Is anyone attempting to do comet photometry?

Community General Discussion
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And, has there been any interest expressed? I was thinking about distant comets undergoing an outburst (not cause by Sun proximity) and wondered it there might be a use for monitoring. `

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sorry for the interruption - I just spilled water on my keyboard. Anyway, I was thinking back to comet Holmes about 15 years ago which underwent a large outburst as it passed Jupiter. Any thoughts?

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I see the COBS database is up to date so maybe the answer is “no additional need”?

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There might be some value with data done in two different ways. One would be B,V photometry done using a curve-of-growth model that fit the profile much as is done with galaxies, so you’d produce ‘aperture magnitudes’ to various specific surface brightness levels (say, V mag 25 per square arcsec, or similar). Given the known distances, these can be converted to fluxes at different radii in km. A big requirement here would be observations of standard stars on each night bracketing the observations of the comets.
Another thing, probably more valuable, would be narrowband photometry to derive production rates of gases coming from the comets. This would require (probably as a minimum) filters centered on the C2 band near 5200A and another for CN around 3900A, both about 100A wide. You’d also want a ‘continuum’ filter, for which it seems a Sloan r filter is sufficient (not much emission there). Again you’d have to observe standard stars (there are such for the comet emission filters) each night to get the flux levels correct.
A recent example of this sort of thing using the 60cm TRAPPIST-North telescope in Morocco:

https://www.astronomerstelegram.org/?read=17538

\Brian

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There would certainly be astronomers taking spectrometric data from comets measuring the elements in the comet’s tail.