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I would like the very early ones please. My collection starts (I think) in 198 and is complete to 2022.
The collection is also 4000km from here so I can’t check for sure until I return to the UK in two weeks time.
I remember a similar Y2K bug in a clock display. The coder appended the year to “19”, rather than adding to 1900. On 2000-01-01 the display read 1 Jan 19100.
Takeaway message: character strings are not numbers, even when they look like them.
It is not just a matter of storage. For instance, some years ago one of my Perl scripts contained this
my ($star, $jd, $mag); while (<INPUT>) { if (/^Variable\s+(.*)/) { $star = $1 and next; } elsif (/^(245\d+\.\d+)\tV\t(.*?)\t/) { ($jd, $mag) = ($1, $2); $mag =~ s/\[/</ or $mag = sprintf “%.2f”, $mag; my ($year, $month, $day) = jd2gregorian ($jd + 0.5); printf “%s\t%.3f\t%s\tLEY\n”, $star, $day, $mag; } }Spot the bug.
Nice to know. I started by doing the best I could with the Spanish (I am trying to become fluent in the language) and then switched to Google translate to complete the task.
My phrase was “barely runs”. I did manage to get it to run eventually, but it seems to be much less stable and reliable for me than is reported by those who run it natively. You may have more success.
Paul
In my experience, it is much easier to convert a DSLR image to FITS than it is to persuade Astrometrica to pay any attention to an embedded WCS.
For JPG and PNG files, nova.astrometry.net will convert to FITS and plate-solve for free. There are any number of free apps to convert from RAW format to something more amenable, including FITS. A very quick search on “RAW to FITS converter” dug up several on the first page.
The major problem with Astrometrica, in my experience, is that it runs natively only under Windoze and barely runs under WINE. I don’t trust the photometry very much either. If the source code were available we could check and perhaps enhance, but it isn’t and we can’t.
Other than that, parts of it are excellent and it is likely what I would use, had I not written a script to track on an object moving from frame to frame.
This raises a general point: should we have a playpen sub-forum where would-be posters can check and edit their proposed postings before subsequently copying the final product to its intended place? This facility is quite common on sites which encourage user-generated content.
Such a place would carry a guarantee that nothing placed there would be permanent (admins or a script could periodically flush everything over a certain age, for instance). It would allow people to learn and it would confine (most) uncovered bugs to a harmless place of quarantine.
Mea culpa.
I was trying to find out what may be attached to a post in line with Nick’s earlier attempt.
Pleased to discover a bug, regret having uncovered unfortunate consequences.
Nick and I have recently been discovering what can and can not be attached to forum posts.
The only information provided seems to be that an attachment must not be larger than 4MB.Please could we have a statement of what is allowed and what is not? Experiment seems to show that text files are not permitted.
Thanks,
PaulI have just noticed that cover photo to ‘Atlas if the Moon’ Wood and Collins, shows both the impact crater and the volcano, designated Mairan T, both are shown together with their correct designation. I’m not sure who names features on the Moon, but giving the crater and the volcano much the same name is confusing. I also note the description inside the atlas that refers to the volcano with a crater on top, this could easily lead one to conclude the feature top most on the volcano is an impact crater, but that is not the case.
The Wikipedia article explains that nomenclature is set by the IAU and the convention for naming smaller scale features located close to the principle crater.
Perhaps it might be useful for you to review the article.
Paul, Thank you and I had seen that Wiki reference, but I was after Mairan T, not the lunar impact crater, Mairan, it’s a bit confusing. I’m interested in the lunar volcano, designated as ‘the silicic volcano Mairan’. Interestingly some descriptions give this as an impact crater or crater, but it’s not, more a collapsed volcano caldera.
I quoted the location of Mairan T as given in that article!
The location of Mairan itself is given as 41.6°N 43.4°W in Wikipedia.
Wikipedia to the rescue:
https://en.wikipedia.org/wiki/Mairan_(crater)
has its location as 41.7° N 48.3° W.
Always worth checking with Wikipedia and DuckDuckGo for these sorts of questions.
Apologies for the typo 111.61 when I meant 311.61.
What is that feature and what do you expect to be its coordinates?
Note that 311.61 East is equivalent, in most spherical coordinate systems, to 360-111.61 = 48.39 West.
Trebor
Alas poor Yorlik, I knew him backwards.
Thanks Nick.
Now snaffled. I already have code to do the first two functions and will implement the third based on your suggestion. My version uses Perl and SWarp.
The best compromise, IMAO, is a fork with long enough arms.
Now the disadvantage is that it needs to be much more robust to prevent flexure. I am fairly sure that my fork would be capable with longer arms and is would appear that yours would be too.
All this is way off topic for this place. Perhaps Webmaster could create a new topic in an appropriate place and more the postings there. Please? Pretty please?
Yes, we win some and we lose some. I don’t actually lose very much useful sky as Dec +75 reaches a maximum altitude of 43 degrees and a minimum of 13 degrees from here and I don’t much like doing photometry below 30 degrees altitude unless it is really necessary. I have always really loathed meridian flips.
HL CMa was nice and high in the sky here (just to make you jealous 🙂 — there are advantages to having a low celestial pole — until cloud stopped play. 1 made it V=12.33 tonight.
You guys up in the frozen north have it lucky.
I find it very frustrating that Polaris is only 28 degrees above the horizon from here. Even worse, my fork mount won’t allow pointing at anything above a Declination of 75N or the camera hits the mount. Guess where C/2022 E3 is tonight …
With luck it will be far south enough to give me a chance in a few days but, of course, the moon will then be very near full.
Life, don’t talk to me about life.
Paul
P.S. now the ****ing filter wheel has just packed up and I must go back to the dome to see what needs to be kicked into submission. Almost always a Windoze/USB failure.
Interesting. Radiant sky temperature in La Palma is also about 30C lower than ambient.
I have never seen dew anywhere except inside a SBIG camera after the desiccant needed renewing. That was excusable because it was generally run at -20C.
Perhaps having the scope inside a dome is advantageous from this point of view too.
