very dense white dwarf. One teaspoon of material from a white dwarf would weigh up to 100 tonnes. Over billions of years, the white dwarf cools and becomes invisible.
According to a new study, a star discovered 75 light-years away is no warmer than a freshly brewed cup of coffee. Dubbed CFBDSIR 1458 10b, the star is what's called a brown dwarf.
Eta Carinae could be as large as 180 times the radius of the Sun, and its surface temperature is 36,000-40,000 Kelvin. Just for comparison, 40,000 Kelvin is about 72,000 degrees F. So it's the blue hypergiants, like Eta Carinae, which are probably the hottest stars in the Universe.
Hot stars appear blue because most energy is emitted in the bluer parts of the spectrum. There is little emission in the blue parts of the spectrum for cool stars - they appear red.
Stellar black holes are very cold: they have a temperature of nearly absolute zero – which is zero Kelvin, or −273.15 degrees Celsius.
The hottest thing in the Universe (Supernova)
Supernovas are the hottest thing in the Universe as they reach a million degrees Celsius. These explosive events occur when a star between 8 and 40 times more massive than our Sun reaches the end of its stellar lifecycle and explodes when its core collapses.
A CERN experiment at the Large Hadron Collider created the highest recorded temperature ever when it reached 9.9 trillion degrees Fahrenheit. The experiment was meant to make a primordial goop called a quark–gluon plasma behave like a frictionless fluid. That's more than 366,000 times hotter than the center of the Sun.
Neutron stars produce no new heat. However, they are incredibly hot when they form and cool slowly. The neutron stars we can observe average about 1.8 million degrees Fahrenheit, compared to about 9,900 degrees Fahrenheit for the Sun. Neutron stars have an important role in the universe.
A supernova is the hottest thing in the universe. The temperatures at the core during an explosion skyrocket up to 6000X the temperature of the sun's core.
Violet: 39400 °C (71000 °F)
Violet stars are of two temperature ranges: those whose Planckian peak wavelength lies between 380 and 450 nm, or 6700-7900 K temperature and those above the violet range in the ultraviolet that appear violet to blue in color. For example, A spectral type stars range in temperature from 7600 to 11,500 K.
The biggest star in the universe (that we know of), UY Scuti is a variable hypergiant with a radius around 1,700 times larger than the radius of the sun. To put that in perspective, the volume of almost 5 billion suns could fit inside a sphere the size of UY Scuti.