Dec 2004
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=2004eso..presp..34.&link_type=abstract
ESO Press Release, 12/2004
Other
Scientific paper
The Tarantula Nebula is one of the most impressive views in the Southern sky, cf. ESO Press Photos 14a-g/02. Visible to the unaided eye in the Large Magellanic Cloud (LMC), a satellite galaxy of the Milky Way that is located in the direction of the southern constellation Doradus at a distance of about 170,000 light-years, this huge nebula is the prototype of what astronomers refer to as a "Giant HII region". In this complex of glowing gas and very hot and luminous stars, the gas is mainly composed of protons and electrons, which are kept apart by energetic photons emitted by the stars in this area.
The Tarantula Nebula (also designated 30 Doradus) owes its name to the arrangement of its brightest patches of nebulosity that somewhat resemble the legs of a spider. They extend from a central "body" where a cluster of hot stars (designated "R136") resides that illuminate the nebula. This name, of the biggest spiders on the Earth, is also very fitting in view of the gigantic proportions of the celestial nebula - it measures nearly 1,000 light years across!
While the central regions of 30 Doradus may be compared to a tarantula, the entangled filaments in the outskirts of this nebula - some of which are seen in PR Photo 34a/04 - could well be likened with its cobweb. They testify to an ongoing history of very vigorous activity and make this spectacular sky region a showcase of dramatic effects caused by the tremendous output of energy from the most massive stars known. Intricate colours
ESO PR Photo 34b/04
ESO PR Photo 34b/04
Filaments in the Tarantula Nebula in the LMC (ESO/MPG 2.2-m + WFI)
[Preview - JPEG: 400 x 420 pix - 216k] [Normal - JPEG: 800 x 839 pix - 656k] [FullRes - JPEG: 1628 x 1708 pix - 2.7M]
Caption: ESO PR Photo 34b/04 shows filaments of ionized gas in the proximity of the R136 cluster, which lies beyond the lower left edge of the photo. The different hues are due to different physical conditions that manifest themselves in the spectrum of the light emitted by the gas. Note also the dark lanes running roughly from bottom left to upper right, which are due to filaments of obscuring dust seen in projection against the background of bright nebulosity. The sky field measures 6.5 x 5.7 arcmin. North is up and East is left.
The marvellous richness of the filament colours is due to the varying conditions in the interstellar gas in this region, cf. PR Photo 34b/04. The red in these images is caused by emission of excited hydrogen atoms, the green shades correspond to emission from oxygen atoms from which two electrons ("doubly-ionized oxygen") have been "knocked off" by the energetic radiation of hot stars in the R136 cluster, that is located beyond the lower right corner of this photo. The intensity of this emission increases towards R136, explaining the yellowish colour near the edge of the photo.
A blue colour is contributed by singly-ionized atoms of oxygen. Other atoms like nitrogen and sulfur at different levels of ionization also add to the emission of the nebula at specific wavelengths. The observed colours thus probe the physical condition of the emitting gas and the temperature of the star(s) that excite(s) it. The intricate appearance of the filaments is mostly a consequence of turbulence in the interstellar gas, of the magnetic fields, and of the energy input by the massive stars in the neighbourhood. Supernovae blow interstellar "bubbles"
ESO PR Photo 34c/04
ESO PR Photo 34c/04
SNR 0543-689 in the LMC (ESO/MPG 2.2-m + WFI)
[Preview - JPEG: 400 x 459 pix - 232k] [FullRes - JPEG: 906 x 1039 pix - 1.1M]
ESO PR Photo 34d/04
ESO PR Photo 34d/04
SNR B0544-6910 in the LMC (ESO/MPG 2.2-m + WFI)
[Preview - JPEG: 400 x 455 pix - 272k] [FullRes - JPEG: 941 x 1071 pix - 1.3M]
Caption: ESO PR Photo 34c/04 shows a bright, compact nebula that is located on the North-Western rim of the ringshaped nebula DEM L 299. It is known as SNR 0543-689 and it is the remnant of a more recent supernova explosion. The sky field measures 3.6 x 3.5 arcmin. North is up and East is left. Another, even younger supernova remnant, B0544-6910 is shown in PR 34d/04. This sky field is located near the lower left corner of PR Photo 34a/04 and measures 3.7 x 3.6 arcmin; the orientation is the same.
