Messier 78 (a reflection nebula in Orion)
This new image of the reflection nebula Messier
78 was captured using the Wide Field Imager camera on the MPG/ESO 2.2-metre
telescope at the La Silla Observatory, Chile. This colour picture was created
from many monochrome exposures taken through blue, yellow/green and red
filters, supplemented by exposures through a filter that isolates light from
glowing hydrogen gas. The total exposure times were 9, 9, 17.5 and 15.5 minutes
per filter, respectively.
ESO’s VLT reveals the Carina Nebula's hidden secrets
This broad image 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.
The Eagle Nebula
Three-colour composite
mosaic image of the Eagle Nebula (Messier 16, or NGC 6611), based on images
obtained with the Wide-Field Imager camera on the MPG/ESO 2.2-metre telescope
at the La Silla Observatory. At the centre, the so-called “Pillars of Creation”
can be seen. This wide-field image shows not only the central pillars, but also
several others in the same star-forming region, as well as a huge number of
stars in front of, in, or behind the Eagle Nebula. The cluster of bright stars
to the upper right is NGC 6611, home to the massive and hot stars that
illuminate the pillars. The “Spire” — another large pillar — is in the middle
left of the image.
This image is a
composite of 3 filters in the visible range: B (blue), V (green) and R (red).
The Eagle's EGGs
Messier 16 (M16), also
known as the Eagle Nebula, is located in the southern constellation of Serpens
(the Snake).
Using the infrared
multi-mode ISAAC instrument on the 8.2-m VLT ANTU telescope, European
astronomers were able to image the Eagle Nebula at near-infrared wavelength.
The ISAAC near-infrared images cover a 9 x 9 arcminutes region, in three
broad-band colours and with sufficient sensitivity to detect young stars of all
masses and — most importantly — with an image sharpness as good as 0.35
arcseconds.
The wide-field view of
M16 shows that there is much happening in the region. The first impression one
gets is of an enormous number of stars. Those which are blue in the infrared
image are either members of the young NGC 6611 cluster — whose massive stars
are concentrated in the upper right (north west) part of the field — or
foreground stars which happen to lie along the line of sight towards M16.
Most of the stars are
fainter and more yellow. They are ordinary stars behind M16, along the line of
sight through the galactic bulge, and are seen through the molecular clouds out
of which NGC 6611 formed. Some very red stars are also seen: these are either
very young and embedded in gas and dust clouds, or just brighter stars in the
background shining through them.
This photo is the
result of a three-colour composite mosaic image of the Eagle Nebula (Messier
16), based on 144 individual images obtained with the infrared multi-mode
instrument ISAAC on the ESO Very Large Telescope (VLT) at the Paranal
Observatory. At the centre, the so-called "Pillars of Creation" can
be seen. This wide-field infrared image shows not only the central three pillars
but also several others in the same star-forming region, as well as a huge
number of stars in front of, in, or behind the Eagle Nebula. The cluster of
bright blue stars to the upper right is NGC 6611, home to the massive and hot
stars that illuminate the pillars.
Technical information:
This image was made using the near-infrared camera ISAAC on the ESO 8.2-m VLT
ANTU telescope on April 8 and May 8 - 10, 2001. The full field measures
approximately 9.1 x 9.1 arcmin, covering roughly 17 x 17 light-years (5.3 x 5.3
pc) at the distance to the region (about 6,500 light-years or 2 kpc). This
required a 16-position mosaic (4 x 4 grid) of ISAAC pointings : at each
pointing, a series of images were taken in each of the near-infrared J s -
(centred at 1.24 µm wavelength), H- (1.65µm), and K s - (2.16 µm) bands. North
is up and East left.
The total integration time for each pixel in the mosaic was 1200, 300, and 300
seconds in the central 4.5 x 4.5 arcmin region, and 200, 50, and 50 seconds in
the outer part, in J s -, H-, and K s - bands, respectively. The seeing FWHM
(full width at half maximum) was excellent, at 0.38, 0.36, and 0.33 arcsec in J
s, H, and K s, respectively. Point sources are detected in the central region
at the 3-sigma level (brightest pixel above background noise) at 22.6, 21.3,
and 20.4 magnitudes in J s, H, and K s, respectively. These limits imply that a
1 million year old, 0.075 solar-mass object on the star/brown dwarf boundary
could be detected in M16 through roughly 15, 20, and 30 magnitudes of visual
extinction at J s, H, and K s, respectively.
After removal of instrumental signatures and the bright infrared sky
background, all frames in a given band were carefully aligned and adjusted to
form a seamless mosaic. The three monochromatic mosaics were then scaled to the
cube root of their intensities to reduce the enormous dynamic range and enhance
faint nebular features. The mosaics were then combined to create the
colour-coded image, with the J s -band being rendered as blue, the H-band as
green, and the K s -band as red. A total of 144 individual 1024 x 1024 pixel
ISAAC images were merged to form this mosaic.
The Crab Nebula in Taurus
This photo shows a
three colour composite of the well-known Crab Nebula (also known as Messier 1),
as observed with the FORS2 instrument in imaging mode in the morning of
November 10, 1999. It is the remnant of a supernova explosion at a distance of
about 6,000 light-years, observed almost 1,000 years ago, in the year 1054. It
contains a neutron star near its center that spins 30 times per second around
its axis (see below).
In this picture, the
green light is predominantly produced by hydrogen emission from material
ejected by the star that exploded. The blue light is predominantly emitted by
very high-energy ("relativistic") electrons that spiral in a
large-scale magnetic field (so-called synchrotron emission). It is believed
that these electrons are continuously accelerated and ejected by the rapidly
spinning neutron star at the centre of the nebula and which is the remnant core
of the exploded star. This pulsar has been identified with the lower/right of
the two close stars near the geometric center of the nebula, immediately left
of the small arc-like feature, best seen in ESO Press Photo eso9948. Technical
information: ESO Press Photo eso9948 is based on a composite of three images
taken through three different optical filters: B (429 nm; FWHM 88 nm; 5 min;
here rendered as blue), R (657 nm; FWHM 150 nm; 1 min; green) and S II (673 nm;
FWHM 6 nm; 5 min; red) during periods of 0.65 arcsec (R, S II) and 0.80 (B)
seeing, respectively. The field shown measures 6.8 x 6.8 arcminutes and the
images were recorded in frames of 2048 x 2048 pixels, each measuring 0.2
arcseconds. North is up; East is left.