Instrument

12.5" RCOS @ ~ f/9 (2880 mm fl) at 0.64 arcsec/pixel. Shown at 1.03 and 1.16 arcsec/pixel.

Mount

Paramount ME

Camera

SBIG STL-11000 w/ FW8 filter wheel & AstroDon Gen-2 LRGB filters.

Acquisition Data

5/10/2016 to 6/4/2016 Chino Valley, AZ.  with CCD Commander & CCDSoft.  AOL guided

Exposure

eXcalibrator RGB ratios are 1.00, 0.96 & 1.02

Software & Processing Notes

• CCDSoft, CCDStack, PixInsight, Photoshop CS6.

• eXcalibrator v5.0 for (g:r) color balancing, using 43 stars from the SDSS-DR9 database.

• CCDBand-Aid to repair KAI-11000M vertical bars.

• CCDStack to calibrate all sub exposures and create the RGB image.

• PixInsight to register, normalize, data reject, combine the luminance sub exposures, gradient removal, non-linear stretching with HistogramTransformation and to create the LRGB image. PI's HDRMultiscaleTrans was used to enhance galaxy core detail.

• PhotoShop for the final touch-up.

Comment

North is to the left. The galaxies are shown rotated 80° counterclockwise.

From top to bottom, the image shows galaxies IC 3841, IC 3481A and IC 3483. Their respective distances are about 326, 336 and 20 million light-years, toward the constellation Virgo.

A luminous bridge connects IC 3481 and IC 3481A. A larger looping plume extends about two thirds of the way to IC 3483. A photograph, taken with the Palomar 48-inch Schmidt telescope, seems to show the plume extending fully to IC 3483. However, red-shift data indicate that IC 3483 is in the foreground and this is likely a random alignment.

At the upper right-hand corner, of the wide-view, is the galaxy NGC 4503. As a member of the Virgo cluster, it is cataloged as VCC 1412.

The wide-view image also has over 2000 visible galaxies and eleven quasars.  The most distant QSO's z value is 2.87.  This gives a light travel-time of about 11 billion years.