ISAAC spectrum of the centre of Centaurus A

Two wavelength regions of one of the infrared ISAAC spectra of the center of Centaurus A. The direction of the long spectrograph slit is vertical and the dispersion (wavelength) direction is horizontal; longer wavelengths are towards the right. The two emission lines shown originate in singly ionized Iron ([FeII]; rest wavelength 1256.68 nm) and in Hydrogen (Paschen-Beta; 1281.81 nm) and both are clearly tilted. This is due to the rapid rotation of the accretion disk surrounding the supermassive black hole in the center of the galaxy. The light from the receding edge of the disk is Doppler-shifted towards the red (to the right) and the light from the part of the disk approaching us is shifted to the left. This may be better seen in the inserted enlargements. Therefore the inclined disk shows a tilted spectrum. These motions may be represented in a rotation curve, cf. ESO Press Photo eso0109. There are other emitting areas above and below the nucleus, especially in the Paschen-Beta line. 

Credit:

ESO

About the Image

Id:eso0109b
Type:Observation
Release date:8 March 2001
Related releases:eso0109
Size:2922 x 1797 px

About the Object

Name:Centaurus A
Type:• Local Universe : Galaxy
• Local Universe : Galaxy : Component : Central Black Hole
• X - Galaxies
• X - Quasars & Black Holes
Distance:13 million light years

Image Formats

Großes JPEG
1.8 MB
Screensize JPEG
320.9 KB

Wallpapers

1024x768
479.9 KB
1280x1024
698.6 KB
1600x1200
937.4 KB
1920x1200
1.1 MB
2048x1536
1.3 MB

Colours & filters

BandWavelengthTelescope
Infrared
FeII
1.256 μm Very Large Telescope
ISAAC
Infrared
Pa-beta
1.281 μm Very Large Telescope
ISAAC

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