Re: Computing hour lines for horizontal sundials

Hi Bryan, The "9" in "9.11943" can't be right for any reasonable "log" of "tan", so it's likely a misprint. The "log" than Waugh would likely be using is the common log, LOG10, rather than the natural log we mostly use these days. And indeed LOG10(TAN(7.5)) is −0.8805708975, which is "-1 +

Re: Time problem

Hi Ross, Are you making Time Zone adjustments?. When I start Stellarium, by default it uses my own time zone even if I change location. I have to go to the Plugins and explicitly set a time zone. I imagine you should be working in the local time of Milan, which I estimated roughly at (9.2

Re: Zero magnetic declination at Greenwich

What a coincidence. Just this morning I picked out of my pile of "read one day" books, a book called "Electricity and Magnetism", fifth edition, by S. G. Starling, dated 1929. I happened to be browsing the chapter on Terrestrial Magnetism ... and then your email popped up. The chapter has a

RE: huit nuits [SEC=UNOFFICIAL]

Hi Jos, Your interesting question has been asked on the Internet before: http://ask.metafilter.com/108865/eight-night-ocho-noche-huit-nuit-acht-nacht-otto-notte-oito-noite It appears (from the above link) that there is no link, apart from the fact that all these languages are

RE: Using the moon to find south [SEC=UNOFFICIAL]

HI Steve, I think I can answer this one approximately. The maths is also beyond me, but we can get an intuitive answer without causing too much brain strain. The first point to remember is that both the Sun and the Moon travel on paths nearly along the Ecliptic. The Sun sits exactly on the

RE: Is East/West always at exact 'right-angles', to North/South? [SEC=UNOFFICIAL]

Hi Douglas, I realise your question about the wind was a for discussion type question, but it seems to imply a fallacy. The atmosphere and the earth are part of the same system and rotate together, so if everything was static there would be no friction between the atmosphere and the surface of

RE: Eratosthenes [SEC=UNCLASSIFIED]

Hello Axel, I think you have made a mistake with the number 40231.264 (miles?). If you take the formula for size of a latitude degree, as you stated: dx/d theta = 111.133+0.559*cos(2*theta) km per degree latitude if we integrate this formula with respect to theta from 0 to 360 X =

RE: Where it wil be sprig equinox, at noon [SEC=UNCLASSIFIED]

Hi all, to be pedantic, just to make it sound like I understand this discussion, I think it takes about 43 minutes for light to get here from Jupiter (plus or minus 8 minutes depending on whether it is opposite the Sun from us or not). Cheers Hank Adelaide, Australia

RE: sun position [SEC=UNCLASSIFIED]

* pi * (n - 1) / 365.25 declination = 0.37835994 + 23.264303 * Cos(t + 3.324439) + 0.38088907 * Cos(2 * t + 3.271604) + 0.17119315 * Cos(3 * t + 3.67194) End Function Rem Equation of Time in minutes Rem Regression Equation derived by Hank de Wit from Meeus' astronomical formula Function

RE: varying speed? [SEC=UNCLASSIFIED]

/Kepler's_laws_of_planetary_motion Many regards Hank de Wit Adelaide, Australia -Original Message- From: sundial-boun...@uni-koeln.de [mailto:sundial-boun...@uni-koeln.de] On Behalf Of Brent Sent: Friday, 25 March 2011 11:03 To: Sundial List Subject: varying speed? Hello again; I read this at: http

RE: varying speed? [SEC=UNCLASSIFIED]

I meant angular momentum, not just momentum. Sorry. -Original Message- From: sundial-boun...@uni-koeln.de [mailto:sundial-boun...@uni-koeln.de] On Behalf Of Hank de Wit Sent: Friday, 25 March 2011 11:23 To: Sundial List Subject: RE: varying speed? [SEC=UNCLASSIFIED] Hi Brent, Indeed

RE: The Jacobs Glass Sphere Dial [SEC=UNCLASSIFIED]

