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Thank you, that is very helpful. Now take a little time to think about some elementary geometry.
The definition of a parsec is the distance at which one astronomical unit subtends one second of arc. A parsec is about 3.2 light years, and Jupiter orbits the sun at a distance of 5AU in 12 years. Seen from a parsec away, Jupiter would be at most 5″ from the sun. A more massive object would orbit more quickly at the same distance, or be further away for the same period, ’tis true, but we’re talking order of magnitude estimates here.
The nearest star, alpha Centauri, is 1.3 parsecs away and although it is a multiple system the separations are many AU and the orbital periods are much more than a decade.
The only one which stands a chance of meeting your requirement is Sirius which is 2.7 parsecs away and where the companion is at most 11″ from the primary; the orbital period is about 50 years. A fair number of people have imaged Sirius B, myself included (see the gallery), but it is far from being an easy object.
Good luck!
If you want to measure stellar movements over a short period of time I would suggest that you start with stars of high proper motion. Barnard’s star is the easiest target and its movement can be measured within a week or two if you are careful. It moves around 11″ per annum, or 1″ per month. Careful astrometry should be good to around 0.3″ with amateur equipment. Again, see the gallery for my animated GIF which shows the movement from one summer to the next.
Paul
Robin posted the above some hours ago. As is my usual habit I clicked on the “8 hours 43 minutes” link on the forum contents page which normally takes me to the last post in the thread so annotated.
On this occasion it took me to the Reply-To: form, the one into which I am now typing. This behaviour was reproducible.
My guess is that Robin’s post is the last one on the page and the javascript has a fence-post error which led it to create a new page.
What do you regard as a “short period”?
What do you regard as “wide”?Hard to give specific advice without answers to those questions.
Thanks Alan.
At least in here in La Palma the temperature never falls below 5C, and that figure only exceptionally. I have experienced 7C on this visit, but that is unusual too and the lowest I have ever encountered. “Here” is Tacande at an altitude of 760m. Up on El Roque it falls well below zero every winter.
I am also fortunate here in having a warm and lit control room, well-equipped with a kettle.
Having spent many hours below freezing outside in the UK, with only a cat on occasion to keep my hands warm (another long story), I know well what you mean.
https://britastro.org/forums/topic/ron-arbour#post-609683
I completely agree.
Daryl wrote in https://britastro.org/forums/topic/moon-solves-hubble-tension#post-609557
Do we have the embryo of a new BAA section the Jaffa Section as clearly there is a lot of research to be done especially with the variation of recipe’s around
The Oxford University Astronomical Society conducted a great deal of research into the physics of the Jaffa Cake back in the 70’s and early 80’s. I can still remember some of the results and perhaps there are other ex-OUAS members of that era who are now BAA members.
I seem to remember that the symmetry of the ground state ensemble was something like quintuplet-N-27/2 with at least four excited states known. The Jaffa Cake is not a fundamental particle in that it has substructure composed of chocons, jamons and cakons, the last of which decay into crumbons.
It is a great pity that this topic came up too late for Heather Couper to contribute. I am certain that she partook in that research.
i never met Ron, as far as I recall, but he did prompt me to submit my image of the globular clusters around M81 as a candidate for a picture of the week. The submission was successful. Thanks Ron!
https://britastro.org/observations/observation.php?id=20181111_015500_44cd9ab1092010e3 contains a reference to https://britastro.org/node/19348 (this is just a specific example of no importance otherwise), which link is now broken. I can easily fix isolated examples in my own pages but perhaps they may be corrected globally with a script? AFAICT, and assuming the old pages are still available in an archive somewhere, a relatively straightforward pattern matching exercise should match old with new URLs.
Priority: MAÑANA
That lead to a fascinating, but rather bizarre, exchange on Twitter. It was noted that “giraffe” could be a unit of mass or of length. I proposed that the “slug” be used as that is a standard of unit of mass. Things got rather silly after that.
https://britastro.org/forums/topic/new-website-feedback/page/3#post-608593
Ah, I thought it must be (relatively easily) possible. Thanks.
It doesn’t look like a link under Firefox (no underlining and no colour change, so I never thought of looking there. A combination of UBD and inadequate documentation perhaps.
Paul
P.S. If I can be assistance please ask.
Second Robin’s post of 1:43 pm.
It is a real PITA not to be able to link to posts to which I am replying.
LazyFocus still doesn’t work despite everything I have tried. The contents of the RAR file are internally inconsistent. At least I now know where to ask for more help, so thanks again.
Ah, the latest RAR file is markedly different from the one of several years ago. I am now rather more hopeful and will report back.
Thanks again.
Moderator: might this portion of the thread be better moved elsewhere, the equipment area perhaps?
Thanks William.
I also can’t find teh PM link. Restoring it would be an extremely good idea IMAO.
LazyFocus: I wil check out your suggestion but I already have LAZYFOCUS.DLL and instructions on how to modify the registry for Win 7. The directory indicated doesn’t exist under Win 10.
Perhaps a fresh attempt might be more successful.
“External Links”. Strongly agree with Robin on this one. I am always forgetting to right-click on external links.
A WIBNI.
Relatively low priority, but still…
The current forum interface tells us how long ago the most recent post was made in each topic. Wouldn’t It Be Nice If we could click on the column heading and be able to sort either most recent first or oldest first?
“Personally I much prefer the format used by most other forums like Cloudy Nights, Stargazers Lounge etc where all posts in a topic appear sequentially with the option to quote and link the specific post being replied to. ”
Seconded.
I also like threaded fora because it is easy to see which response applies to which predecessor. I quoted Robin’s text to make it clear that I anm responding to his as opposed to anyone else further upstream.
Wonderful!
An earlier posting indicates which ones are missing from my collection and I would like to acquire any of those which you may have available. I am in La Palma right now but perhaps we can arrange payment to you and delivery to SWMBO who is still back in the UK.
Please feel free to email me.
Paul
