To download these data:
Right click on the link above and use option "Save Link As..."
to save the file to a preferred location on your computer.
Use Winzip on a windows machine, or unzip on a
linux machine to unpack the files.
This will unpacked 2 fits image files into your preferred directory.
These fits files are B-band and Halpha images of the spiral
galaxy M81 (=NGC3031), which can be used with the
self-test exercise described in this section.
Each one is about 20 megabytes in size, when unpacked.
Last Updated on 30/11/16 by AES