Presumably, you have approximate coordinates for the object.
Go to the SIMBAD database and search by coordinates (Coordinate Query). http://simbad.u-strasbg.fr/simbad/sim-fcoo
You might want to broaden the search radius to say 2 degrees. Then sort the objects by type (select an arrow under Otype). The PNs should all group together. Will probably have all the NGC and IC PNs but not sure how all-inclusive the database is.
I checked at the first site after converting to Galactic Coordinates and it is not listed there.
I can only see it in HA an NII not OIII. It is very dim 20 mag or dimmer. It does not show up on DSS-2-red. It is a nice annulus about 90'' outer diameter. It is not visible in a deep RGB.
Odd that it should not show up in OIII, which is normally typical of PNs. Try here: http://www.blackskies.org/imageidx.htm Turns out there is an exclusive set of peeps finding these things.
Nothing that matches its position. I am sure it is an undiscovered PN as the foreground stars mask the very faint HA/NII signal. Dust could be attenuating any OIII signal. It is only the 3nm filters and fast optics and low noise camera that have revealed it. Four hours of exposure in 3nm NII also helps.
Nothing that matches its position. I am sure it is an undiscovered PN as the foreground stars mask the very faint HA/NII signal. Dust could be attenuating any OIII signal. It is only the 3nm filters and fast optics and low noise camera that have revealed it. Four hours of exposure in 3nm NII also helps.
In the process of working out how to report it and get it confirmed.
I checked all the data I have. It seems that there are quite a few stars that are in front? of the HA/NII ring and mask its existence. It was only the 3nm filters that attenuated these stars enough so that the ring of the PN was more obvious.
I can just see it on the DSS images because I know it is there.
Bert,
I made enquiries with CDS on your behalf....just received the following reply:
First, you should check that the object is not yet listed in a known list of Planetary Nebulae. You can search for example SIMBAD by coordinates and see if a known object is found : http://simbad.u-strasbg.fr/simbad/sim-fcoo
Also, you can check in a catalogue of known planetary nebulae in VizieR, for example : http://vizier.u-strasbg.fr/viz-bin/VizieR-3?-source=V/127A
You can use the Aladin sky atlas : http://aladin.u-strasbg.fr/java/nph-aladin.pl?frame=downloading
And check if the object is visible in other Halpha surveys (e.g. Image Servers> Others> Supercosmos Halpha)
I also CC this mail to Prof. Parker who has extensive knowledge of planetary nebulae discovery, and can probably assist you further. I am not sure the IAU Astronomical Telegrams are relevant for announcing PNe discoveries http://www.cbat.eps.harvard.edu/index.html
Best regards,
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Sebastien Derriere