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Yes, it will be interesting to watch it pass through. SOHO is getting very old now and is living on borrowed time. What will we do when it is gone?
There is indirect and rather weak evidence that some other objects may have interstellar origins but A/2017 U1 (now demoted from cometary status) has direct evidence from its strongly hyperbolic orbit. We’ve never seen anything with this kind of orbit before.
Also, in the “how far south can you see from the Canary Islands” here’s a picture of the top half of Crux on the horizon taken from La Palma.
I have a load of frames of the southern sky taken from a beach in Queensland but I’ve never got around to processing most of them since there was a lot of drifting cloud. They were all taken with a camera on a fixed tripod so the exposures are short. I have a set of Crux and I’ve uploaded one frame here. It did get a nice set of the LMC and this is the only set I have every processed. The final version is here. Timelapses of the rest are here.
Indeed some fantastic images. I particularly like the skyscape ones.
Robin,
Many thanks for all of your help with this. An interesting result and a very steep learning curve for me!
Nick.
We’ve received the calibrated 2D spectrum which was obtained by Richard Miles using the FTN but can’t make much sense of it. One of the FITS files is attached and if anyone has any insight it would be appreciated. According to the FITS header I think the left hand end corresponds to 474.2 nm and the scale is 0.3511 nm/pix. This would put H-alpha at around X=518 but there is no sign of anything there. I need to delve into the FLOYDS documentation but if anyone has any ideas I’d be very pleased to hear them!
Richard Miles tells me that the 2.0m FTN has acquired a spectrum using the FLOYDS spectrograph. The raw data will be processed after the telescope closes for the night. Richard sent me the attached image showing the raw spectrum which doesn’t mean a lot to me at the moment but presumably will make more sense once it is rectified and calibrated. Many thanks to Richard for arranging this.
There’s an interesting article on spectral confirmation of novae here. Any comments from the spectroscopists on this forum would be very useful.
Thanks Robin. If you do get a clear slot it would be worth a try. George imaged it again last night and the object has brightened to around mag 16. Richard Miles has a spectrograph job on the 2.0-m FTN which is currently scheduled for this morning.
Andrew,
They do not remain valid and they probably were not valid even when Wooley made them. I enjoy being under a dark sky and observing from dusk to dawn but where I live the sky is yellow and so I prefer to observe from indoors with a remote telescope (either my own one down the end of the garden) or one on a different continent. To claim that someone who spends a night under the stars is any more or less of an astronomer than someone who has set up and uses an automated telescope system is plainly rubbish. I would extend that to people who use remote telescopes and process and analyze their results.
Life moves on. We all have our own preferences as to how we do our astronomy and all are equally valid. We are amateurs after all so we can decide what we want to do.
Nick.
James,
Thanks. I’ve just got back to the hotel in Kearney. We had quite a long trip to Tryon this morning since the weather prediction for around here was not good. From the messages I’ve received it looks as if many BAA people saw it from various places (Idaho, Jackson and Casper and further down the track).
Two years until the next one!
Nick.
Frustratingly it was mainly cloudy in Chelmsford last light but there were plenty of Perseids around in the gaps. Pictures of a couple of the bright ones are attached.
These days I prefer to operate my DSLR in HD video mode with manual exposure and the ISO fixed at 400 I then adjust the exposure during the eclipse to suit. I use a Megrez 72 and x2 Barlow operating at around f/13. I tend to take my filter off around a minute before second contact and adjust the exposure so that I get correct exposure on the inner corona which is visible even before C2. This leaves an overexposed photosphere but generally works well then for the diamond ring and prominences. You can see an example of this at around 0:25 in to this video. For Baily’s beads You would leave the filter on until C2 and use the same exposure that you use for the thin crescent.
During totality an example exposure for prominences, inner corona and chromosphere at f/13 is around 1/1600 at ISO800 which is what I used for the attached image. This is a raw image just scaled to 50%. This would be good for the diamond ring at C2 and C3 without a filter but you would wind up the exposure to get more corona. Depending on your field of view of course since really long exposures are only worth doing if you have a shorter focal length.
A huge advantage of digital over film is that you can see things in real time using live view so you can adjust exposures to suit the conditions. If this is your first eclipse though I would strongly suggest that you don’t spend too much time imaging but use binoculars and the naked eye to enjoy the view.
It’s in outburst: https://twitter.com/SuperASASSN/status/889934384496640000
Looks a really interesting bit of kit. A kind of hybrid of visual observing and electronic. I expect it would appeal to a lot of people.
Wow, is it really 28 years ago! Yes, I remember the Titan/28 Sgr occultation very well, particularly the astonishing central brightening when light from the star was refracted around the limb of Titan by its atmosphere. I didn’t have any sophisticated equipment then and the attached photo was taken with a camera mounted on the back of a small refractor.
Cassini is a mission very close to my heart. I was there for the launch and will be raising a glass when it dives into Saturn’s atmosphere on September 15.
The orbit is still very uncertain but all the astrometry to date (a 25 day arc) implies that it is near parabolic with a perihelion at 1.8au at the end of 2022 or early 2023. This is much less interesting than if it had been in a shorter period orbit since it probably means the that the comet is dynamically new. Such comets tend to have significant activity far from the Sun but then the underperform as they move into the inner Solar System. Still, it is worth observing this comet if you have the equipment. It is very well placed and you don’t often get the chance to image comets which are 16au away.
