Pan-STARRS comet spectrum

[Christian Buil]

Here a typical Na flash observation during lastest OHP spectroscopy
course (August 2012).



The flash is clearly visible, but relatively faint. I have often observed this,
but always with an equivalent intensity. Note that the phenomenon is rapid.

The intensity can be variable. but in Paolo spectrum, the
Na emission is very strong. I am still convinced that Paolo
spectrum shows a true comet Na extended emission.

Christian

[Martin Dubs]

Hi Paolo,

I am glad you had the opportunity to make a control measurement of the sodium flash. I believe now that you previously observed an extended Na emission around the comet. Your latest experiment showed the sodium flash around the expected time, but too weak to explain by itself the comet spectra background.

Best regards, Martin

[Paolo Berardi]

Hi all, thanks for your feedback! Na flash shown by Christian is very similar to what I have observed (perhaps a little in advance respect to same twilight phase). This is an animated sequence of 60 sec frames I captured on 14 april:



Anyway I'm not an expert, first time I hear about sodium flash was during OHP2012. I read there are several causes contributing observed effects. I wonder if other amateur never caught flash of different intensity.

On 21 march, in addition to the spectrum I showed here, I was able to take a few frames from UT 18:29 (unfortunately between clouds) with the slit placed farther from the nucleus. I use them in a correlated slit-view and 2d spectra (Na "slice" spectrum is superimposed to slit view) to try to extrapolate sodium tail direction:



Clear sky!
Paolo