What are the strange absorption peaks on this solar spectrum?

[BucketOfFish]

I was taking solar spectra yesterday for a Physics lab, and I found this strange phenomenon slightly to the left of the sun. I think it might be a solar prominence, but then again I know absolutely nothing about astronomy. What is it?

(The graph is intensity vs. wavelength)

http://www.imgur.com/FfZxd

EDIT: I can't get the image to show, but the link is http://imgur.com/FfZxd. The absorption peaks are at 760.15 nm and 761.18 nm.

 

[Drakkith]

How far to the left are we talking about here? A few arcseconds?

 

[davenn]

here's the image for easy viewing :)

Dave

 

[BucketOfFish]

Never mind, it turns out it's probably just the cheap spectrometer giving faulty readings. No strange solar phenomena today.

 

[Drakkith]

Never mind, it turns out it's probably just the cheap spectrometer giving faulty readings. No strange solar phenomena today.

No worries! Keep up the experiments!

 

[matt.o]

The features seen at ~690, 720 and 760nm are due to absorption of the sunlight by molecules (water, I think) in the Earth's atmosphere. They are otherwise known as telluric absorption features.

 

[vociferous]

http://en.wikipedia.org/wiki/Fraunhofer_lines

If the spectrographic data is properly normalized and calibrated (obviously it is not), then those would be O2 lines. Now, do you think that molecular oxygen might exist in a G-type star? If not, where might molecular oxygen exist between your telescope and the sun?

Also, looking at the data, I am not convinced the wavelengths are accurate. You should be able to calculate what the peak energy output from the sun is from Wein's displacement law. If the wavelengths are off, then that might be H2O instead of O2. Now, where could H2O exist? In the sun's atmosphere? Probably not.

 

[matt.o]

http://en.wikipedia.org/wiki/Fraunhofer_lines

Also, looking at the data, I am not convinced the wavelengths are accurate. You should be able to calculate what the peak energy output from the sun is from Wein's displacement law. If the wavelengths are off, then that might be H2O instead of O2. Now, where could H2O exist? In the sun's atmosphere? Probably not.

I am not sure if these questions are directed at me, but I'll answer anyway. The wavelength calibration looks okay to me. The Calcium H & K lines appear to be located at their expected positions (393.4 and 396.9nm), as do the Sodium D line (~589nm) and the hydrogen alpha (656.3nm), to name just a few.

Also, the telluric features are labelled in the solar spectrum shown on that wiki page.

 

[vociferous]

I am not sure if these questions are directed at me, but I'll answer anyway. The wavelength calibration looks okay to me. The Calcium H & K lines appear to be located at their expected positions (393.4 and 396.9nm), as do the Sodium D line (~589nm) and the hydrogen alpha (656.3nm), to name just a few.

Also, the telluric features are labelled in the solar spectrum shown on that wiki page.

It was directed at the OP, but I just looked at some spectra of various objects I took last year and I guess I was misremembering the O2 lines being weaker than the H2O lines (except for Saturn, where H2O was almost as strong as O2, which may be partially due to extraterrestrial O2 combining with atmospheric O2).