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For the complete documentation index, see llms.txt.
An AOI overflight event is a predicted visibility window during which a spacecraft is above an AOI’s elevation threshold as seen from at least one point inside the AOI — the first-to-see / last-to-lose semantic. The events surface lives at the bottom of the AOI Overview page; it visualises every event in a 7-day window on a timeline and lists every event below the timeline. Route: Visible on the Events band of the AOI Overview page once you select an AOI.

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Events Surface Layout

The events surface composes four elements:
ElementDescription
Spacecraft filterDropdown defaulting to All spacecraft. Selecting one spacecraft narrows both the timeline and the list to that vehicle.
Recompute buttonRefreshes the 7-day overflight schedule across every spacecraft in the workspace.
7-day timelinePer-spacecraft bars plotted across a now…now+7d axis. Bar position is the entry time, width is the pass duration, height scales with the peak elevation.
Column-less listEach event renders as a row with embedded labels (no table columns). Click a row to expand its full per-event detail.

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7-Day Timeline

The timeline anchors at the current instant and spans 7 days. A row of day-tick labels lines the top axis. For every spacecraft that produces an event in the window, one row plots its passes:
  • Bar position along the row marks the entry time.
  • Bar width marks the pass duration.
  • Bar height scales with the peak elevation — taller bars are higher passes.
The spacecraft filter applies to both the timeline rows and the list. Picking a specific spacecraft hides every other row on the timeline.

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Column-Less Event List

The list renders each pass as a single row with embedded labels — not a table. From left to right: the spacecraft name, a Peak elevation badge in degrees, a Duration badge, and the entry time formatted relative to now (e.g. in 2h 30m, in 1d 4h). A chevron at the right edge signals expansion. Clicking the row selects it for the per-event detail panel. Only one row is selected at a time — clicking another row swaps the selection; clicking the same row again deselects it. The detail panel renders beside the list on viewports wider than ~768 px (the two columns side-by-side fill the events band) and beneath the list on narrower viewports (the panel stacks under the selected row). When the spacecraft filter is set to a single vehicle, an N of M shown indicator appears between the timeline and the list so you always know how many events the filter is hiding.

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Per-Event Detail

Expanded event detail showing entry, peak, exit, peak elevation, peak point, azimuth, and sub-satellite point The expanded detail exposes every operator-facing field on the event:
FieldDescription
EntryThe earliest instant any point in the AOI sees the spacecraft above the elevation threshold (UTC).
PeakThe instant of the maximum elevation in the pass (UTC).
ExitThe latest instant any point in the AOI still sees the spacecraft above the threshold (UTC).
Peak elevationMaximum elevation angle in degrees observed during the event, taken from the AOI point that achieved the highest elevation at that instant.
Peak pointGeodetic latitude / longitude (WGS-84, °) of the AOI point that observed the peak elevation, rounded to two decimals.
Azimuth at peakAzimuth angle in degrees from the peak point to the spacecraft at the peak instant, measured clockwise from local north.
Sub-satelliteGeodetic latitude / longitude (WGS-84, °) of the ground point directly below the spacecraft at the peak instant.
Sub-intervalsCount of disjoint visibility windows when the AOI shape produced more than one for the same pass. Surfaced only when the count is greater than 1.
PiecesPer-piece peak point and peak elevation breakdown for multipolygon AOIs. Surfaced only when the AOI is a multipolygon.
Computed atThe instant the event was last refreshed (UTC).
Multipolygon AOIs that span very different latitudes can produce events whose Peak point sits on one piece of the geometry — the Pieces breakdown surfaces the per-piece peak point and peak elevation so you can confirm which part of the AOI saw the spacecraft. Non-convex AOIs that produce more than one disjoint visibility window during a single pass surface the Sub-intervals count so you can see how the pass split.

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Filtering by Spacecraft

The spacecraft filter is a single dropdown at the top of the events surface. Its options are:
OptionEffect
All spacecraftDefault. The timeline and list show every event from every contributing spacecraft.
<Spacecraft name>Only events from the selected vehicle are shown. The N of M shown indicator appears beneath the timeline so the filter weight is always visible.
The dropdown’s option list only includes spacecraft that contributed at least one event to the current forecast — vehicles that never produced an event for this AOI are silently excluded. The filter resets to All spacecraft whenever you switch between AOIs.

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The Recompute Action

Click Recompute to refresh the 7-day overflight schedule for the AOI across every spacecraft in the workspace. The button shows a spinner while the recompute runs; the timeline and the list keep the previously computed rows visible during the run. The Last computed label refreshes on success. The Recompute button is disabled when:
  • The AOI is Inactive (toggle it active again on the Overview page).
  • The AOI is Out-of-window (its validity window has not started yet or has already ended).
  • A recompute is already running.

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Auto-Trigger on Edit

Editing any of the following AOI fields triggers an automatic recompute when you commit the edit — you do not need to click Recompute afterwards:
  • Geometry edits (any vertex, disk centre or radius, multipolygon piece).
  • Elevation threshold changes (the Min elevation field).
  • Validity window changes (either bound, set or cleared).
  • Flipping the AOI active toggle in the identity hero (Active ↔ Inactive).
Identity fields — name, description, tags, colour — do not trigger a recompute. Existing events stay in the list after an identity-field-only edit.

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Timing Accuracy

Event timing accuracy is better than 1 second at day 1 of the forecast horizon. For spacecraft in LEO at altitudes below 500 km, the timing may drift up to a few seconds at day 7 because of atmospheric drag uncertainty. After a fresh orbit determination or a known manoeuvre, click Recompute again to anchor the schedule on the new ephemeris.

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Lifecycle Banners

When the AOI is in a state that explains why no events should be displayed, the events surface replaces the timeline and list with a banner. Only one banner is rendered at a time, and the cascade is:
BannerWhen it shows
Recompute failed — try againThe most recent recompute rejected. The error clears the next time you click Recompute.
AOI is outside its validity window. No events to display.The current time falls outside the AOI’s validity bounds.
AOI is inactive — no events to display.The AOI has been paused from the identity hero.
No overflights computed yet — click Recompute to generate the forecastThe AOI has never had a recompute run.
No overflights in the next 7 days — try lowering the elevation threshold or check spacecraft orbit dataThe recompute succeeded but produced no events for any spacecraft.
Spacecraft that have no orbital data are silently excluded from the forecast — only vehicles that actually contribute events appear in the spacecraft filter.
  • Areas of Interest overview — the page that hosts the events surface, plus the identity hero and geometry block.
  • AOI Map — the world map view, where each AOI’s hovercard surfaces its next overflight and a compact 7-day timeline.
  • Create an AOI — define an AOI and configure its lifecycle.
  • GeoJSON file format — accepted geometry types for AOIs created from a GeoJSON document.