The dashed line shows the nominal aperture position angle for the selected instrument as a function of date.
The green band shows the full range of aperture position angles available through telescope roll.
Gaps indicate dates when the target is not observable by JWST.
The downloadable CSV provides the underlying visibility calculation, including:
Minimum V3 PA, Maximum V3 PA, Minimum Aperture PA, Maximum Aperture PA, Nominal Aperture PA, Gregorian Calendar Date, and Modified Julian Date.
{{ vis_plot | safe }}
{% if contam_plot %}
{% if pa_val == -1 %}
Target Contamination for all Position Angles at Epoch={{ epoch }}
{% else %}
Target Contamination for PA={{ pa_val }} at Epoch={{ epoch }}
{% endif %}
{% if pa_val == -1 %}
The upper panel shows contamination across the reported spectral channels at the V3 position angle selected with the slider.
The lower curve shows the mean contamination across those channels at each V3 position angle. Shaded intervals identify angles where at least one channel exceeds the stated contamination threshold.
Contamination is reported as the contaminant fraction, C/(T+C), evaluated from the target extraction region.
Both axes are displayed from 0% to 10% to make low contamination easier to assess. Values above 10% are retained but clipped by the displayed range.
Grey regions mark V3 position angles at which the target is not observable during the selected epoch.
{% else %}
The top plot shows the simulated observation at the given position angle.
The circles show the detector location of the 0th order, which you can click to resolve in Vizier.
Red lines show the predicted order 1, 2, and 3 trace positions for the target (solid) as well as all contaminant sources (dashed).
If a source's Teff value is listed as "---" on hover, a temperature could not be determined and a 2300K model SED will be used for contamination estimation.
Pink dashed lines show the predicted order 1, 2, and 3 trace positions for contaminant extended sources.
The bottom plot shows the fractional contamination of orders 1 (blue), 2 (red), and 3 (green) in each detector column.