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Sky Safari misreporting positive altitude as “below horizon”!

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#1 Roger Corbett

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Posted 09 June 2021 - 08:31 AM

Note:  Even though I solved this, I decided to post it, anyway, in case someone else stumbles upon this mystery!

 

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Was just checking the altitude of tomorrow's partial solar eclipse.  Discovered that, even though, the Moon and the Sun are above the horizon, and Info shows that their altitudes are positive, Sky Safari reports them as being “below horizon”!

 

The same is true of other objects near the horizon.  This “bug” goes all the way back to Sky Safari 4!

 

I tried this with planets, stars, and DSOs near the horizon at different times and days and looking in different directions.  It seems that anything above the horizon, but below 7 degrees, is reported as “below horizon”.  If the object is +7 or better, then SS switches to “above horizon”.

 

I also changed my location to different places in the U.S.  Same misdescription as “below horizon”!

 

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Postscript.  Just solved this.  Turned out that, for some reason, I must have changed a setting under Horizon and Sky— Horizon Altitude — to 7 degrees.  Perhaps, ages ago, I did that relative to satellite alerts or Jupiter moon transit-shadow events…unsure if that even makes sense or works.  Unfortunately, this means I’m going to have to go through EVERY one of my settings files to check them, and change that setting as needed!  Unlike SS 4, where one can save over an old setting file, this will mean typing in a new name, deleting the old file, and reordering the list as needed.  Nah!  I'll just ignore the contradiction.  No biggie, as I rarely observe anything that close to the horizon, anyway.

 

The nifty green horizon line that shows up when setting the value doesn't appear in the general Sky view if you have a Panoramic Image selected, so I never noticed this before.  Maybe it should appear whenever the Horizon Altitude is set above 0 degrees as a reminder.   In any case, I wonder whether the label “below horizon” is appropriate when the altitude is positive or whether it should be changed to “Below YOUR SET horizon” or some such to remove confusion.  


Edited by Roger Corbett, 09 June 2021 - 08:34 AM.


#2 btschumy

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Posted 09 June 2021 - 11:23 AM

This doesn’t sound right.  Could you check in the Horizon & Sky settings and make sure you horizon altitude is not set to 7 degrees?



#3 gmiller123456

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Posted 09 June 2021 - 03:57 PM

Related to this: but not really related, but still related.

 

Some applications, notably things like satellite predictions, won't report a hit unless an object is at least 10deg above the horizon.  This allows them to use a larger "step size" when computing the positions at different times.



#4 Roger Corbett

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Posted 17 June 2021 - 05:10 PM

This doesn’t sound right.  Could you check in the Horizon & Sky settings and make sure you horizon altitude is not set to 7 degrees?

As I noted at the start of my post, and in the original postscript, I had figured it out before posting,  I thought it would be useful to post it, anyway, in case someone else encountered the same confusing, frustrating, head-scratching message!

 

I think this may have happened because I one time fiddled with setting a tree-line faux horizon… and must have saved the settings after that as my default.  Alas, that spilled over into any other settings I later saved for various simulations, conjunctions, and comet appearances.

 

In any case, it'd good if the altitude statement were tweaked to reflect that changed pseudo-horizon.  It shouldn't report that an object is “Below horizon” when it's not.  It's below the “user-designated line”, not the actual horizon!


Edited by Roger Corbett, 17 June 2021 - 05:12 PM.



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