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Apparently no spare unbound copy of these three Handbooks was available when the set of Handbooks was originally scanned several years ago. This problem is now overcome, and scans of those three years will be made next week, and added to the website, eventually.
Good news!
A bit of fluff picked up when examining the PDFs: 2014 has 119 pages, which is a rather odd number. All others from 2013 to 2024 inclusive have 120.
Are you sure that the scope is in focus?
The vertical line is usually outside the cross when it is severely out of focus. Otherwise, I have no idea at present.
The other option is to explore Microsoft Teams.
Curiously enough a Linux client is available too.
Unfortunately, it seems that a Microsoft account is required before it is of any use.
To amplify what Jeremy says: I have over sixty thousand images of T CrB taken with a Seestar S50. The size of the data processing task is daunting and automation will be essential. Your proposed system has a bigger aperture and, presumably, a better quality and equatorial mount.
The SS50 has a OSC camera, with its inevitable loss of sensitivity for precision photometry. If you can fit a mono camera and a photometric filter — almost certainly Johnson V — you should be able to do markedly better than a stock SS50.
Paul
Seconded. Anyone can use any of my images taken to date, such as they are, under the CC BY-SA 4.0 license.
`Paul
The other big issue here is copyright. Basically, all outreach presentations will have images whose copyright is owned by the original observers. Your average local society will typically operate on the basis that nobody is going to complain about their images appearing in a talk – but as soon as you start distributing the slides online, you are redistributing people’s work and clearly need consent to do that. Within the BAA this is managed through our T&Cs, which say that any images submitted to sections or online can be reproduced in any BAA publications, but that does not extend to inviting local societies to edit and reuse the images and share them online.
Sorry if that all sounds very negative!
A possibility might be to see if any of the Creative Commons terms and conditions are usable and, if so, insist that an appropriate copyright notice be attached to the material in question before the BAA would host it.
Agreed, copyright can be a minefield with the mines laid in a swamp.
C/2026 A1 (MAPS) is no more, it has ceased to be. Bereft of life it rests in pieces. It is an ex-comet.
https://ccor.nrl.navy.mil/ccor_realtime/CCOR1_realtime_MinBckgnd.mp4 for a video of its demise.
I think that is Venus. Rotated image so north is at top and tried matching objects. Alas Mercury seems to be behind our planet.
Hey, you can see my house from there!
Well, La Palma anyway. Tenerife and Gran Canaria show up particularly well, likely because the former still has snow on Teide which fell from storm Therese whereas the latter, as the name suggests, is the biggest of the Canary Islands. El Roque, on La Palma, also has snow on it which is why La Palma is easily visible despite it being relatively small.
Incidentally, that storm dumped 419mm of rain on me which is about nine months typical rainfall. A significant amount came through the roof and ceiling. 8-(
According to units(1), 1HP = 745.7W and 340kW = 456HP. The discrepancy is a factor of 4.7.
I am prepared to believe that bus engines have become markedly more powerful since the last published measurement made quite a few decades ago. Car and motorbike engines certainly have.
Already mailed Paul. Albondon is relatively close to La Palma (close by UK standards anyway, though still a 2-day journey in each direction) and although shipping would not be cheap, it should not to be too expensive — especially if I rent a van and drive/ferry over there and back myself.
A vacant concrete pad at Tacande Observatory already has power and ethernet laid on. It is big enough to hold a 4m diameter dome.
Arrangements have been made. In the fullness of time a ~4m dome will be planted on that pad ready to host a 0.4m RC telescope.
Sorry to hear about this. I hope the kit finds new worthy homes.
Likewise.
Already mailed Paul. Albondon is relatively close to La Palma (close by UK standards anyway, though still a 2-day journey in each direction) and although shipping would not be cheap, it should not to be too expensive — especially if I rent a van and drive/ferry over there and back myself.
A vacant concrete pad at Tacande Observatory already has power and ethernet laid on. It is big enough to hold a 4m diameter dome.
Paul (another one).
Interesting that no-one has yet picked up my albedo error. The albedo is the fraction reflected, not the fraction absorbed. Multiplying by the WAG of 0.9 is OK, but the albedo is likely about 0.1.
It will be 1360 * 1 / (0.0057*0.0057) = 41.8 MWm/2 assuming the Earth is at 1AU.
Strictly speaking (and one should always speak strictly, especially to animals and young children) the figure must be multiplied by the albedo as some of that power density will be reflected. I have little idea of the true albedo integrated over all wavelengths but a figure of 0.9 may be in the right ballpark. Still a fearsome figure.
Hi Nick,
The fcombine you provided no longer works on my Ubuntu system because the libcfitsio.so.9 library has been updated to version 10. Attempting to re-download your program gave an error.
Any chance of the source code being made available (to me only if you do not want a public release) so that it can be rebuilt as required in the future?
Thanks,
Paul
The only way I could get it to work iss to manually copy/paste the data parameters for each satellite.
Yes, that is exactly what I do. Takes an extra 30 seconds or so, but that is negligible compared with the exposure time needed to reach 20th magnitude or below.
Yes.
Both the MPC and JPL provide ephemerides, though MPC only for the outer satellites. The URLs are https://minorplanetcenter.net/iau/NatSats/NaturalSatellites.html and https://ssd.jpl.nasa.gov/horizons/app.html#/ respectively.
If you wander over to http://www.astropalma.com/Projects/planetary_satellites.html you will see (most of) the images I have taken using these resources. One day, assuming I get a round tuit from somewhere, I will update that page with some more images. A fair number appear in my image gallery here on britastro.org
Have fun!
Paul
I think this has been covered, but unfiltered is definitely preferable to a UVIR blocking filter.
For my part I tend to use unfiltered for time-series work (exoplanets previously, asteroids these days) to achieve the greatest SNR and the fastest cadence. As only the minute to minute variation is of interest there is no great need to have the observed magnitudes be comparable with measurements made by other observers.
When making precision measurements I almost always use a V filter but have been known to submit CV measurements — unfiltered with comparison magnitudes given in Johnson V.
No great need for a filter, in other words, except for red stars as noted above. A filter is nice to have, undoubtedly, but no-one should let expense put them off making scientifically valuable measurements.
One day I really must see if I can find a round tuit down the back of the sofa because there are literally thousands of images on disk which were taken with the Seestar’s OSC camera. Trouble is that all of them need de-Bayering and the green channel measurements transformed to standard V. Another example of where external filters are no needed — the Bayer mask consists of filters which are internal to the detector.
