The Sun shone over Raheny observatory on the morning of March 18th.  The perfect opportunity to test my new spectrograph.  The spectrograph itself is a model 'Spectra L200' produced as a kit by well known amateur spectroscopist and author, Ken Harrison.  The setup is very simple the spectrosope is attached to the scope which is pointed at sunlight refecting from a whiteboard.  This avoids the dangers associated with pointing a very large telescope (or any telescope for that matter) anywhere near the Sun.  The slit of the spectrograph (spectroscope and camera) was then narrowed to 25uM to produce as fine detail as possible in the solar spectra.

The takes 4 frames with this setup to cover the entire visible spectrum.  So what follows is a a description of these four frames beginning around 389nM and ending just beyond 740nM.

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Frame A - 3890 Å (angstroms)- 4970 Å (Click graphic for full res view)

As our Sun is composed primarily of Hydrogen, it is hardly surprising that its spectrum shows large evidence of this.  The H-Balmer series describes the appearance of Hydrogen in our spectrum.  Three of the four H-Balmer lines are to be found in this area of the spectrum  Firstly H-Delta measured at 4100.96 angstroms, then H-Gamma, H Beta at 4861Å.  We can faintly see the signature of singly ionised Calcium at 3933Å and 3968Å These are normally more prominent but not given enough exposure in todays image.  The other noteworthy point is multiple lines caused by Iron (Fe).  We also see the first sign of Magnesium here.

Frame B 4530Å to 5610Å (Click graphic for full res view)

The presence of Iron is also strongly seen here with many lines visible.  The main point of interest here is the magnesium triplet at 5167Å, 5173Å and 5184Å.

Frame C 5390 Å to 6500 Å Å (Click graphic for full res view)

The obvious point of interest here is the fraunhofer D lines comprised of the sodium doublet at 5889Å and 5896Å.  We see some more calcium lines and the odd Iron one too.  As we approach the red end of the spectrum we start to see Telluric lines.  These are not from the Sun at all but caused by absorption by Oxygen in Earth's atmosphere.  I'm not sure what the big line at 6497Å is, I suspect it is another telluric O2 line.

Frame D 6400Å - 7400Å (Click graphic for full res view)

We are know well into the red end of the spectrum and clearly there are some very sharp lines to mention.  The first is the H-Alpha line at 6563.Å  This is the last of the balmer series lines to be seen in our spectrum today.  We see more telluric lines, a very sharp O2 absorption at 6867Å and a lot of lines between 7170Å and 7300Å which are caused by water absorbtion in our atmosphere.  Well I hope you enjoyed getting up close and personal with our closest star.  May you feel these lines shining on your face very soon!