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David Strange
ParticipantHello Ed,
Here at the Norman Lockyer Observatory we have a wifi signal that reaches our domes and the surrounding grounds outside. Folks with telescopes set up as well as those imaging from the telescopes in the observatory can transmit their videos/ccd images to our lecture theatre projector via Radmin, Anydesk or Teamviewer, so people can watch in the warm! Sadly, not at the moment because of Covid, but we can still broadcast via Zoom.
David
David Strange
ParticipantHi David,
No freeserve is now defunct. I’ve pm’d you my contact details.
David
David Strange
ParticipantDavid, we can offer to live stream from the Lockyer telescope (6.25″) – the one that Lockyer used to discover Helium on the Sun. We have a good broadband connection at NLO.
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David Strange
ParticipantThanks Hazel, cloudy here for the next few days as well.
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David Strange
ParticipantCompiled from images using 28mm – 300mm lens, 100mm f/6 refractor, 50cm f/4 newtonian from Salcombe Regis & NLO, Sidmouth.
https://www.youtube.com/watch?v=Q35MKbjnWZM
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David Strange
ParticipantNorman Lockyer Observatory members gather for the first time since lockdown for a news bulletin on Comet Neowise for ITV’s News at Ten.
https://m.youtube.com/watch?v=2ciG0yTR6Q4
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David Strange
ParticipantThis is a comparison of raw spectra taken 8 days apart showing depletion of sodium emission but increase in C2 and CN.The comet looks like it has now lost its golden colour and images are picking up more blue/green in the coma perhaps due to this increase?
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David Strange
ParticipantClear here again tonight! Also just realised that my Canon has been imaging at f/27! Wondered why I wasn’t getting the ion tail recorded, hope to do better now!
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David Strange
ParticipantComet Neowise caught in single 20s exp. with Ricoh Theta camera last night
https://theta360.com/s/jOGdKcj6M9KsLhWHUK5I5aqwq?utm_source=app_theta_twitter&utm_medium=social
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David Strange
ParticipantThanks Robin, I thought that was probably the case! So a Sodium tail is back in the running!
Have you got a spectra across the tail yet?
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David Strange
ParticipantHere’s a great image and spectrum by Torsten Hansen using a star analyser and 135mm lens. The sodium tail is much straighter than the dust tail, so would definitely manifest itself towards the left. See lower image here:
David Strange
ParticipantThanks for that link Robin. It looks as though the offset of the Sodium tail is just 3 degrees from that of the main dust tail in the PSI image. Presuming that this image shows south at the top, the Sodium image is offset in a clockwise direction. I have measured Andy’s image and it shows that the red tail is offset approx 17 degrees in an anti-clockwise direction. So I don’t think the red tail is Sodium.
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David Strange
ParticipantThat’s interesting, the colour of this certainly looks redder than sodium. But I don’t see much evidence of NH2 in the Neowise spectrum, but I guess most spectra have been centred on the nuclear region.
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David Strange
ParticipantBeautiful image! I’m guessing it could be due to Na emission in the yellow?
https://britastro.org/node/23206
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David Strange
ParticipantCaught this spectrum of the comet this morning showing bright Sodium line, C2 banding and I’m guessing CN emission on far left? 20 x30s with ASI 183mm and Alpy (binned 2×2 at 2.5A/pixel).Taken with 50cm f/4 Connaught Dome at NLO.
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David Strange
ParticipantSorry, cloudy here in Devon. Could only catch a fleeting glance of Capella every now and again.
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David Strange
ParticipantGreat shot! Yes, definitely there.
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David Strange
ParticipantThanks for that. i am researching Lockyer’s work on sunspots when he projected the sun’s image on to a screen with a slit in it, over which he positioned a sunspot. With his spectroscope receiving the light of the spot, (I guess it was his 7 prism one) he noticed that the spectral lines were widened. This was years before Pieter Zeeman’s discovery of the splitting of spectral lines due to magnetism and Hale’s observations linking sunspots and magnetism.
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David Strange
ParticipantWas the image captured with a reflector or refractor? If the latter, the ring may have been caused by the star showing excess infrared emission hence out of focus with respect to other stars. Advise him to take another image of the same star field, but this time refocus on the star with the ring. If that sharpens then all the others will look like planetary nebulae – proving the point!
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David Strange
ParticipantThanks for the heads up! I caught a spectrum of it last night with an SA100 & C9 30x30s exp.Rotated image 90 deg to avoid galaxy: Think I’ve caught the Si II absorption line at 6127A. Cheers, David
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