Datasets:
configs:
- config_name: default
data_dir: mmu_jwst_primer_cosmos/dataset
tags:
- astronomy
license: cc-by-4.0
pretty_name: mmu_jwst_primer_cosmos
size_categories:
- 10K<n<100K
mmu_jwst_primer_cosmos HATS Catalog Collection
This is the collection of HATS catalogs representing mmu_jwst_primer_cosmos.
This dataset is part of the Multimodal Universe, a large-scale collection of multimodal astronomical data. For full details, see the paper: The Multimodal Universe: Enabling Large-Scale Machine Learning with 100TBs of Astronomical Scientific Data.
Access the catalog
We recommend the use of the LSDB Python framework to access HATS catalogs.
LSDB can be installed via pip install lsdb or conda install conda-forge::lsdb,
see more details in the docs.
The following code provides a minimal example of opening this catalog:
import lsdb
# Full sky coverage.
catalog = lsdb.open_catalog("https://huggingface.co/datasets/UniverseTBD/mmu_jwst_primer_cosmos")
# One-degree cone.
catalog = lsdb.open_catalog(
"https://huggingface.co/datasets/UniverseTBD/mmu_jwst_primer_cosmos",
search_filter=lsdb.ConeSearch(ra=150.0, dec=2.0, radius_arcsec=3600.0),
)
Each catalog in this collection is represented as a separate Apache Parquet dataset and can be accessed with a variety of tools, including pandas, pyarrow, dask, Spark, DuckDB.
File structure
This catalog is represented by the following files and directories:
collection.properties— textual metadata file describing the HATS collection of catalogsmmu_jwst_primer_cosmos— main HATS catalog directorydataset/— Apache Parquet dataset directory for the main catalog- ... parquet metadata and data files in sub directories ...
hats.properties— textual metadata file describing the main HATS catalogpartition_info.csv— CSV file with a list of catalog HEALPix tiles (catalog partitions)skymap.fits— HEALPix skymap FITS file with row-counts per HEALPix tile of fixed order 10
mmu_jwst_primer_cosmos_10arcs/— default margin catalog to ensure data completeness in cross-matching, the margin threshold is 10.0 arcseconds- ... margin catalog files and directories ...
Catalog metadata
Metadata of the main HATS catalog, excluding margins and indexes:
| Number of rows | Number of columns | Number of partitions | Size on disk | HATS Builder |
|---|---|---|---|---|
| 51,058 | 11 | 15 | 15.1 GiB | hats-import v0.7.3, hats v0.7.3 |
Catalog columns
The main HATS catalog contains the following columns:
| Name | _healpix_29 |
image.band |
image.flux |
image.ivar |
image.mask |
image.psf_fwhm |
image.scale |
mag_auto |
flux_radius |
flux_auto |
fluxerr_auto |
cxx_image |
cyy_image |
cxy_image |
object_id |
ra |
dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Data Type | int64 | list[string] | list[list<element: list<element: float>>] | list[list<element: list<element: float>>] | list[list<element: list<element: bool>>] | list[float] | list[float] | float | float | float | float | float | float | float | string | double | double |
| Nested? | — | image | image | image | image | image | image | — | — | — | — | — | — | — | — | — | — |
| Value count | 51,058 | 357,406 | N/A | N/A | N/A | 357,406 | 357,406 | 51,058 | 51,058 | 51,058 | 51,058 | 51,058 | 51,058 | 51,058 | 51,058 | 51,058 | 51,058 |
| Example row | 1918117816734487009 | [f090w, f115w, f150w, f200w, f277w, … (7 total)] | [[[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, … (96 total)], … (96 total)], … | [[[0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, … (96 total)], … (96 total)], … | [[[False, False, False, False, False, … (96 total)], … (96 total)], …… | [0.033, 0.04, 0.05, 0.066, 0.092, … (7 total)] | [0.04, 0.04, 0.04, 0.04, 0.04, 0.04, … (7 total)] | 26.48 | 2.555 | 0.07643 | 0.003804 | 0.2659 | 0.3691 | 0.1555 | 4779921206430939062 | 150 | 2.158 |
| Minimum value | 1918035224610977248 | f090w | N/A | N/A | N/A | 0.032999999821186066 | 0.03999999910593033 | 15.154260635375977 | 1.093169927597046 | 0.04745382070541382 | 0.0009272033930756152 | 5.68464383832179e-06 | 1.775023883965332e-05 | -1.4645973443984985 | -1793941820439658733 | 150.0225356463053 | 2.142978850173105 |
| Maximum value | 1918143149034739361 | f444w | N/A | N/A | N/A | 0.14499999582767487 | 0.03999999910593033 | 26.99997901916504 | 558.0476684570312 | 3149.892578125 | 46.66569519042969 | 2.4375405311584473 | 1.9571294784545898 | 1.3657711744308472 | 4779921206430994078 | 150.22745237191987 | 2.506566292130767 |
"Nested" indicates whether the column is stored as a nested field inside another "struct" column.
"Value count" may be different from the total number of rows for nested columns: each nested element is counted as a single value.
Crossmatch with another catalog
HATS catalogs can be efficiently crossmatched using LSDB, which leverages the HEALPix partitioning to avoid loading the full datasets into memory:
import lsdb
mmu_jwst_primer_cosmos = lsdb.open_catalog("https://huggingface.co/datasets/UniverseTBD/mmu_jwst_primer_cosmos")
other = lsdb.open_catalog("https://huggingface.co/datasets/<org>/<other_catalog>")
crossmatched = mmu_jwst_primer_cosmos.crossmatch(other, radius_arcsec=1.0)
print(crossmatched)
See the LSDB documentation for more details on crossmatching and other operations.
Dataset-specific context
Original survey
This dataset is based on the James Webb Space Telescope (JWST) NIRCam observations from early deep field surveys.
Data modality
The dataset consists of fixed-size image cutouts (96×96 pixels) centered on sources from photometric catalogs. The images are multi-band, with 6 or 7 filters covering wavelengths from approximately 0.9μm to 4.4μm.
Typical use cases
Images from these JWST deep field surveys have been used in a large number of scientific publications, including machine learning applications.
Caveats
Different surveys have different wavelength coverage, and missing bands are represented as arrays of zeros to simplify data loading.
Citation
The data are in the public domain. The dataset uses data products retrieved from the Dawn JWST Archive (DJA), an initiative of the Cosmic Dawn Center (DAWN).