A rose blooming in space
1er septembre 2002
Resembling a delicate rose floating
in space, the nebula N11A is seen in a new light in a
true-colour image taken by the NASA/ESA Hubble Space Telescope.
Fierce radiation from massive stars
embedded at the centre of N11A illuminates the
surrounding gas with a soft fluorescent glow.
N11A lies within a spectacular star-forming region in the
Large Magellanic Cloud, a small nearby companion galaxy
to our own Milky Way Galaxy, visible from the Southern
Hemisphere. This nebula is particularly interesting for
astronomers since it is the smallest and most compact
nebula in that region and represents the most recent
massive star formation event there. rose_large.jpg Figure N11A is located in the constellation of Dorado (the
Goldfish). This true-colour Hubble image is composed of
three narrow-band filter images obtained with Hubble’s
Wide Field Planetary Camera 2 on 17 May 2000. The three
images were obtained using a 1040 second exposure
through a red filter (ionised hydrogen, H-alpha), a 1200
second exposure through a green filter (ionised oxygen),
and a 1040 second exposure through a blue filter (ionised
hydrogen, H-beta). N11A is about 10 arc-seconds in size,
corresponding to about 8 light-years at the distance of
the Large Magellanic Cloud (168,000 light-years). Click on the image to view a higher resolution version
The excellent imaging power of Hubble has enabled
astronomers to see this nebula in more detail and to
study the structure of the hot gas envelope as well as the
stars embedded in its centre. Shocks and strong stellar
winds from the recently born, massive stars in the bright
core of N11A have scooped out a cavity in the gas and
dust. The fierce radiation causes the surrounding gas to
fluoresce in a way similar to a neon light.
Hubble’s image provides a much clearer picture of the
nebula, making it possible for the first time to identify the
stars that actually make it glow. Such information is
essential for a better understanding of the formation of
massive stars, that is, stars more than 10 times as heavy
as our Sun. "We need to study the properties of
star-forming regions in our neighbouring galaxies to
understand how stars are formed in the distant, young
Universe," explains Mohammad Heydari-Malayeri who led
the teamstudying these Hubble observations.
Mohammad Heydari-Malayeri (Observatoire de Paris, France), Vassilis Charmandaris (Cornell University, USA & Observatoire de Paris, France), Lise Deharveng (Observatoire de Marseille, France), Michael R. Rosa (ST-ECF, Germany), Daniel Schaerer (Observatoire Midi-Pyrénées, France), and Hans Zinnecker (Astrophysikalishes Institut Posdam, Germany). This communiqué echoes the 12 Sep. 2002 press-release from the European Space Agency (ESA). For more information : Special page on N11A
Reference : M. Heydari-Malayeri, V. Charmandaris, L. Deharveng, M.R. Rosa, D. Schaerer, H. Zinnecker "HST observations of the LMC compact HII region N11A", 2001, A&A, 372, 527 Contact
Mohammad Heydari-Malayeri (Observatoire de Paris, LERMA)
Dernière modification le 4 mars 2013