Located about 5,000 light-years from Earth, in the constellation of Centaurus, the Boomerang Nebula is a cloud of gas and dust left behind by a dying star. It is the remains of a red giant star that has collapsed under its own gravity and blown off its outer layers of gas and dust. The remaining core of the star has shrunk and heated to become a white dwarf, and the ejected material has expanded and cooled to form the Boomerang Nebula.

The temperature of the Boomerang Nebula is so cold that it is close to absolute zero, the theoretical lowest temperature that can be reached. Absolute zero is -273.15 Celsius, or 0 Kelvin. The Boomerang Nebula is only 1 degree Celsius above absolute zero, making it the coldest place in the universe that has been observed so far.

The Boomerang Nebula was discovered in 1980 by Australian astronomers using the Anglo-Australian Telescope. It was later observed in detail by the Hubble Space Telescope and other telescopes. The nebula is a popular object for study by astronomers because of its extreme temperature and its unique shape, which resembles a boomerang.