The large ring-shaped nebula slightly to the lower-left (South-East) of the centre of PR 34a/04 is known as DEM L 299 [1]. Detailed investigations show that it represents an "interstellar bubble" which was "blown" by supernovae explosions, most probably happening millions of years ago, as massive stars near the centre of this structure ended their comparatively short lives in glorious flashes.
A closer inspection shows that another supernova exploded somewhat later near the rim, forming a bright and more compact nebula known as SNR 0543-689 (PR 34c/04). Other supernovae in this general field exploded even more recently, such as the one that created the remnant B0544-6910 (PR 34d/04) only a few tens of thousands of years ago, a blink of an eye by all astronomical standards. Nebulae with built-in powerhouses
ESO PR Photo 34e/04
ESO PR Photo 34e/04
The N 164 Nebula in the LMC (ESO/MPG 2.2-m + WFI)
[Preview - JPEG: 400 x 447 pix - 248k] [Normal - JPEG: 800 x 894 pix - 736k] [FullRes - JPEG: 1744 x 1949 pix - 3.3M]
ESO PR Photo 34f/04
ESO PR Photo 34f/04
The DEM L 297 Nebula in the LMC (ESO/MPG 2.2-m + WFI)
[Preview - JPEG: 400 x 459 pix - 240k] [FullRes - JPEG: 906 x 1039 pix - 1.2M]
Caption: ESO PR Photo 34e/04 shows N 164, a bright nebula, the glow of which is caused by hot stars inside it. The heating of the gas by these stars increases the pressure and causes such nebulae to expand, pushing outwards against their surroundings. A careful look at this nebula reveals locations where the expansion is encountering resistance by denser clouds of gas, producing bright, thin rims. The sky field measures 3.6 x 3.5 arcmin. North is up and East is left. PR Photo 34f/04 shows DEM L 297, another diffuse nebula that also glows due to stars embedded in it and whose "divided" appearance is due to the presence of obscuring dust lanes. The sky field measures 6.5 x 5.7 arcsec; the orientation is the same.
Not all the nebulae seen in this region are caused by supernovae, however. The glow of N 164 [1], a bright, extended red-yellow nebula just below DEM L 299, is mostly due to its own "private" powerhouse, that consists of several massive stars deeply embedded in its interior (PR Photo 34e/04).
The same holds for DEM L 297, the somewhat smaller and fainter nebula to the right of DEM L 299 (PR Photo 34f/04). It is divided into two half-circle formed segments by a dark lane of interstellar dust in front of it. Indeed, within the Tarantula complex many such dark and dusty clouds are seen in silhouette as they obscure bright nebulosity behind them. Many stellar clusters
ESO PR Photo 34g/04
ESO PR Photo 34g/04
NGC 2093 Stellar Cluster in the LMC (ESO/MPG 2.2-m + WFI)
[Preview - JPEG: 400 x 432 pix - 256k] [Normal - JPEG: 800 x 864 pix - 760k] [FullRes - JPEG: 1422 x 1535 pix - 2.2M]
ESO PR Photo 34h/04
ESO PR Photo 34h/04
NGC 2108 Stellar Cluster in the LMC (ESO/MPG 2.2-m + WFI)
[Preview - JPEG: 400 x 450 pix - 248k] [FullRes - JPEG: 702 x 789 pix - 680k]
Caption: ESO PR Photo 34g/04 shows the stellar cluster NGC 2093, a comparatively rich aggregate of young stars, a few tens of millions of years old. The hot temperature of the most massive of such young stars is responsible for its predominantly blue colour. The sky field measures 5.6 x 5.1 arcmin. North is up and East is left. ESO PR Photo 34h/04 shows the stellar cluster NGC 2108, a rich "mid-aged" cluster, about 600 million years old. A careful comparison with its neighbour NGC 2093 (PR Photo 34g/04) shows that the brightest stars of NGC 2108 are fainter and whiter than the brightest members of NGC 2093; this indicates that NGC 2108 is older. Note also the distinctly red star to the East (left) of the center of this cluster. This is a member of a stellar class referred to as "Carbon stars", cool giant stars that are characterized by the pre
No affiliations
No associations
LandOfFree
Caught in the Cobweb does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Caught in the Cobweb, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Caught in the Cobweb will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1025534