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How to figure out when your AOR can be observed.
The quick method
- Start up Spot. Load your AORs or create a target list including
the target in question. For this example, we choose the star "T Tauri"
as observed with IRAC.
- Obtain the visibilities of your target as follows.
From the target window (or any of several other places), click on
"visibility/orientation". (see also "important notes" at end)
The target window.
The visibilities for T Tauri.
- Note when the windows are for your observing cycle. For Cycle-4,
T Tauri is visible to Spitzer 2007 Sep 19 through 2007 Oct 28, and
2008 Feb 29 through 2008 Apr 07.
- Check the Baseline
Instrument Campaign (BIC). During the first window when T Tauri is
visible to Spitzer, IRAC is on 2007 Oct 15-21. During the second window,
IRAC is on 2008 Mar 4-11.
While the BIC is not cast in stone and may
be changed at any time (in fact it has probably changed since this
example was written), these dates are likely to be very close to the
actual dates during which this AOR may be scheduled.
- We schedule starting about 5 weeks out (see How Scheduling Works),
and schedules are finalized about 3-4 weeks out. Watch the schedules to see what is posted. (If
you're the PI or TC of the program, you will get email when the schedule
including your AOR is approved.)
Additional Important Notes
- You can calculate visibility windows for everything using the
'Calculate Visibility Windows for All' option under the Targets pull-down menu.
You can write this out to a file using the 'Save Target Visibility Windows' option from
the File menu.
- The target visibility windows do not
take into account
the effects of the slews within your AOR. For a more accurate
visibility window for a particular AOR, open the AOR dialog and
select the 'Vis Window' button at the bottom of the dialog.
This will calculate the visibility window taking into account all
positions observed in the AOR. This is particularly important
for large maps or IRS AORs that include a peak-up target. These
can create changes in the visibility window of days to up to a week
with respect to that calculated just for your original target position.
- If, for example, this Cycle-4 observation is not scheduled during the
first visibility window, then it is extremely likely that it will be
scheduled during the second window. If something happens and for whatever
reasons it does NOT get observed during the second window, it is likely
that the observation will be executed during the next available window,
e.g., during what is technically Cycle-5, depending on its scheduling
priority. For Cycle-5, an AOR will likely only get scheduled if its
priority is either 1 or 2, due to the indeterminate length of the Cycle.
Priority 3 AORs may not be observed at all during Cycle-5.
- If your target is in the continuous viewing zone (CVZ), it may be
scheduled at any time your instrument is on during the Cycle.
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