Sunset/Sunrise Calculator

Hello All,

I am looking for a sunrise/sunset calculator (time and compass bearing) to run on my laptop (Win XP). It would need to work without internet connection, in both southern and northern hemispheres.

Any suggestions?

Stewart Skelt said:

Hello All,

I am looking for a sunrise/sunset calculator (time and compass bearing) to run on my laptop (Win XP). It would need to work without internet connection, in both southern and northern hemispheres.

Any suggestions?

Click to expand...

These kinds of programs are used by ham radio operators - particularly those interested in what is called "grey line propagation".

Google under that phrase and you will turn up sources of both programs and "real time" sites.

I use a shareware utility called Moonrise 3.5 that is very good Dead Link Removed

The writer talks mostly about the prgramme's moon related features on his web page, but it also gives you sunrise and set times and azumith for any day and place.

I always check moonrise before a trip, and make a note of the relevant data.


Peter

Bandicoot said:

I use a shareware utility called Moonrise 3.5 that is very good Dead Link Removed

The writer talks mostly about the prgramme's moon related features on his web page, but it also gives you sunrise and set times and azumith for any day and place.

I always check moonrise before a trip, and make a note of the relevant data.


Peter

Click to expand...

Do any of these programs calculate where on the horizon the mon or sun will rise and set?

Bandicoot said:

...but it also gives you sunrise and set times and azumith for any day and place.

Click to expand...

donbga said:

Do any of these programs calculate where on the horizon the mon or sun will rise and set?

Click to expand...

Azimuth = compass bearing

Lee

Here's the film industry standard. It's very accurate and easy to use. I picked up my suunto tandem bor $80

Dead Link Removed
http://filmtools.com/widsof.html
vinny

Best site I've found is from the U.S. Navy. Really great for this stuff. tim

http://aa.usno.navy.mil/data/docs/AltAz.html

I haven't used Windows for a couple of years, so I'm not up on the latest desktop/toolbar widgets for moonrise/set but here's a golden oldie that I used for years: http://astro.nineplanets.org/ice/ice.html

It might be overkill, is a DOS program, puts out tabular data, but it's very accurate (put together by the US Naval Observatory) and will give you positional data for a large number of objects, including all planets, the sun and moon, and many stars, including a list of daily rise/set/azimuth times for as many days as you like up through 2049. You can also generate positional data for any specific date or time, and at intervals you define. It will have a small learning curve, but you will get accurate data tables that you can also print out and use away from the computer.

It's formatted to fit on 4 floppies. You can download and unzip the files on the linked page.

Lee

noseoil said:

Best site I've found is from the U.S. Navy. Really great for this stuff. tim

http://aa.usno.navy.mil/data/docs/AltAz.html

Click to expand...

Posted while I was writing...

That's an online version (a bit pared down on the output) of the ICE program I mentioned.

Lee

Thanks to your question I've finally gotten around to doing something I've meant to do for a long time. I wanted to post sample output from ICE so that you could evaluate it. Since I'm now running linux, I used "dosbox" (an emulator under linux) to run ICE and output a file for the moon in May '07 for an observatory near my location. I pulled the resulting ascii file into openoffice so that I could generate a .pdf file that would hold formatting on a post to APUG. Here is the output you'll get for 31 days of lunar rise and set times starting May 1, 2007. Note that there are some times that are preceded by "f" or "p". This indicates "following" or "previous" day, since each rise/set pairing of the moon can straddle a solar day. The azimuth (compass bearing) for rise and set and the maximum altitude in degrees is in parentheses beside the times for rise/set and transit (crossing a line from N to S through your local zenith).

You can also run the numbers for the moon in tiny increments during a single day to give you alt/az for any time as it crosses the sky (in case you want to calculate exactly where it will be relative to an object in your scene). Be sure to adjust for local magnetic deviation when using a compass to predict the location of the sun or moon. In my location it's currently off by 6.5 degrees to the west of due north.

And for the linux users here, you now can put ICE to use for yourselves.

DOSbox is also available for OS-X users, and the ICE program is so simple I'd expect it to work very well there as well.

I know this isn't as simple as some might like, but it works, it's free, is very accurate, and you can print as far in advance as you like and use it without toting along a computer.

Lee

I've seen Tom Mackie mention a product called "Flights Logistics - Sun Compass". It looks like an interesting product; I'm not sure if it is available outside the UK or not.

http://www.comparestoreprices.co.uk...ded-flight-logistics-sun-position-compass.asp

roteague said:

I've seen Tom Mackie mention a product called "Flights Logistics - Sun Compass".

Click to expand...

If I read the original post correctly, Stewart is looking for something more generally applicable. The item listed could be used south of -45 degrees latitude if you mentally reverse it (substitute S for N), but it's not useful within +/- 45 degrees of the equator. Also, within its working range, it will be accurate within +/- 2 to 3 degrees at best, less accurate if you're not very good at estimating and implementing local magnetic deviation on a rather small compass rose.

In a mountainous setting, where the local horizon can be much higher than the idealized "flat" horizon reported by the "Sun Compass", the actual bearing of sunrise on the local horizon can differ significantly from such an instrument and from computer programs that can't give you an azimuth from non-zero local horizon altitudes.

A Silva Ranger or Suunto equivalent, especially one with an inclinometer feature and an adjustable magnetic deviation setting, would be much more accurate for finding sunrise and set on a local horizon in conjunction with most computer programs. Of course the individual photographer will have to determine how much accuracy is needed or useful for their purpose.

Lee

That is true Lee. I've never seriously looked at it myself, since I live south of 45°. I'm not sure whether it would work for Stewart either; it depends upon what part of Australia he lives. The 45° parallel (Tropic of Capricorn) line runs just a bit north of Alice Springs and pretty well cuts the country in half.

roteague said:

The 45° parallel (Tropic of Capricorn) line runs just a bit north of Alice Springs and pretty well cuts the country in half.

Click to expand...

Robert,

The Tropic of Capricorn is where you place it relative to Australia. However, that's 23.5 degrees south of the equator. (The tropics are defined as the area on earth where the sun can, at some point during the year, be directly overhead. That cycles between 23.5 south and 23.5 north latitudes because of the tilt of earth's spin axis relative to our orbit around the sun.)

45 degrees south is well off the southern coast of Tasmania, placing all of Oz outside the useful range of the "Sun Compass". So the "Sun Compass" would have little utility in the southern hemisphere unless you are at the southern tip of S. America or New Zealand.

It's interesting how skewed our perspectives become in the northern hemisphere. 45 degrees north would be Halifax, Ottowa, Minneapolis, and Salem (Oregon).

Lee

Lee L said:

Robert,

The Tropic of Capricorn is where you place it relative to Australia. However, that's 23.5 degrees south of the equator. (The tropics are defined as the area on earth where the sun can, at some point during the year, be directly overhead. That cycles between 23.5 south and 23.5 north latitudes because of the tilt of earth's spin axis relative to our orbit around the sun.)

45 degrees south is well off the southern coast of Tasmania, placing all of Oz outside the useful range of the "Sun Compass". So the "Sun Compass" would have little utility in the southern hemisphere unless you are at the southern tip of S. America or New Zealand.

It's interesting how skewed our perspectives become in the northern hemisphere. 45 degrees north would be Halifax, Ottowa, Minneapolis, and Salem (Oregon).

Lee

Click to expand...

Yes, you are correct. Sorry. I was thinking of it by name and not by value.