Tool

Photo checker

Line your photo up with the land, then see whether each light sits where an ordinary source can appear: a car on US-67 or another road, a train, a lit tower, a town, a star or a planet. It works only for photos taken from the Marfa Lights Viewing Area. Everything runs on your device.

1The photo

2Line it up

Three ways, best first if you can: Skyline uses the mountain outline, Lights uses tower lights and stars, and Both uses all of them. Or do it by hand: drag the model with Move model until the mountains roughly match, then press Refine; or tap a tower light or star with Match a point (two points fix the tilt too). If two photos from the same spot disagree, trust the one whose skyline lines up by eye.

3The lights

ExplainedNot explained by the catalogueCan't tell

    "Explained" means a known, ordinary source can appear at that spot, not that it certainly did. "Not explained by the catalogue" is not the same as unexplained: ranch lights, private roads, aircraft and satellites are not in the catalogue. Those are the lights worth a careful report.

    Report a sighting

    4What's drawn

    How it works: the photo is treated as a pinhole camera pointed from the platform (30.2751° N, 103.8828° W, eye 1.6 m). The skyline, roads, towers and the known-source mask come from the line-of-sight model (USGS lidar, normal refraction k = 0.13, and a strong-inversion envelope for the mask). Stars and planets come from Astronomy Engine. Lens distortion is not modelled, so wide-angle photos are less certain near the edges. Image decoding: exifr, UTIF.js and pako (MIT), libheif (LGPL-3.0, loaded only for HEIC files your browser can't open). How we tested this.