See this Comm Center thread from Dave Cambell. Essentially his ACP horizon dips down toward the South. Plans are getting failed for "never above" when the object is in the East. As they move to the South, the horizon against which their transit altitude is tested gets lower and they may actually peek above it on that night.



Probably the "never" test should be against the hard limit on Telescope (Min Altitude). If the calculation returns "never above" just defer the plan and let it be tested later against the possibly lower horizon.

 

  
SVN Comment
 
 

  
Author
  
rbdenny
 
 

  
Repository
  
svn+ssh://rbdenny@a2_svn_dc3/home/rbdenny/svn/astro/scheduler
 
 

  
SVN Revision
  
245
 
 

  
Affected files
  
/trunk/Help/RelNotes.htm (Modified)
/trunk/Scheduler/ACPSequencer.cs (Modified)
/trunk/Scheduler/Engine.cs (Modified)

 
 

  
Check-in comment
  
"Never above horizon" for the observatory's visible horizon is not a veto for 20 minutes. It is possible that the target will peek above the horizon at a later azimuth.
GEM:775

 

This is tricky, if a plan with multiple observations is running, and a second or later observation would hit any horizon when started, that's it. It has failed.

This test is right in the Engine in ApplySequencerLimits(), and that calls the ACPSequencer.CheckLimits. At present CheckLimits returns a hard limit only for tilt-up. It should also differentiate between the obs horizon and the telescope minimum altitude, returning a hard limit for that. Then for the Horizon limit we would just defer the observation for an hour or something, allowing it to maybe peek above the observatory horizon in ACP.