ESO's Very Large Telescope has delivered the most detailed infrared
image of the Carina Nebula stellar nursery taken so far. Many previously
hidden features, scattered across a spectacular celestial landscape of
gas, dust and young stars, have emerged. This is one of the most
dramatic images ever created by the VLT.
Deep in the heart of the southern Milky Way lies a stellar nursery
called the Carina Nebula. It is about 7500 light-years from Earth in the
constellation of Carina (The Keel) [1]. This cloud of glowing gas and
dust is one of the closest incubators of very massive stars to Earth and
includes several of the brightest and heaviest stars known. One of
them, the mysterious and highly unstable star Eta Carinae, was the
second brightest star in the entire night sky for several years in the
1840s and is likely to explode as a supernova in the near future, by
astronomical standards. The Carina Nebula is a perfect laboratory for
astronomers studying the violent births and early lives of stars.
Although this nebula is spectacular in normal visible-light pictures
(eso0905), many of its secrets are hidden behind thick clouds of dust.
To penetrate this veil a European team of astronomers, led by Thomas
Preibisch (University Observatory, Munich, Germany) has used the power
of ESO's Very Large Telescope along with an infrared-sensitive camera
called HAWK-I [2].
Hundreds of individual images have been combined to create this
picture, which is the most detailed infrared mosaic of the nebula ever
taken and one of the most dramatic images ever created by the VLT. It
shows not just the brilliant massive stars, but hundreds of thousands of
much fainter stars [3] that were previously invisible.
The dazzling star Eta Carinae itself appears at the lower left of the
new picture. It is surrounded by clouds of gas that are glowing under
the onslaught of fierce ultraviolet radiation. Across the image there
are also many compact blobs of dark material that remain opaque even in
the infrared. These are the dusty cocoons in which new stars are
forming.
Over the last few million years this region of the sky has formed
large numbers of stars both individually and in clusters. The bright
star cluster close to the centre of the picture is called Trumpler 14.
Although this object is seen well in visible light, many more fainter
stars can be seen in this infrared view. And towards the left side of
the image a small concentration of stars that appear yellow can be seen.
This grouping was seen for the first time in this new data from the
VLT: these stars cannot be seen in visible light at all. This is just
one of many new objects revealed for the first time in this spectacular
panorama.
Notes
[1] Carina is the keel of the mythological ship Argo, of Jason and the Argonauts fame.
[2] Dusty regions of space absorb and scatter short wavelength blue
light more than the longer wavelength red. This effect also explains why
sunsets on Earth are often red, particularly when the atmosphere is
dusty. In some dusty parts of the sky, particularly in star formation
regions such as the Carina Nebula, this effect is so strong that no
visible light gets through at all. Astronomers overcome this problem by
observing in infrared light using special cameras such as HAWK-I on
ESO's VLT or the VISTA infrared survey telescope.
[3] One of the main goals of the astronomers was to search for stars
in this region that were much fainter and less massive than the Sun. The
image is also deep enough to allow the detection of young brown dwarfs.
This broad panorama of the Carina Nebula, a region of massive star
formation in the southern skies, was taken in infrared light using the
HAWK-I camera on ESO's Very Large Telescope. Many previously hidden
features, scattered across a spectacular celestial landscape of gas,
dust and young stars, have emerged. (Credit: ESO/T. Preibisch)
The above story is reprinted from materials provided by ESO.
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