Star Monocerotis V838

Star V838 Monocerotis

Monocerotis (V838 Mon) is a supergiant star, one of the most brilliant of our Galaxy, it is located in the constellation Monoceros about 20,000 light years.
The star at end of life will soon be exhausted its reserve of energy, but on 6 January 2002, this nova showed it was still alive, an intense shine gradually illuminated the cocoon of dust that has built up around its core.
This flash was detected in infrared with the Gemini telescope in Hawaii.
Scientists have quickly pointed at it, Hubble Space Telescope to analyze the variation of brightness that astronomers call an echo of light.
In this explosion, the light echo of the supergiant shows on the picture against the detailed structures of the dust cloud surrounding, drawing a volcano with a gaping mouth.
The violent explosion of the star caused a flash light energy which suddenly illuminated the dust while Hubble was watching him.
This light looks like explosion of a nova when at end of life, for lack of fuel, nuclear reactions can no longer contain the force of gravity, then the star ejects its gaseous envelope to release the stress of gravity .

But the most surprising is that V838 Monocerotis did not expel its outer layers. Instead, it has grown enormously in size. Its surface temperature is dropped to ridiculously low temperatures. This behavior is very unusual and completely different from an ordinary nova explosion. However, the explosion may represent a transitional phase ever observed in the evolution of a star. V838 Monocerotis has some similarities with the stars very unstable during aging called 'eruptive variables', some of which increase brightness suddenly and unexpectedly. The accuracy of the image taken by Hubble shows complexity of the internal cloud, which evokes a chaotic structure with an envelope in highly loaded to matter, while the interior is almost empty. It is possible that star Monocerotis V838 is a dying aster going through several cycles of contractions and explosions. The star is located in Monoceros constellation, near north celestial pole.

Note: Monoceros is a relatively light modern constellation, near the celestial equator, it is visible everywhere on Earth except at the poles. It occupies a large part of the Winter Triangle.

Image: V838 Monocerotis is an amazing star, then it seems to run out of fuel and ejected into space envelope of dust and gas, its size increases. Telescope image NASA/ESA Hubble Space.