Active Galaxy NGC 3079 and the Double Quasar

clic for 50% size 1782 x 1321 (340 kB)


About this Image

The active galaxy NGC 3079 in UMA in approx. 50 million light years distance has got special attention due to its huge bubble of gas that bursts off the galactic plane, checkout the HST report: here.

A second very interesting object in the top right part of this image is the lensed Quasar Q0957+561, the first example of a gravitationally lensed object.
In the optical light, Q0957+561 appears as two point images of roughly 17 mag, separated by 6.1". The strong X-ray radiation is transferred by the strong redshift to UV and blue, so being responsible for the blueish color.
The spectra of the two quasars reveal both redshifts to be at z = 1.41, corresponding to a distance of approx 8 billion light years.
The lensing galaxy at z = 0.36, just visible in the HST image is part of a galaxy cluster, being responsible for the big separation.
Especially remarkable detailed observations indicated that the 2 light curves are shifted in time by about 417 days relative to each other!
Another example of a multiple lensed Quasar is the Einstein Cross.

References: 1, 2, 3, 4.

North is up right.
Below you see a crop on NGC 3079 in 40/80% size.

Even below you find a crop on the Double Quasar in 80% size with a Hubble image insert showing the faint lensing galaxy.

clic for 80% size 1111 x 844 (140 kB)



Technical Details


16" cassegrain in secondary focus at f/10

Mount MK-100 GEM
Camera SBIG STL-11000M at -25C, internal filter wheel
Filters Astronomik LRGB
Date Apr 14, 2005.
Location Wildon/Austria
Sky Conditions mag 5 sky, raw FWHM 2.5" half Moon high up, temperature 8 C
Exposure L:R:G:B = 60:30:30:30 minutes (15-minute sub-exposures for RGB, 10 min subs for L),
Processing Image aquisition in Maxim, image calibration, aligning, DDP in ImagesPlus; color balance, curves, unsharp mask in Photoshop; Noise reduction by Neatimage;