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Subject:Feature Request: Sunrise / Sunset 

NigelF

8:35
Friday
26-Feb-2010

Location:
Aylesbury

Phone Model:
BB Curve 9630

Hi Stephen,

It would be useful when hiking (especially abroad) to be able to see the sunrise/sunset time for your current location. I know that you display the sun's position, but having the time displayed would help. Any thoughts ?

kind regards

Nigel.
 

Stephen

9:42
Friday
26-Feb-2010

Location:
Surrey, UK

Phone Model:
BB 9800 Torch
BlackBerry 8900
SE W910i
Nokia 5800

Hi Nigel,

Actually this is already available - its hidden in the Current Location/View Coordinates menu (scroll down to the end of the coordinate readings) and also in the context menu for Waypoints and the Plan/Map views to get the solar info for other locations. The latest version also gives the Transit Time and Altitude (the time close to midday when the sun is highest in the sky) - pretty useless info, but occasionally fascinating!

(By the way, if you're abroad don't forgot to alter the phone timezone so that the 'Local Time' readings are displayed correctly)

Cheers,
Stephen

ps: today's readings for London, from TMJ:
Sunrise 102° ESE at 6:50 (6:50 UTC)
Transit 30° (Alt) at 12:13 (12:13 UTC)
Sunset 257° WSW at 17:35 (17:35 UTC)
Day Length: 10:44.26
 

NigelF

19:35
Friday
26-Feb-2010

Location:
Aylesbury

Phone Model:
BB Curve 9630

Hi Stephen

Should have known ! Perfect - Thanks for the info.

Cheers

Nigel
 

yano

9:55
Monday
22-Mar-2010

Location:
Germany

Phone Model:
SE K610i

Stephen,

sorry for boring you again ... I swear that this time I have slept a night over before posting ... :)

How are the Solar Information calculated?!
Since yesterday (just a coincidence?) TMJmobile displays odd values for the current location as well as for all the waypoints of mine. Here the today (h10:45) values for my current location in Germany:

Date 22-Mar-2010
Azimuth 327° NNW
Altitude: -36° (Set)          <--- !!
Sunrise 152° SSE at 15:51 (14:51 UTC)  <--- !!
Transit 12° (Alt) at 17:10 (16:10 UTC)  <--- !!
Sunset 272° W at 18:29 (17:29 UTC)  <--- !!
Day Length: 2:38.15         <--- !!


Yesterday, sunRISE was at 18:00 (!) and sunSET at 06:00 (!) ...

Furthermore: the Sun Alt. in the Navigation page shows all the time 0°

It seems that the local time must be mad!

For your info: my phone Local Time is set all the time GMT+1, no daylight saving. I've re-set the local time, re-booted the phone, re-connected it via bluetooth to my GPS puck, to my laptop and to your web site ... no chance! :(

Any clue what is going wrong?!

Thanks again in advance ...

Cheers,
yano
 

Stephen

10:58
Monday
22-Mar-2010

Location:
Surrey, UK

Phone Model:
BB 9800 Torch
BlackBerry 8900
SE W910i
Nokia 5800

Hi Yano,

Yes it is definitely a strange bug this one!

I first noticed it exactly a year ago, but when it seemed to fix itself after a couple of days I put it to one side (ie forgot about it!). Then it popped up again towards the end of October, and again now, around March 21st so I think it must be related to the Spring and Autumn Equinoxes. This is the time when the Polar axis effectively 'flips' between pointing towards or away from the sun, so I suspect this might be introducing a 'division-by-zero' or similar rounding error into the sun calculation formula.

My problem is that the formulas are very complex - I don't fully understand the maths behind it (I simply transcribed the written formulas into Java code!), so I'm not sure that I'm able to fix it very easily. Having said that I should probably at least get TMJ to display a message around this time to explain the inaccuracy.

Bear with it - it should clear itself within a day or two!

Cheers,
Stephen
 

macpanda

23:06
Monday
22-Mar-2010

Location:
Nailsea, North Somerset, UK

Phone Model:
Nokia N95
Sony Ericsson C905

Hi Stephen

I noticed this too yesterday (TMJ spent all day in Night colours). I wouldn't bother to comment after reading the rest of the thread, but thought it would be worth pointing out that I had exactly the same values yesterday (18:00, 06:00) for waypoints in SW england as Yano had for Germany. May help shed some light if you do attempt to fix it.

Paul
 

Stephen

10:45
Tuesday
23-Mar-2010

Location:
Surrey, UK

Phone Model:
BB 9800 Torch
BlackBerry 8900
SE W910i
Nokia 5800

Hi Paul,

Righto, thanks for that. Just had a look at TMJ this morning and it seems to be back to normal again here - the sunrise/sunset times more or less correllate with other website-based calculators for the few random coordinates that I tested. Will try and work through the maths code sometime before September 22nd-ish (though may give up and just add the warning message instead)!!

Cheers,
Stephen
 
 

yano

11:00
Tuesday
23-Mar-2010

Location:
Germany

Phone Model:
SE K610i

Stephen,

as you predicted, the values are back to normal again here too: we definitely sprang into spring :)

As far as I am concerned, now the bug is known and it doesn't worth to dive into the math formulas for just 2+2 days a year ...

Thanks&Cheers,
yano

 

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