The coldest place in the Universe

Human beings have always liked to analyze extremes. In this case we are going to talk about what is the coldest place in the universe. We are not talking about the coldest city on planet Earth, nor about our solar system. We refer to the coldest place in the entire universe known so far.

In this article we are going to tell you which is the coldest place in the universe, its characteristics and much more.

The coldest place in the Universe

5000 light years from the solar system is the coldest place in the universe. It is the Boomerang Nebula with a temperature of -272ºC. Just slightly above absolute zero, and even colder than the microwave background radiation. The coldest places in the universe are clouds of dust and gas.

The Boomerang Nebula is officially the coldest place in the universe. This nebula is relatively close, 5.000 light years from the Solar System. It is a planetary nebula, the product of a red giant star nearing the end of its life. Before it reached this stage, it was a Sun-like star that had been shedding its outer layers into space for the past few years.

Amazingly, it loses mass about a hundred times faster than other stars at a similar stage of evolution. Compared to the sun loses mass about 100 billion times faster than our star. This rate is so high that the star at the center of the Boomerang Nebula lost a mass equivalent to 1,5 times the mass of the Sun in just 1.500 years.

The gas is also ejected at an extremely high velocity of 164 km/s, releasing a large amount of energy. The result is a region of extreme cold, very close to absolute zero. This nebula is three times colder than the lowest temperature ever recorded on Earth

Boomerang Nebula temperature

The Boomerang Nebula has an internal temperature of -272ºC. Absolute zero is -273,15ºC. Objectively speaking, it is three times colder than the lowest temperature ever recorded on Earth.

Keep in mind that the coldest temperature recorded on Earth occurred in Vostok, Antarctica in 1983, when it reached -89,2°C. This is the coldest place in the world. But it's an uninhabited place, so usually when you talk about the coldest place on earth, it's usually somewhere else. Where it is inhabited, the coldest place on Earth is Siberta-Oymyakon (Eastern Siberia), with the coldest temperature recorded at -67,8ºC.

It is not related to the lowest temperature recorded (-32ºC) in Lake Estangento, Lleida Pyrenees, nor with the temperature reached in the officially coldest place in Spain: Molina de Aragón (Guadalajara).

And the boomerang nebula is too cold, its temperature is even lower than the temperature of the microwave background radiation. This radiation is the brightness of the first rays of light from the universe, cast about 377.000 years after the Big Bang.

nebula features

That is, the Boomerang Nebula absorbs minimal heat from the background microwave radiation. What was observed when it was discovered in 1980, when Keith Taylor and Mike Carrot studied it. Barely a decade later, in 1990, astronomer Raghvendra Sahai published a study that predicted the existence of extremely cold regions of the universe.

The proposed mechanism is the following: as the stellar wind moves away from the star, the stellar wind expands rapidly, causing the temperature to drop.

In other words, on a cosmic scale, it's like a kind of fridge. With this in mind, Sahai observed the Boomerang Nebula himself in 1995 to see if his guess was correct. It was there that the temperature of the nebula was determined and established as the coldest place in the universe.

In 2013, with the help of the ALMA radio telescope, the measurements were confirmed. In 2017, Sahai himself published a new study looking at what happens in the nebula. The temperature is so low due to the rapid acceleration of the gas ejected from the star. What is less clear is what caused it to explode at such a high speed. It was there that it was first suggested that it might be due to a red giant star. With one important caveat, that star is not alone. In fact, it will be part of a binary system with another less massive star, which will be an important component that will cause gas to be expelled at a very high rate.

Other phenomena such as the coldest place in the Universe

Sahai himself explained that the only way to eject so much mass at such a speed is through the gravitational interaction between two stars that are very close together. Considering its existence, a scene matching that seen in the Boomerang Nebula can be found.

To this we must add another detail. The outer layer is being ejected from two small points. The air expands and cools faster as it leaves the small opening. So, since then, efforts have been made to better understand the phenomenon. To do this, it is necessary to focus on the rest of the galaxy. What happens in the Boomerang Nebula is probably happening in other parts of the Milky Way.

With more examples, it is possible to study similarities and differences. Not only that, but the possibility of finding regions colder than the Boomerang Nebula and therefore closer to absolute zero is not ruled out.

As for Nebula, her future is very detailed. Like other planetary nebulae, it will eventually recede for thousands of years. By itself, the star will end its life as a white dwarf. Like a stellar corpse, incapable of any kind of fusion within it, it will slowly cool over huge time scales, a process that will outlive the current age of the Universe.

As you can see, science is advancing more and more and is capable of discovering these remote places. I hope that with this information you can learn more about the coldest place in the universe and its characteristics.