Hi all, Kevin is quite right in his identification, except to say the name of the instrument is a Campbell-Stokes sunshine recorder. It is still actually used - in Australia (Bureau of Meteorology) at least. ... And yes, changing the card everyday is boring ;-) Regards Hank de Wit

RE: Shropshire Sundials And Google Earth [SEC=UNCLASSIFIED]

Hi Thomas, You might not get the complete experience, but you can see Phil's locations and photos using Google Maps. Go to Google Maps, http://maps.google.com An in the Search Maps bar paste the URL, http://www.shropshiredials.net/doc.kml Hope this helps. Cheers Hank de Wit Adelaide

RE: 1334? or !434 [SEC=UNCLASSIFIED]

sites: http://www.kenspy.com/Menzies/ http://www.1421exposed.com/ etc. Regards Hank de Wit Adelaide, Australia From: [EMAIL PROTECTED] [mailto:[EMAIL PROTECTED] On Behalf Of Roger Bailey Sent: Friday, 29 August 2008 14:33

RE: Mystery object [SEC=UNCLASSIFIED]

Hi all, Yes, that is exactly what it is, a Campbell-Stokes sunshine recorder. And yes they are still used by Weather Services. At least we still use them here in Australia at the Bureau of Meteorology. Basically a curved piece of chemically impregnated cardboard is placed in the holder

Re: Lat-long lists

How about: http://www.flightsimdownloads.com/ezlandmark/ezdatabase.htm (top page) and then: http://www.flightsimdownloads.com/pub/EZ-Landmarks.dat(small database 1.6MB) http://www.flightsimdownloads.com/ezlandmark/EZ-Landmarks.dat (big database 6.4MB) Or

RE: Precise EOT Program - Comments and a correction

de Wit Regional Computer Manager Bureau of Meteorology, SA ph: 08 8366 2674 Email: [EMAIL PROTECTED] -

Re: Precise EOT Program - Comments and a correction

At 06:59 AM 16/06/2003 +0200, you wrote: Hank de Wit wrote: However, the method of simple differences introduce a 12 hour phase error so we would be better off producing the differential dEOT/dt. As the fourier approximation is linear this can be done with high school calculus. I've

Re: Precise EOT Program

suggestions. John John L. Carmichael Jr. Sundial Sculptures 925 E. Foothills Dr. Tucson Arizona 85718 USA Tel: 520-696-1709 Email: [EMAIL PROTECTED] Website: http://www.sundialsculptures.com - Hank de Wit Regional Computer Manager Bureau of Meteorology, SA ph: 08 8366 2674 Email: [EMAIL

Fwd: Re: Calling AUSTRALIA - and Southern Hemisphere 'Distributors' wanted

552250. E-mails to: [EMAIL PROTECTED] or [EMAIL PROTECTED] Hank de Wit Regional Computer Manager Bureau of Meteorology South Australia mailto:[EMAIL PROTECTED] ph: 08 8366 2674

Re: Analemma Stuff

of the solstices, or equinoxes? I'm sure there is a good reason, but I haven't been able to think of it. Maybe it has to do with indexing the clock to sidereal time, and not to sun time. Any takers? Bill Gottesman Burlington, VT Regards Hank de Wit Adelaide Australia 34.9231S 138.6206E B[EMAIL

Re: graphic conversion

. When it appears nicely on the screen press the PrtSc button. This will save the image to the clipboard. Now run your favorite Paint/Image program and paste from the clipboard. Trim the image down to the equation and save the result as a gif file. Regards Hank de Wit Adelaide Australia

SCHMOYER SUNDIAL

Hi all, I have been reading the discussion on the Schmoyer Sundial with interest. Would it be easy to Southern Hemispherize it? Regards Hank de Wit Adelaide Australia B[EMAIL PROTECTED]/B

Re: (Off topic) Left or Right?

ha. Troy But shouldn't the stronger hand be on the wheel ;-) Cheers Hank de Wit Regional Computer Manager Bureau of Meteorology South Australia mailto:[EMAIL PROTECTED] ph: 08 8366 2674 http://www.sa.bom.gov.au/~hdewit (INTRANET access only)