jeudi 15 décembre 2011

Young star rebels against its parent cloud












ESA - Hubble Space Telescope logo.

15 December 2011

Hubble’s Wide Field Camera 3 has captured this image of a giant cloud of hydrogen gas illuminated by a bright young star. The image shows how violent the end stages of the star-formation process can be, with the young object shaking up its stellar nursery.

Animation of S 106

Despite the celestial colours of this picture, there is nothing peaceful about star forming region Sh 2-106, or S106 for short. A devilish young star, named S106 IR, lies in it and ejects material at high speed, which disrupts the gas and dust around it. The star has a mass about 15 times that of the Sun and is in the final stages of its formation. It will soon quieten down by entering the main sequence, the adult stage of stellar life.

Hubble view of star-forming region S106

For now, S106 IR remains embedded in its parent cloud, but it is rebelling against it. The material spewing off the star not only gives the cloud its hourglass shape but also makes the hydrogen gas in it very hot and turbulent. The resulting intricate patterns are clearly visible in this Hubble image. 

The young star also heats up the surrounding gas, making it reach temperatures of 10 000 degrees Celsius. The star’s radiation ionises the hydrogen lobes, making them glow. The light from this glowing gas is coloured blue in this image.

Hubble / Subaru composite of star-forming region S 106

Separating these regions of glowing gas is a cooler, thick lane of dust, appearing red in the image. This dark material almost completely hides the ionising star from view, but the young object can still be seen peeking through the widest part of the dust lane.

S106 was the 106th object to be catalogued by the astronomer Steward Sharpless in the 1950s. It is a few thousand light-years distant in the direction of Cygnus (The Swan). The cloud itself is relatively small by the standards of star-forming regions, around 2 light-years along its longest axis. This is about half the distance between the Sun and Proxima Centauri, our nearest stellar neighbour.

Ground-based view of the area around star-forming region S 106

This composite picture was obtained with the Wide Field Camera 3 on the NASA / ESA Hubble Space Telescope. It results from the combination of two images taken in infrared light and one which is tuned to a specific wavelength of visible light emitted by excited hydrogen gas, known as H-alpha. This choice of wavelengths is ideal for targetting star-forming regions. The H-alpha filter isolates the light emitted from hydrogen in gas clouds while the infrared light can shine through the dust that often obscures these regions.

Zooming in on S 106

Videos:

Hubblecast 51: Star-forming region S 106: http://www.spacetelescope.org/videos/heic1118a/

Pan over S 106: http://www.spacetelescope.org/videos/heic1118d/

Artist’s impression of S 106: http://www.spacetelescope.org/videos/heic1118e/

Related Links:

Hubble overview: http://www.esa.int/science/hubble

Hubble factsheet: http://www.esa.int/esaSC/SEMB5E1A6BD_index_0.html

Hubblecast at the Hubble ESA Information Centre: http://www.spacetelescope.org/videos/archive/topic/hubblecast//

Hubble in depth: http://sci.esa.int/science-e/www/object/index.cfm?fobjectid=47209

Where is Hubble now?

Track Hubble: http://www.esa.int/esaSC/SEMK8E2PL7F_index_0.html

ESA Hubble website: http://www.spacetelescope.org/

Images, Text, Credits: NASA / ESA / the Hubble Heritage Team (STScI / AURA) / NAOJ / Digitized Sky Survey 2 (Acknowledgement: Davide De Martin) / Videos: NASA, ESA, and G. Bacon, T. Borders, L. Frattare, Z. Levay, and F. Summers (Viz 3D team, STScI) / Digitized Sky Survey 2, NAOJ and Nick Risinger. Music: John Dyson (from the album Moonwind).

Greetings, Orbiter.ch