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Hmm, I can’t see how to direct message you from the forum interface. He is in Breaston, about 8 miles away from Nottingham.
Please drop me a line at my firstname.surname (at) gmail dot com for his full address.
Now arranged. Thanks James.
Incidentally, how does one send a private message to another member? Anyone know?
Hmm, I can’t see how to direct message you from the forum interface. He is in Breaston, about 8 miles away from Nottingham.
Please drop me a line at my firstname.surname (at) gmail dot com for his full address.
There is no need to postulate expansion of space in order to explain redshifts greater than one, in fact you get z=1 for a velocity of just under 180,000 km/s which is quite modest and probably will be achieved by human artefacts[sic] sometime in the next few thousand years.
I am not sure whether you consider tightly collimated clumps of electrons, positrons and protons as “human artifacts”. I do, because they do not occur naturally as far as I know, especially those of the positron variety.
If you do include such things, we achieved such velocities many decades ago.
If it had the maps, I suspect £1000.
But it doesn’t, so my question remains.
And while I am on the subject: a preview-before-posting button would be nice too. Four edits in my earlier post could have been avoided …
We are told that BBCodes can be used to format our postings. I am one of those (very few?) weird people who have memorized a few such codes, such as [_i] [_/i] (underlines added for clarity) for italicizing intermediate text. I doubt that there are many other oddities like me. So, two questions:
1) Would it be possible to provide a pointer to TFM for BBCodes for easy reference when posting and/or replying?
2) Is it possible to provide buttons for pointy-clicky encoding of regions of text such as many other fora provide? See http://www.mersenneforum.org for an example where I post rather often if you want to see what I mean.Thanks Andy.
I have no issues at all with the auto-logout feature — I have been professionally employed in the IT security business for well over 30 years — but the other is a WIBNI which could well take time to implement but would also be valuable if it can be done.
The site logs me out after a period of inactivity. That is mildly annoying but nothing more.
What is annoying is when I am logged out when the Forum page is displayed. To contribute I have to re-authenticate (fair enough) but after doing so I am not returned to the previously displayed page.
Can this be fixed?
I don’t (yet) use ASTAP but thanks for drawing it to my attention. I will take a look.
Russ Laher’s Aperture Photometry Tool, APT, is my tool of choice. Written by a professional at the ZTF for professionals and amateurs alike it does a very good job very easily. It produces CSV format output which is easy to convert to a BAA-VSS spreadsheet. A script to do just that is available from me on request.
APT is available from https://aperturephotometry.org/ and there’s a Wikipedia article at https://en.wikipedia.org/wiki/Aperture_Photometry_Tool
A particularly nice feature of APT is that the apertures can be elliptical, so tracking errors can be tolerated better than with purely circular apertures.
For plate solving I use a local installation of astrometry.net with the Gaia DR2 catalogue.
As Comet Section director I like planets that look like comets…
I like comets that look like planets 😉
Most of the small junk out in the solar system like Caliban, Nereid, Quaoar and Makemake would be brilliant comets if they came close enough to us.
On Twitter Martin Lewis asked about this event. The thread is available at https://twitter.com/SkyInspector/status/1520183595167481856
https://twitter.com/richard_e_cole/status/1520217320819507205 suggests that it may have been a fuel dump from Cosmos 2555 as the orbit tallies rather closely.
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.
Thinking about it, if you are prepared to use a robotic telescope and/or travel to the southern hemisphere and are willing to relax your orbital period requirement to 80 years, alpha Cen is also a possibility.
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.
