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Dr Paul Leyland
ParticipantMy mistake too — the object is (102550) 1999 UY17 — I failed to cut and paste the final digit.
I need to check other images of U Leo (there are hundreds) but most of them are properly centred and unlikely to show the region well.
When I return to LP more images can be taken; deeper too. If it is a star it’s quite likely to be brighter than 22.0 at minimum.
Dr Paul Leyland
ParticipantYup. As I said, the MPC knows nothing. The nearest is (102550) 1999 UY1, several arcminutes away and V=19.2
Dr Paul Leyland
ParticipantWhere does manipulation start though ? For example I would venture to suggest almost every deep sky, comet and planetary image in the gallery has had undocumented processing which affects the scientific value (non linear stretch, sharpening, noise reduction star elimination etc etc). As a science based organisation though contributors should welcome challenge and be able to supply the raw data if required. (With the new website there doesn’t appear to be any simple way to make contact with other members any more though)
Cheers
RobinHallelujah!
Pretty pictures are, well, pretty but the original data should always be easily available upon request.
For the avoidance of doubt: I keep all the subs which I subsequently process, whether or not the result is published.
Dr Paul Leyland
ParticipantI don’t have a Unistellar or the like and have no interest in getting one. Consequently no great research into your question has been done.
However, https://www.aavso.org/unistellar-evscope might prove an interesting and/or useful starting point.
Paul
Dr Paul Leyland
ParticipantThose hitting your hand are either absorbed (converted to heat) or reflected. Longer wavelengths are preferentially reflected than shorter ones which is why your skin looks reddish rather than greyish.
Dr Paul Leyland
ParticipantThe photons hit a receptor in the retina (not the nerve directly). They are absorbed and their energy causes a chemical reaction. A long chain of subsequent reactions eventually reach the brain.
The photoreceptor is slowly (hence a long time taken for dark-adaption) returned to its initial chemical state, with the photon’s energy ultimately converted into heat.
An explanation in terms of QED would not be illuminating!
Dr Paul Leyland
ParticipantHmm, I now appear to be Dr Paul Leyland.
Though I admit to having been doctored, I use the title only to impress the impressionable.
No worries. Perhaps there are impressionable people reading this.
Dr Paul Leyland
ParticipantHmm. I measure the position of the nucleus as 06:20:55 +78:10:46.
There is a g=21 star at that position named EDR3-1140862546405873664 and a 15th magnitude star nearby in a whole bunch of catalogues, but I can’t find any catalogued galaxies.
There is also an IR source in the AllWISE catalogue J062057.74+780931.9 but no details other than the magnitude in various bands.
What a curious state of affairs, because it is clearly a large and bright object.
Added in edit: perhaps it isn’t a galaxy. Could it be an especially bright bit of IFN?
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This reply was modified 1 year, 8 months ago by
Dr Paul Leyland.
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This reply was modified 1 year, 8 months ago by
Dr Paul Leyland.
Dr Paul Leyland
ParticipantCaveat Lector!
I clicked on theSeqPlot link in a Firefux browser under Linux. It started creating an unlimited number of new tabs and I had to kill the browser to stop it.
Caveat Lector!
Dr Paul Leyland
ParticipantI made that comment.
https://app.aavso.org/vsp/ is the entry point. After filling various boxes, https://app.aavso.org/vsp/chart/?star=AE+And&scale=F&orientation=ccd&type=chart&fov=18.5&maglimit=20.0&resolution=150&north=up&east=left&other=all produces the chart which I use for my favourite variable.
https://app.aavso.org/vsp/chart/?ra=01%3A12%3A32.10&dec=65%3A43%3A21.0&scale=D&orientation=ccd&type=chart&fov=90.0&maglimit=14.5&title=Random+bit+of+sky&resolution=150&north=up&east=left
shows you the result of typing in specific coordinates rather than the name of a VS. This form is useful for finding solar system objects or distant galaxies as well as exoplanetary host stars.Dr Paul Leyland
ParticipantMy apologies. A cut & paste error which I failed to spot. Thanks for posting the correction.
Dr Paul Leyland
ParticipantThanks Alex.
I really regret not being to get along. I had intended to but events transpired against me.
Dr Paul Leyland
Participant(I’m slowly developing cataracts, and extraneous light impairs my viewing).
Alex – The Commission for Dark Lecture Theatres
I am not developing cataracts, AFAIK, but I whole-heartedly support this viewpoint.
Might future organizers take note?
Paul
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This reply was modified 1 year, 9 months ago by
Dr Paul Leyland. Reason: Qutoed smiley turned out to be absolutely enormous, so I deleted it
Dr Paul Leyland
ParticipantI’d go for the cover approach: compensation not eradication. Not sure whether copper causes snails actual harm or just mild discomfort and consequent deterrence.
My problem isn’t webs but gecko shit. Again, all I do is cover up and sweep away anything left behind.
Both spiders and geckos do a wonderful job at keeping insects under control and I actively encourage them to live with me.
Dr Paul Leyland
ParticipantMaybe I’m wrong, but I remember my mother always telling me: dear son, old stuff dies in the house of fools
The Northumberland refractor in Cambridge is still in regular use. I have used it myself and it is a fine instrument.
The 12″ Northumberland was built in 1834, so pre-Victorian.
The 1864 Thorrowgood is also a fine scope. That one is only 8″ aperture.
I have also looked through a 17th century refactor, an exhibit in the Museum of the History of Science in Oxford. The roof of Blackwell’s bookshop was clearly visible through a conveniently placed window.
Some stuff has to be extremely old before it dies.
Dr Paul Leyland
ParticipantIt was fun to watch and some of those observing from the ground did quite well too…
https://twitter.com/fallingstarIfA/status/1574583529731670021?s=20&t=bSNlZJgGJmZCFPEEcFqEvA
3 tonnes of TNT appears to have made a pretty impressive cloud of debris.
Well, it is (or was) a loosely bound rubble pile according to the images returned so perhaps it is not too surprising that a lot of rubble was thrown out.
Dr Paul Leyland
ParticipantInteresting. It seems to tally with my experience of the last four years in La Palma. Los Llanos is below my horizon, though still visible because I am at a significantly higher altitude, but has become markedly brighter. Everywhere else is much the same. I was mildly surprised to see a hint that my sky may have become slightly darker.
A Major problem for me is the increased frequency of calimas, the local term for Saharan dust clogging the atmosphere.
Dr Paul Leyland
ParticipantI have a planetary image in the gallery taken with a 2.2mm f/1.8 refractor …
https://britastro.org/observations/observation.php?id=20191209_191900_36b00eba365581f4
Perhaps this is cheating, but it is still a refractor telescope by essentially all definitions.
Dr Paul Leyland
ParticipantI am impressed!
Real science being done.
Dr Paul Leyland
ParticipantAs expected. Opened up the observatory at sunset and took a few snapshots of the moon. By the time that the sky was half-way dark all that could be seen was the moon and a sky full of moonlit cirrus.
Mañana perhaps.
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This reply was modified 1 year, 8 months ago by
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