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We are trying to determine the isophots in elliptical galaxies in order to check De-Vaucouleurs law. To do so, we want to convert the data from a FITS file to Excel and analyze it using Excel math capabilities. Does someone know how to make such a conversion?

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Yes, NASA's FTools software contains a program that will do this for you. Go to the FTools website and download a copy of the HEATOOLS. You want to specify that you want the Fimage package on the download page. Since you're running windows, you'll proabably need to download the PC-Cygwin package and install Cygwin as well as there is no native Windows versions. Alternately you can try the FTools through NASA's online interface called WebHera.

In either case the tool you want to use is called fimgdump this will dump an image into an ASCII text file that you can then import into Excel.

Of course if you want a whole suite of image analysis software, I strongly recommend looking at IRAF. It is a old, but well tested and still widely used astronomical software data analysis package.

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Good answer, and I'll repeat your IRAF suggestion - it's going to be much better for most analysis. – spencer nelson Jun 9 '11 at 15:42

If you only have a few files to convert, and you don't want to install software yourself, the CDF group at GSFC offers a web service that will convert from FITS to ASCII, which can then be imported in Excel:

If you have more to convert, and you're willing to do a little programming, there's a WSDL description to generate a SOAP client. They also have already compiled applications to do some of the conversions, but you'd have to take the FITS -> CDF -> ASCII route to use those:

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Thanks guys. I'll be checking those two. I was combing the web and found few additional sights. The next one offers a list of "FITS I/O Libraries": I already tried opening a FITS file with MATLAB. It created a new int16 array which I used to create 3D meshes of NGC5921. You can view them here:

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Alon, did you know you can edit your original question body? This allows you to keep it up to date with any progressions / further information you might come across; this post is an excellent candidate for a question update and it would be great if you would take the time to edit it in. – Grant Thomas Jul 8 '11 at 19:56

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