The coldest place in the universe

photo: This Hubble image was recorded using polarizing filters (analogous to polaroid sunglasses) and color coded by the angle associated with the polarized light.

The Boomerang Nebula (also called the Bow Tie Nebula) is a protoplanetary nebula located 5,000 light-years away from Earth in the Centaurus constellation. The nebula is measured at 1 K (−272.15 °C/−457.87 °F), the coldest place known in the universe. The Boomerang Nebula was formed from the outflow of gas from a star at its core. The gas is moving outwards at a speed of about 164 km/s and expanding rapidly as it moves out into space. This expansion is the cause of the nebula's very low temperature.The Boomerang Nebula was photographed in detail by the Hubble Space Telescope in 1998. It is believed that the nebula is a star or stellar system evolving toward the planetary nebula phase.Keith Taylor and Mike Scarrott called it the 'Boomerang Nebula' in 1980 after observing it with the Anglo-Australian telescope at the Siding Spring Observatory. Unable to view it with the same detail as with the Hubble, the astronomers saw merely a slight asymmetry in the nebula's lobes, suggesting a curved shape like a boomerang. The high-resolution Hubble images indicate that the 'Bow Tie Nebula' would perhaps have been a better name.The Boomerang Nebula is one of the Universe's peculiar places. In 1995, using the 15-metre Swedish ESO Submillimetre Telescope in Chile, astronomers revealed that it is the coldest place in the Universe found so far. With a temperature of −272 °C, it is only 1 kelvin warmer than absolute zero (the lowest limit for all temperatures). Even the −270 °C background glow from the Big Bang is warmer than this nebula. It is the only object found so far that has a temperature lower than the background radiation.The Hubble Space Telescope has "caught" the Boomerang Nebula in these new images taken with the Advanced Camera for Surveys. This reflecting cloud of dust and gas has two nearly symmetric lobes (or cones) of matter that are being ejected from a central star. Over the last 1,500 years, nearly one and a half times the mass of our Sun has been lost by the central star of the Boomerang Nebula in an ejection process known as a bipolar outflow. The nebula's name is derived from its symmetric structure as seen from ground-based telescopes. Hubble's sharp view is able to resolve patterns and ripples in the nebula very close to the central star that are not visible from the ground.This Nebula is the coldest place yet found anywhere in the universe.