Astronomy 350: Unix Lab II: Data Reduction• Note in what follows dont type the ¡¿ brackets.• Login to the moxie lab and from there login to the machne 129.3.17.55 usingssh -X -l < u sername > 129.3.1.55.• Now open up some ”xterms” using the command xterm& from your com-mand line.• Type the following: cp /data/ast350/elana/061102 057 ∗ .fits.• What did this command do?• Type gunzip 061102 057 ∗ .fits. What did this command do?• Type ds9&• Click o k if needed.• Type mkdir test and cd into this directory.• Type cp ../061102 057 . What did this command do?• Type mkiraf and when it asks a question, type xterm.• Now type cl: this is the command to start IRAF, a program to analyze fitsimages.• Type display 0611020575.fits and press return. You may need to pressreturn twice.• You should see the fits image on the ds9 viewer. Move the cursor aroundand see what happens.• You should see the X,Y coordinates of the cursor position change and the”count” change. Play around with it. Take the cursor to a bright/darkspot. What happens?• In iraf, type imstat 061102 0575.fits.• Try and describe what happens.• Use the display command to see what 061102 057 5.f its and 061102 0576.f itslook like.• Type epar imarith and answer the questions. This is asking you parametersfor the imarith command which is a way of doing arithmetic with fits images.1• Aim to store the addition of 061102 0575.fits and 061102 0576.fits into afile called test.fits.• Is test.fits different from the originals? Do imstat to find out.• Try imhist < fitsimage >. What do you think the picture describes?• Now try adding up all the fits images you have into another images test1.fits.• Try subtracting a constant from each image etc.• Examine the header of the fits file with the command imhead.• Become familiar with imarith.• Now you can go on to take a look at the images we got at SCC.• They are in the directory shashi/SCC, sorted by date. Copy them overand take a look.• See if you can examine the header files to find out information about whenthe picture was taken, exposure time, what sort of picture etc.• For a picture with no autodark, see if you can subtract a bias and darkfrom it.Is there any difference in the image?• Investigate if the flats are any good.• See what science-dark/flat looks like compared to the original.• Now go on to the data reduction sheet which you have.• First type cd, then type ln -s /data/ast350/¡username¿ cpapir• Take a look a t whats there. gunzip the files and start working on it followingthe data reduction