Identify
Confirm the object in the IAU/USGS Gazetteer or the Earth Impact Database; fix a persistent ID, coordinates and duplicates.
CRATER.WORLD / EXPEDITIONS
Expeditions: from orbit to the crater rim
Two linked tracks: online expeditions that read public orbital and ground data, and field expeditions to confirmed impact structures on Earth. Both start with the same question — what does the evidence actually show?
Online expeditions DESIGNED
Anyone with a browser can follow an object from its official record to a reproducible conclusion. No telescope time is needed — public archives already hold the data.
Collect
Gather imagery, topography, radar and spectral data from public archives; record mission, instrument, date and licence.
Measure
Measure diameter, depth and morphology with a documented method and a stated uncertainty.
Reconstruct
Reconstruct only where the source is insufficient — and label it as a reconstruction.
Publish
Release a citable report with a source ledger, a version number and a correction history.
Public data we work with
- Moon — Lunar Reconnaissance Orbiter (LROC)
- Mars — Mars Reconnaissance Orbiter (HiRISE, CTX)
- Mercury — MESSENGER
- Venus — Magellan radar
- Outer worlds — Galileo, Cassini, Juno
- Earth — public satellite imagery, radar and elevation models
- Archives — NASA PDS, ESA PSA, USGS Astrogeology, Solar System Treks, JPL Horizons
Field expeditions IN PREPARATION
A field expedition verifies on the ground what the data suggests: structure, rim, ejecta, central uplift, samples and context. No field expedition has been conducted yet.
Regions under study
Candidates are chosen from confirmed structures in the Earth Impact Database. The Nordic–Baltic belt — for example Tvären, Siljan, Lockne, Dellen and Kaali — is the first region under study. Nothing is announced.
Team (proposed roles)
Expedition lead · field geologist · geophysicist · surveyor (GNSS and mapping) · safety officer and medic · visual-documentation lead · local liaison · educator.
Camp and equipment (categories)
Field camp (tents, cooking, water) · power and communications · GNSS and mapping · geological field kit · first aid and safety · documentation (photo, video, notebooks) · drones only where permits allow.
Rules before any visit
Written permission from landowners and the responsible national or regional authority · respect for protected areas, heritage and local communities · no sampling without a permit · a written safety plan and insurance · open return of the data.
No expedition is announced until the permit, the safety plan and the team are confirmed in writing.
Hybrid: satellite pre-survey, then on-site verification
The online track prepares the field track: remote data selects the site and the questions; the field team returns measurements that correct the remote record. Every correction is published.
First route: Nordic–Baltic impact structures IN PREPARATION
We are studying eight confirmed impact structures in Sweden and one in Estonia as the first region for online and field work. This is a plan, not an announcement.
Sweden
Siljan Ring · Dellen · Lockne · Målingen · Mien · Granby · Hummeln · Tvären
Estonia (Saaremaa)
Kaali
Stages
- Online reconnaissance of every structure: public databases, relief, geology and publications, with sources for every figure.
- The structure nearest to Stockholm, Tvären, as the first and simplest field check — a circular bay rather than a visible bowl.
- Central Sweden: Siljan Ring and Dellen.
- The north: the Lockne–Målingen pair.
- Extension to the Baltic: Kaali on Saaremaa.
Before any visit
- Written permission from landowners and the responsible authority.
- Respect for protected areas, heritage and local communities.
- No sampling without a permit.
- A written safety plan and insurance.
- A team confirmed in writing; open return of the data.
Figures for these structures (diameter, age, coordinates) are being verified against primary sources and are not published yet. No field expedition has been carried out and none is announced. No partners are announced; institutions are listed only after written confirmation.
Propose an object, a site or a method
Researchers, teachers and institutions can apply to take part. Write through the contact form or to contact@crater.world.