Latest views of the V838 Monocerotis light echo from Hubble

Oct 26, 2006
Latest views of the V838 Monocerotis light echo from Hubble
These images show the evolution of the light echo around the star V838 in the constellation of Monoceros. They were taken by the Hubble Advanced Camera for Surveys in November 2005 (left) and again in September 2006 (right). The numerous whorls and eddies in the interstellar dust are particularly noticeable. Possibly they have been produced by the effects of magnetic fields in the space between the stars. Credit: NASA, ESA and H. Bond (STScI)

The unusual variable star V838 Monocerotis (V838 Mon) continues to puzzle astronomers. This previously unknown star underwent an outburst early in 2002, during which it temporarily increased in brightness to become 600,000 times more luminous than our Sun. Light from this sudden eruption is illuminating the interstellar dust surrounding the star, producing the most spectacular "light echo" in the history of astronomy.

As light from the eruption propagates outward into the dust, it is scattered by the dust and travels to the Earth. The scattered light has travelled an extra distance in comparison to light that reaches Earth directly from the stellar outburst. Such a light echo is the optical analogue of the sound echo produced when an Alpine yodel is reflected from the surrounding mountainsides.

The NASA/ESA Hubble Space Telescope has been observing the V838 Mon light echo since 2002. Each new observation of the light echo reveals a new and unique "thin-section" through the interstellar dust around the star. This release shows new images of the light echo from the Hubble Advanced Camera for Surveys taken in November 2005 (left) and again in September 2006 (right). The numerous whorls and eddies in the interstellar dust are particularly noticeable. Possibly they have been produced by the effects of magnetic fields in the space between the stars.

The Hubble observations have been used to determine the distance to V838 Mon, using a technique based on the polarisation of the reflected light. Hubble has polarising filters that only pass light that vibrates at certain angles. This method yields a distance of 20,000 light-years for V838 Mon, suggesting that, during its outburst, V838 Mon was one of the brightest stars in the entire Milky Way. Although the reason for the eruption is still unclear, some astronomers have suggested it might have resulted from the collision of two stars.

Source: Hubble Information Centre

Explore further: Dusty substructure in a galaxy far far away

Related Stories

Light echoes from V838 Mon

Mar 19, 2013

(Phys.org) —What caused this outburst of V838 Mon? For reasons unknown, star V838 Mon's outer surface suddenly greatly expanded with the result that it became the brightest star in the entire Milky Way ...

Black hole activity deduced from reflected X-rays

Oct 03, 2014

The supermassive black hole in the center of our galaxy, known as Sagittarius A*, is pretty quiet for a black hole. It does however flare up from time to time, when material is captured, as can be seen in ...

Echoes from Eta Carinae's great eruption

Dec 29, 2011

During the mid 1800's, the well known star η Carinae underwent an enormous eruption becoming for a time, the second brightest star in the sky. Although astronomers at the time did not yet have the technology ...

Disaster lessons: What you don't know can kill you

Oct 17, 2005

Something remarkable happened on the island closest to the epicenter of the great Sumatra-Andaman earthquake last December: Only seven of the island's 78,000 inhabitants died. This is despite the fact tsunamis hit the island ...

Recommended for you

Dusty substructure in a galaxy far far away

3 hours ago

Scientists at the Max Planck Institute for Astrophysics (MPA) have combined high-resolution images from the ALMA telescopes with a new scheme for undoing the distorting effects of a powerful gravitational ...

ALMA disentangles complex birth of giant stars

3 hours ago

A research group led by Aya Higuchi, a researcher at Ibaraki University, conducted observations of the massive-star forming region IRAS 16547-4247 with the Atacama Large Millimeter/submillimeter Array (ALMA). ...

Image: The tumultuous heart of the Large Magellanic Cloud

Mar 31, 2015

A scene of jagged fiery peaks, turbulent magma-like clouds and fiercely hot bursts of bright light. Although this may be reminiscent of a raging fire or the heart of a volcano, it actually shows a cold cosmic ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.