The absolute temperature (Kelvin) scale can be understood loosely as a measure of average kinetic energy. Usually, system temperatures are positive. However, in particular isolated systems, the temperature defined in terms of Boltzmann’s entropy can become negative.

On the absolute temperature scale, which is used by physicists and is also called the Kelvin scale, it is not possible to go below zero – at least not in the sense of getting colder than zero kelvin. Physicists have now created an atomic gas in the laboratory that nonetheless has negative Kelvin values.

On Kelvin scale the temperature is set at -273.15 when it is absolute zero, beyond which the temperatures cannot go. Thus, the scale unlike others starts at zero which is the lowest temperature on the scale. As lowest value on the Kelvin scale is zero, hence all figures are in positive value.

Hey Mate..! Kelvin does not have a negative value. There are no negative numbers on the Kelvin scale, as the lowest number is 0 K.

Nothing in the universe — or in a lab — has ever reached absolute zero as far as we know. Even space has a background temperature of 2.7 kelvins. But we do now have a precise number for it: -459.67 Fahrenheit, or -273.15 degrees Celsius, both of which equal 0 kelvin.

Lightning is way hotter. Lightning is up to 70000 degrees fahrenheit but lava is just 2240 degrees fahrenheit.

Since around 1997–2003, the problem is believed to have been solved by most cosmologists: modern cosmological measurements lead to a precise estimate of the age of the universe (i.e. time since the Big Bang) of 13.8 billion years, and recent age estimates for the oldest objects are either younger than this, or …

Many independent lines of scientific evidence show that the Earth and Universe are billions of years old. Current measurements yield an age of about 4.54 billion years for the Earth and about 13.8 billion years for the Universe.

HD 140283 (or the Methuselah star) is a metal-poor subgiant star about 200 light years away from the Earth in the constellation Libra, near the boundary with Ophiuchus in the Milky Way Galaxy. Its apparent magnitude is 7

Methuselah Star

But it also has a nickname — the Methuselah Star. That’s because measurements of its age say it’s at least 13 and a half billion years old, and perhaps a good bit older. Since the universe itself is only about 13. 8 billion years old, that makes the star one of the oldest around.

Throughout most of a star’s life, it is burning hydrogen at its core, which creates lots of energy and thus makes it appear blue. As stars age, they run out of hydrogen to burn, decreasing the amount of energy they emit.

about 10 billion years

red dwarfs

When the helium fuel runs out, the core will expand and cool. The upper layers will expand and eject material that will collect around the dying star to form a planetary nebula. Finally, the core will cool into a white dwarf and then eventually into a black dwarf. This entire process will take a few billion years.

According to study from a team of researchers from Calvin College in Grand Rapids, Michigan, a binary star system that will likely merge and explode in 2022. This is an historic find, since it will allow astronomers to witness a stellar merger and explosion for the first time in history.

Stars are born when large gas clouds collapse under gravity. When it eventually dies, it will expand to a form known as a ‘red giant’ and then all the outer layers of the Sun will gradually blow out into space leaving only a small White Dwarf star behind about the size of the Earth.

Stars are born within the clouds of dust and scattered throughout most galaxies. A familiar example of such as a dust cloud is the Orion Nebula. Known as a protostar, it is this hot core at the heart of the collapsing cloud that will one day become a star.

As light from a star races through our atmosphere, it bounces and bumps through the different layers, bending the light before you see it. Since the hot and cold layers of air keep moving, the bending of the light changes too, which causes the star’s appearance to wobble or twinkle.

In order to live on, the protostar will need to achieve and maintain equilibrium, a balance between gravity pulling atoms towards the center of the protostar and gas pressure pushing heat and light away from the center. When a star can no longer maintain this balance, it dies.

10 million K

If the star is large enough, it can go through a series of less-efficient nuclear reactions to produce internal heat. However, eventually these reactions will no longer generate sufficient heat to support the star agains its own gravity and the star will collapse.