Somewhere in the asteroid belt there is a rock called London, another called Brighton and one called Midsomer Norton. I mapped 2,193 asteroids (2,206 namings) named after places on Earth, each with a line to the observatory that found it, to see which towns have one, who named them, and from how far away.
When you discover an asteroid you get to suggest its name. Most discoverers honour people: colleagues, family, scientists, musicians. But about one asteroid in five with a recorded namesake honours a place, and that is where this map comes in. Towns and villages, rivers and mountains, provinces and countries, universities and observatories all have their rock in the sky, chosen by an astronomer somewhere else on Earth, and approved by the International Astronomical Union.
Wikidata, the open database behind Wikipedia, records what 11,268 asteroids are named after. 2,206 of those namings are of places with coordinates, 19% of the total; 65% are of people and the rest of other things, from gods and novels to bands and locomotives. For each place I know which observatory found the asteroid, so I can draw the line between them: the naming geography of the solar system.
Each dot is a place, coloured by what kind of place it is. Black stars are the observatories that found the asteroids; click one to see every place it named, or click a place to see its asteroid and the line back to where it was found.
Places from Wikidata's "named after" statements for asteroids, at the coordinates Wikidata gives the place (a region or river is a single point). Lines join each place to the discovery site of its asteroid, along the great circle. Mythical and fictional places are left out. Earth: the Inked World map style on OpenStreetMap data via OpenFreeMap.
Of the 11,418 namings, 7,463 (65%) are of people, 2,206 (19%) of places with coordinates and 1,749 (15%) of other things. Among the places, towns, cities and villages lead with 1,150 (52%), then observatories, universities and other institutions (309), mountains, islands and other natural features (280), regions (191), rivers and lakes (140) and countries (82).
What the places are
Place namings by kind. Hover a block.
By modern country, Japan has 421 place namings (19%), far ahead of Germany (153), Russia (137), Italy (135) and the United States (130). Per head the leaders are smaller countries with busy asteroid hunters: Finland (11.8 per million people), the Czech Republic (9.8) and Sweden (8.1). Places in 111 countries have an asteroid in all.
Countries with the most places in the sky
Left: place namings by modern country. Right: per million people, for countries of at least a million with five or more. Hover a bar.
The 237 observatories behind these namings are led by La Silla in Chile (224 places), the Crimean Astrophysical Observatory (164) and Palomar in California (99). But a big telescope does not name its neighbours. Only 4% of La Silla's places are in Chile: the names follow the astronomers, not the telescope. The Belgian Eric Elst, the most prolific namer of places here with 167, worked at La Silla and named 36 places in France and 16 in Belgium; the Uppsala survey at La Silla named Swedish places. Purple Mountain Observatory in China named Chinese places almost without exception (99%).
The observatories that named the most places
Place namings by discovery site; share in the observatory's own country; median distance to the place; share within 100 km. Click a row to see its lines on the map.
Half of all places lie within 508 km of the observatory that found their asteroid, and 27% within 100 km. The most local namers are small observatories run by devoted amateurs and their professional neighbours. Kleť Observatory, on the mountain of Kleť in South Bohemia, named 98 places, 81% of them Czech and 50% within 100 km. Japan's amateur observatories did the same for Japanese towns: 92% of the asteroids named after places in Japan were found in Japan, and 46% within 100 km of the place. For the Czech Republic it is 90% and 55%.
How far from the observatory
Distance from the discovery site to the named place, all place namings with both positions. Hover a column.
Big telescopes name the world. Small ones name the next valley.
82 asteroids are named after observatories and telescopes themselves, 26 of them after the very observatory that found them.
26 asteroids in Wikidata are named after places in the United Kingdom, 16 of them towns and cities. Almost all were found abroad, at observatories such as La Silla, Palomar and Siding Spring. The exceptions are home-grown: an amateur observatory at Church Stretton in Shropshire found the asteroids named Church Stretton and Salopia, the old name for Shropshire, and a small observatory at Stakenbridge found Old Joe, named after the clock tower of the University of Birmingham. Click a row to find the place.
Every British place with an asteroid in Wikidata
By minor planet number. Click a row.
Data. Everything comes from Wikidata (CC0), queried through QLever: every asteroid with a "named after" (P138) statement, with its number, discoverer, discovery site and date, and the namesake's type, coordinates and country. I removed the duplicate rows the query makes for each discoverer and type. A namesake that is not a person and has coordinates counts as a place, unless it is mythical or fictional or not a place at all (languages, species, ships, battles and other events, peoples, television programmes, and organisations with no site of their own); I checked the whole list by eye. Kinds of place come from keyword rules on the namesake's Wikidata types. Countries are modern: the country Wikidata records for the place, or Natural Earth's borders where Wikidata is silent, names several countries or names a historical state; Crimea is counted as part of Ukraine; per head uses Natural Earth's population estimates. Distances are great circle distances between the discovery site and the place's point.
Caveats. This covers only the named minor planets that Wikidata links to a namesake, not all named minor planets; how complete it is varies by country and era, and I have not compared it with the Minor Planet Center's full list of names. The discoverer usually proposes the name, but not always, so the observatory is the place of discovery rather than certainly the place of naming. A region, river or country is reduced to one point, so its distance is rough. Asteroid names are Wikidata's multilingual label, or the English label, or a label in another language.