Impact Watch

The problem

Two public records, neither one ready to map

NASA publishes the fireballs that United States government sensors detect, and Wikipedia keeps the list of confirmed impact structures that began as the Earth Impact Database. Both are public and both are worth mapping, but reading them right is where the time goes: the impact energy is an estimate calculated from light, every fireball value arrives as text with the coordinate signs in separate fields, and the crater ages are written as text.

Watch it work

Episode 15 — Impact Watch (6:33)

Two public sources end to end: where the fireball and crater records live, the three details that cost the most time, and the map, 3D tour and Moon view they turn into.

What it covers

Two sources, three details, one map

• The sources: the Fireball Data API of NASA’s Center for Near Earth Object Studies at the Jet Propulsion Laboratory gives each event a date, a position, an altitude, a speed and two energy values. The API does not answer requests from web pages on other sites, so Impact Watch ships a dated copy of 878 events read on July 12, 2026. The craters come from the English Wikipedia list of impact structures on Earth, read on September 28, 2026, under CC BY-SA 4.0, with missing coordinates filled from Wikidata.
• Detail one, the impact energy is calculated: the sensors record the light of the fireball as radiated energy, and NASA converts it into an estimated impact energy in kilotons with a published formula — between 5 and 16 times the radiated energy, and about 13 times for a typical event. For Chelyabinsk in 2013, 375 trillion joules of light become 441 kilotons. Impact Watch sizes every fireball by that calculated value, on a log scale.
• Detail two, every value arrives as text and the coordinates have no sign: each event is a list of nine strings, and latitude and longitude are positive numbers with north or south and east or west in separate fields. Impact Watch applies the sign before it places a point. On October 3, 2026 the live API listed 1,073 events, 186 of them without a location; in the July copy, 519 of the 878 events have no speed and 286 have no altitude.
• Detail three, the crater ages are text: of the 190 ages, 43 carry an uncertainty, 56 are ranges, 36 are upper limits and 12 are approximate. Impact Watch keeps the text as the list gives it and formats it for display in millions of years — Chicxulub reads 66.051 plus or minus 0.031 in the list and 66.1 on the map.
• How it becomes a map: craters are rust-orange circles sized by diameter and fireballs are cyan-white points sized by energy; chips count both layers and name the largest of each; Craters, Fireballs and Both switch the layers; two sliders set a minimum crater diameter and a minimum fireball energy, each with a live count; a timeline counts fireballs per year from 1988 to 2026; two top ten lists fly the map to the largest craters and the most energetic fireballs; and a 3D view puts the craters on real terrain, with a tour of ten of the largest and a Moon view of six well-known lunar craters.

What it does not do

• Not a live feed — the fireball file is a dated copy from July 12, 2026, and the live NASA API has added events since.
• Not a measurement of the rock — the impact energy is NASA’s estimate calculated from the light of the fireball.
• Not an official NASA or Wikipedia product — the records are theirs; the map and the app are All Things Spatial’s.

Where the data comes from

Every source in the episode

• NASA/JPL CNEOS Fireball Data API — ssd-api.jpl.nasa.gov/doc/fireball.html
• CNEOS fireball reports — cneos.jpl.nasa.gov/fireballs/
• Wikipedia, List of impact structures on Earth (CC BY-SA 4.0) — en.wikipedia.org/wiki/List_of_impact_structures_on_Earth
• Wikidata (CC0), coordinates for rows without them — wikidata.org
• Esri dark gray basemap, world elevation and imagery (3D) — esri.com
• Source sheet with every endpoint — allthingsspatial.io/pages/sources.html

The fireball records are the work of a United States agency and are in the public domain. The crater list is Wikipedia text under CC BY-SA 4.0, and the crater file in the app carries the same license. The credits sit in the Impact Watch footer: Wikipedia, Wikidata and NASA/JPL CNEOS, and Esri for the basemap.