The Boomerang Nebula, located 5,000 light-years from Earth, is considered the coldest place in the universe. Astronomers call this nebula, which can only be observed from the southern hemisphere, the “refrigerator of the universe.” Its temperature is minus 272°C, just one degree above the temperature of absolute zero – minus 273.15°.
The Boomerang Nebula was discovered in 1979 by Swedish and American astronomers using a large telescope installed in Chile. It received the name “Boomerang” in 1980 – in telescopes located on Earth, the nebula looked like a curved cloud of an elongated shape.
The photographs of the nebula were taken by the Hubble Telescope sent into space for NASA and ESA, who jointly operate it. Last year, the crew of the American spacecraft Columbia installed a new and improved camera on the telescope, which increased the ability to capture images tenfold. In particular, the upgraded Hubble recorded the collision of galaxies located at a distance of 420 million light years. It will allow them to observe distant galaxies located in the so-called “twilight zone”, that is, in the initial period of their formation.
It has been established that the gas of the nebula absorbs microwave background radiation – the cosmic microwave background radiation left over from the Big Bang that gave birth to the Universe. Such a process can proceed only under conditions when the gas is cooled to a temperature below minus 270°C, which has not yet been observed anywhere in nature.
The Boomerang Nebula is a cloud of gas and dust ejected by a dying star at over 150 km/s, causing it to cool dramatically. Most likely, this cloud is cooled as a result of the same process as in home compression refrigerators – as a result of the rapid expansion of gas, although it is not excluded that another yet unnoticed object such as a “black hole” can also partially cool the nebula.
A spokesman for the European Space Agency said:
“Even at minus 270°C, the temperature established after the Big Bang is higher than that of this nebula. It is the only object found in nature so far that has a temperature lower than that of the background radiation left over from the Big Bang.”
The Boomerang Nebula is a unique object that allows scientists to better understand the processes taking place in the Universe. Its study can help reveal many of the mysteries of the cosmos and open up new possibilities for our understanding of the universe.