FITS BINTABLE — Typed Columns with TUNIT (.fits)
A FITS binary table with four typed columns, big-endian numerics packed with no inter-field padding and TUNIT declaring milli-jansky on the two flux columns. It is the fixture for a table reader that has to build a row struct from TFORM codes rather than guess widths.
| Column | TFORM | TUNIT | Type |
|---|---|---|---|
| SRC_ID | 1J | - | 32-bit big-endian integer |
| FLUX | 1E | mJy | 32-bit big-endian float |
| FLUX_ERR | 1E | mJy | 32-bit big-endian float |
| BAND | 8A | - | 8-byte space-padded ASCII |
Specifications
- Extension
- BINTABLE
- Rows
- 12
- Fields
- 4
- Row Bytes
- 20
- Tform
- 1J, 1E, 1E, 8A
- Tunit
- mJy on FLUX and FLUX_ERR
- Byte Order
- big-endian
- Seed
- 20260814
Testing contract
Expected to pass- Scenario
- Read the BINTABLE extension and reconstruct all four columns using the TFORM codes and NAXIS1 row width.
- Expected result
- You get 12 rows of 20 bytes, SRC_ID counts 1..12, FLUX_ERR is five percent of FLUX to within float32 precision, and BAND cycles g/r/i as 8-byte space-padded strings.
What is a .fits file?
FITS (.fits, Flexible Image Transport System) is the standard binary format in astronomy. It pairs human-readable 80-character header cards (in 2880-byte blocks) with binary image or table data, storing pixel arrays, coordinates, and instrument metadata. It has been the astronomical archive format for decades.
How to use this file
Use an example .fits file to test FITS readers (astropy, CFITSIO, DS9), header-card parsing, and image or table extraction, or to verify block-alignment handling.
How to use this file for testing
“FITS BINTABLE — Typed Columns with TUNIT (.fits)” is a deterministic Novus Examples fixture for Scientific data, Serialization testing, Data import. Citation catalogs (BibTeX, RIS), chemistry structures (MDL Molfile, PDB), and gridded binary data (NetCDF, FITS) — for testing reference managers, molecule viewers, and scientific-data loaders.
Documented properties for this file: seed 20260814 · 12 rows · 4 fields. Compare results against paired or grouped companions on this page when present (clean↔damaged, searchable↔scanned, or format twins) so scores stay reproducible across runs.
Download the file once, keep the path stable in CI or local scripts, and treat the spec table as the contract: dimensions, seeds, field lists, and roles are intentional. Corrupt or invalid samples are labelled as such — expect parsers to fail loudly rather than silently accept them.
Scientific fixtures are small, valid, and fully synthetic — no real organism, patient, sample, or observation. Point your parser or loader at the file and check it reads the documented records, variables, or headers; binary formats ship a readable twin or metadata listing for comparison.
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