ASASSN-21gk in sagittarius - spectra urgently required !

Information about outbursts of eruptive stars, Be activity, ...
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Robin Leadbeater
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ASASSN-21gk in sagittarius - spectra urgently required !

Post by Robin Leadbeater »

https://groups.io/g/spectro-l/topic/asa ... t/82501723?

Originally suspected to be a gravitational microlensing event the light curve over the past week has been varying rapidly in an erratic way
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LHIRES III #29 ATIK314 ALPY 600/200 ATIK428 Star Analyser 100/200 C11 EQ6
http://www.threehillsobservatory.co.uk
Robin Leadbeater
Posts: 1926
Joined: Mon Sep 26, 2011 4:41 pm
Contact:

Re: ASASSN-21gk in sagittarius - spectra urgently required

Post by Robin Leadbeater »

A spectrum has now confirmed it as an "ordinary star" so the source of the variability is unclear.

https://www.astronomerstelegram.org/?read=14593

A series of spectra covering a period of variability could be interesting. (The clouds returned less than a minute after I got the star on the slit of the ALPY600 when it finally cleared the rooftop at 16 deg altitude). Although extremely noisy, the spectrum was also consistent with the "normal star" description)

Cheers

Robin
LHIRES III #29 ATIK314 ALPY 600/200 ATIK428 Star Analyser 100/200 C11 EQ6
http://www.threehillsobservatory.co.uk
Robin Leadbeater
Posts: 1926
Joined: Mon Sep 26, 2011 4:41 pm
Contact:

Re: ASASSN-21gk in sagittarius - spectra urgently required

Post by Robin Leadbeater »

Very low from here but I tried it again. Here it is in the BAA database overlaid on Pickles G0v
https://britastro.org/specdb/data_graph ... _id=p_g0v
(One of the most frustrating observations I have tried to make. It skimmed along the roof line just arcminutes below it for over an hour before it finally popped up just as the sky was starting to brighten.) It was still at air mass 3.5 and there was thin cloud so the SNR is poor but consistent with the type reported previously (late F /early G)
https://www.astronomerstelegram.org/?read=14593


Cheers
Robin
LHIRES III #29 ATIK314 ALPY 600/200 ATIK428 Star Analyser 100/200 C11 EQ6
http://www.threehillsobservatory.co.uk
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