Methodology and data sources

The rule that decides everything

IGW reads public data directly where a source permits it. Other sources are collected on a schedule and delivered as snapshots. A fresh retrieval does not guarantee that the source itself is current; check the timestamps and status shown with each section.

IGW checks shared mission and notice sources on a thirty-minute schedule. Reference datasets may be reused between checks to respect provider limits. Each section keeps the time of its last successful source retrieval. Data updates are published separately from site design changes.

The sources

The Space Devs, Launch Library 2

Read in the browser on every page load, and on a server every 30 minutes

Launches, vehicles, spacecraft, launch sites, agencies, stations, expeditions, spacewalks, dockings, landings, programmes and events come from Launch Library 2. The launch schedule is requested when the page loads. Mission snapshots are refreshed on a thirty-minute schedule. Launch plans can change between updates.

Countdowns are gated on precision. A launch the source knows only to the month is shown to the month, with the note that no countdown is possible at that precision, rather than being given a clock IGW invented.

FAA temporary flight restrictions

Read on a server every 30 minutes

The FAA's list of temporary flight restrictions, and then each notice's own detail record. It is read on a server because the FAA sends no cross-origin header, so a page script cannot read it at all.

IGW includes a restriction when its official text identifies launch or space operations. Boundaries come from the notice’s published geometry; proximity to a launch site alone does not establish a connection.

Altitude limits retain the notice’s stated reference: above ground level, above mean sea level or flight level. An unlimited ceiling is shown as unlimited. Unrecognised units remain as published.

NGA maritime warnings

Read on a server every 30 minutes

Broadcast warnings published by the National Geospatial-Intelligence Agency, read on a server for the same reason as the FAA. Zero marine notices is a real answer on a day when no active warning mentions launch operations, and the page says so rather than leaving a blank where a reader would assume a failure.

CelesTrak general perturbations element sets

Read in the browser on every page load

Public orbital element sets for the objects drawn on the globe. What you see is a propagated estimate, not live telemetry. An element set describes an orbit at a moment already past; the site advances it with SGP4, the standard model those element sets are built for, to work out where an object should be now.

IGW has no live telemetry feed for these objects. Tracks on the globe are calculated from published orbital elements. Objects without a usable position remain unplaced.

City of Starbase, Texas

Read on a server every 30 minutes

IGW reads beach access notices, road-delay windows and Mayor’s Orders from the City of Starbase’s public page. A listed window describes the city’s notice; it does not by itself confirm conditions on the road or beach.

The city’s wording is retained alongside any interpreted schedule. IGW interprets local times in America/Chicago and labels derived dates separately. Ambiguous dates or conflicting notices remain unresolved. An order without a published document is shown without a document link.

The launch-notices map

Built on a server every 30 minutes from the three sources above

The launch-notices page combines the three sources above into one snapshot every thirty minutes and adds three derivations of IGW's own. A restriction is classed as standing when its published window is thirty days or longer, or when its text invokes national-defence airspace under 14 CFR 99.7; standing restrictions are drawn faint and listed last, because they do not point to a particular launch or test, and the page says why beside each one. A notice is flagged new for forty-eight hours after IGW's reader first sees it; that first-seen time is IGW's record, not the issuer's, and notices that were already published when the tracking began are not flagged. Each notice is grouped under the launch facility whose own radius contains it; a notice outside every radius is listed by its region.

Marine warning areas are drawn from the coordinates in the NGA's own text where the text gives them; a warning that names a distance from a point is drawn as that circle. A warning whose text gives no coordinates but names a launch site is placed at that site as a named place, and one that names neither is listed without a shape. A Starbase closure has no published boundary. When the city names two places on State Highway 4 that IGW's road data holds, for example Production to Beach, the map draws the stretch of the road between them, along the road as OpenStreetMap maps it. When it names a place that data does not hold, such as Masseys, the end that resolves is placed as a point and the note says why. When an order names the highway without a stretch, the road is drawn faint from Starbase village to the beach as the road named, not as the closure's extent, which the city does not publish. The road line is read from the same tiles the map draws. Every shape on the map is a copy of what the issuer published or, where the note says so, the road the issuer names; the notice as issued is one tap away, and nothing on the page is for navigation, flight planning or operational use. The calendar and RSS feeds carry event notices only, with the same fields and the same limits, and are rebuilt when the notice set changes.

Spaceflight News API

Read in the browser on every page load

Headlines and summaries from publishers across the industry. Each item carries the name of the publisher that wrote it and the time it was published. IGW did not write them and does not edit them.

NASA image archive

Read in the browser on every page load

Archive imagery is supplied through NASA’s public image collection. Each item retains its published credit. Some items belong to third parties; a NASA listing or credit line does not establish permission to reuse it.

IGW's own YouTube channel

Read on a server every 30 minutes

The fifteen most recent IGW uploads, read from the channel's public feed. View counts are dropped once the snapshot is more than 24 hours old rather than shown as though they were current.

What the timestamps mean

• Read at, or read a number of minutes ago, is when IGW last successfully fetched the source. It is not when the source last changed.

• Published, issued or effective is the source's own time for the thing being described, at the source's own precision. IGW never adds precision the source did not publish.

• Not published means the source does not carry that field at all. It is not a zero, and it does not mean IGW failed to read it.

• Stale means a section’s last successful source check is older than its allowed refresh interval. That interval varies by source. Read the timestamp alongside any schedule or status.

• Unavailable means IGW could not retrieve usable data. An empty result from a successful check is different: the source may have no matching records. A retained snapshot keeps its original retrieval time.

When a source fails

Each ingest leaves its previous snapshot untouched when it fails, and the feed ingests run independently of one another so a single bad upstream day cannot take the others down with it. If a source redesigns the page IGW reads, the ingest reports that the structure changed and exits without writing, rather than replacing good data with an empty result.

Sections without usable data remain empty.

When it goes wrong

It has, and the corrections log says so in detail: an altitude ceiling that was invented from a sentinel value, three notices that lost the datum telling a reader whether a ceiling was above the ground or above the sea, and a withdrawn restriction that was served as current for four and a half hours.