ESA Science & Technology - V838 Monocerotis revisited: Space phenomenon imitates art [heic0405]

ACS image of V838 Monocerotis

Called a light echo, the expanding illumination of a dusty cloud around the star has been revealing remarkable structures ever since the star suddenly brightened for several weeks in early 2002. Though Hubble has followed the light echo in several snapshots, this new image shows swirls or eddies in the dusty cloud for the first time. These eddies are probably caused by turbulence in the dust and gas around the star as they slowly expand away. The dust and gas were likely ejected from the star in a previous explosion, similar to the 2002 event, which occurred some tens of thousands of years ago. The surrounding dust remained invisible and unsuspected until suddenly illuminated by the brilliant explosion of the central star two years ago.

The Hubble Space Telescope has imaged V838 Mon and its light echo several times since the star's outburst in January 2002, in order to follow the constantly changing appearance of the dust as the pulse of illumination continues to expand away from the star at the speed of light. During the outburst event, the normally faint star suddenly brightened, becoming 600 000 times more luminous than our Sun. It was thus one of the most luminous stars in the entire Milky Way, until it faded away again in April 2002. The star has some similarities to a class of objects called "novae", which suddenly increase in brightness due to thermonuclear explosions at their surfaces; however, the detailed behaviour of V838 Mon, in particular its extremely red colour, has been completely different from any previously known nova.

Nature's own piece of performance art, this structure will continue to change its appearance in coming years as the light from the stellar outburst continues to propagate outward and bounce off more distant black clouds of dust. Astronomers expect the echoes to remain visible for at least the rest of the current decade.

The colour image is composed of 3 different exposures through a blue filter (5250 seconds), a green filter (1050 seconds) and a near-infrared filter (300 seconds).

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Notes for editors

Animations of the discovery and general Hubble Space Telescope background footage are available from: http://www.spacetelescope.org/bin/videos.pl?searchtype=news&string=heic0405

Image credit: NASA, the Hubble Heritage Team (AURA/STScI) and ESA

The Hubble Space Telescope is a project of international cooperation between ESA and NASA.

Contacts

Lars Lindberg Christensen
Hubble European Space Agency Information Centre, Garching, Germany
Tel: +49-(0)89-3200-6306
Cellular (24 hr): +49-(0)173-3872-621
E-mail: larseso.org

Howard Bond
Space Telescope Science Institute, Baltimore, USA
Tel: +1-410-338-4718
E-mail: bondstsci.edu

Keith Noll
Space Telescope Science Institute, Baltimore, USA
Tel: +1-410-338-1828
E-mail: nollstsci.edu