Navi - Glare Vs. Nebulosity

[cloudsweeper]

Recently had a quick look at Navi in Cassiopeia.  (Navi, because an astronaut used it for navigation, or because his middle name was Ivan, or both of these??)

Anyway, there was quite a bit of glare around this bright star - atmosphere, glass, the eye, misting, the usual suspects.  With a UHC filter, the "glare" was reduced, then with an OIII, what remained showed up even better.  So I wondered whether it was really nebulosity immediately around the star.  I know it was not the close nebulae IC 59 and 63.

I'd like to hear others' views/experiences of this effect, thanks!

Doug.

[cloudsweeper]

OK - having a good look at atlases, Sky Safari, etc. indicates no nebulosity around Navi, so it's just down to glare, even with filters!

D.

[scarp15]

Void of nebulosity around this star as far as I know, so yes probably just glare. The two nearby reflection nebulae, would require a very dark sky and no filter. The easiest nebula to see in Cassiopeia is the Pacman NGC 281, use an OIII, again only in a dark sky and very good transparency.

[scarp15]

However, Wikipedia has an interesting account for this star, that is seventeen times the mass of the sun.

Quote; When combined with the star's high luminosity, the result is the ejection of matter that forms a hot circumstellar disk of gas. The emissions and brightness variations are apparently caused by this "discretion" disk. 

[cotterless45]

On some nights the atmosphere makes stars look dreadful . Enough to think that there's something wrong with the scope ! Then you get a good night of transparency and seeing and focussed diffraction discs are back to marbleous!

There are a few binaries that have a nebulous appearance.

Nick.

From Sky Safari,

Gamma Cassiopeiae Nebulae

The radiation from γ Cas is currently evaporating two nearby nebulae, IC 59 and IC 63. The leading edges of these nebula glow strongly in the red light of hydrogen reemitted after the gas has absorbed ultraviolet from the nearby luminous star. The bluish regions behind the front lines are where light is simply being scattered.

[Adapted from STARS by Jim Kaler, Professor Emeritus of Astronomy, University of Illinois]

 

[cloudsweeper]

I did think there was some nebulosity there, especially with the way it responded to the filters.  So thanks folks - it looks as though that has been vindicated, and there is a disc of hot gas around Navi.

Always something to delve further into with astro!

D.

[Stub Mandrel]

My experience of imaging Navi suggests that as well as HII regions nearby, the star is embedded in quite spectacular blue reflection nebulosity, rather like the Pleiades.

Stellarium simulates the nebulosity as much less expansive, probably closer to your visual experience?

[cloudsweeper]

Thanks @Stub Mandrel - more to suggest I saw nebulosity.

I must say, as one who hasn't gone for AP, that your image of the region is utterly, frighteningly, stunningly, breathtakingly beautiful.  Really stopped me in my tracks - thanks!!!

Doug.