How to Search the Gale Crater Mineralogy and Geochemistry Database

To search the Gale Crater Mineralogy and Geochemistry (GCMG) database, start at the homepage and choose one of three SEARCH BY entry points: Drill or Scoop, Rover traverse, or CheMin Wheel. Each opens a different view of the same Curiosity sample dataset, so the right choice depends on whether you know a sample name, want to follow the rover's path, or want to browse mineralogy results by CheMin analysis. The homepage presents these as three labeled options, each with a "Click Here" link.

The three search paths and when to use them

Drill or Scoop

Use this when you already have a sample in mind — for example, a name you saw in a paper or a news update. The database's news items name samples directly, such as Altadena, Valle de la Luna, Marimba2, Quela, Sebina, Mammoth Lakes 2, and Kings Canyon, so this is the natural path for checking whether a named sample's data is present and current.

Rover traverse

Use this when your question is spatial: which samples were collected at which points along the route. The homepage frames the dataset around the mission's extent — 4,823 sols since landing in August 2015 and 22.58 miles driven from the landing site — and provides a "Where is Curiosity?" element, so the traverse view fits questions about sampling location and sequence rather than a single named sample.

CheMin Wheel

Use this when mineralogy is the starting point. CheMin is the rover's X-ray diffraction instrument, and the "CheMin Wheel" label indicates a view organized around those mineral composition results. This suits comparing mineral assemblages across samples rather than locating one sample.

Steps to open a search

1. Go to the GCMG homepage at galecrater.samples.odr.io.
2. Find the SEARCH BY section.
3. Select the path that matches your question: Drill or Scoop, Rover traverse, or CheMin Wheel.
4. Click the Click Here link under that heading.
5. Expected result: the corresponding search or browse view for that path opens, from which you can locate sample data.

If you are unsure which path to use, start with Drill or Scoop when you have a sample name; otherwise use Rover traverse for location-based questions or CheMin Wheel for mineralogy-based ones.

Check the news feed before you search

The homepage's NEWS section records dataset changes, which matters because a sample you are looking for may be new or recently revised. Recent entries include:

• 03/19/2026: data added for samples Altadena and Valle de la Luna.
• 03/03/2026: updated mineral composition tables incorporated for Marimba2, Quela, and Sebina.
• 04/17/2025: data added for Mammoth Lakes 2 and Kings Canyon.

If a search returns nothing for a sample you expected, check the news feed first — the sample may not yet be included, or its tables may have changed since a prior download.

Citing the database

If you use results in published work, the homepage provides the citation to use:

Lafuente, B., Blake, D., Bristow, T., Rampe, E., Downs, R., Sarrazin, P., Downs, G., Stone, N., Pires, A., Vaniman, D., Yen, A., Franz, H., Lyness, E., & Fraeman, A. (2021). Gale Crater Mineralogy and Geochemistry database (GCMG). [Data set]. Open Data Repository. https://doi.org/10.48484/JN48-YW52

Common sticking points

• No result for a known sample: confirm the spelling against the news entries, and check whether the sample was added after your last visit.
• Choosing the wrong view: the three paths lead to different presentations of the same underlying data; if one view does not show what you need, switch paths rather than assuming the data is missing.
• Assuming a fixed dataset: the news feed shows the database is actively updated, so record the date you accessed it alongside any results you rely on.