Data · dataset · 2025
2MASS Combined Calibration Field Source Table
Listed in NASA Data Portal
Photometric calibration for 2MASS was performed using observations of calibration fields made at regular intervals during each night of survey operations.
Description
Measurements of standard stars in the fields were used to derive the photometric zero point offsets as a function of time during each night. Atmospheric extinction coefficients were derived from 2MASS observations made over long periods.\n\n2MASS calibration fields, or tiles, are 1° long in declination and approximately 8.5' wide in right ascension.
There are 35 regular survey calibration fields distributed at approximately two hour intervals in right ascension near declinations of approximately -30°, 0° and +30°. An additional five calibration fields were defined in and around the Large and Small Magellanic Clouds to support the deep observation (6x) campaign towards the end of survey operations.\n\nOver the course of the survey, the regular calibration fields were scanned between 562 and 3692 times in nominally photometric conditions.
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Equatorial fields were observed from both observatories, so were observed more frequently than those near ±30° which were observed with only one telescope. The special Magellanic Cloud calibration fields were observed 108 to 468 times between November 2000 and February 2001.\n\nThe Combined Calibration Field Source Table contains the positions, aperture photometry, uncertainties, quality flags and cross-references to entries in the All-Sky Point and Extended Source Catalogs.\n\nA source was required to be detected on both the combined north-going and south-going images to be included in the extracted source database for a field.
The positions and photometry provided are the average values measured on the north- and south-going combined images.
Links
Get the data
- Resource irsa.ipac.caltech.edu/data/2MASS/docs/releases/allsky/doc/seca4_1.html ↗
download · from data nasa gov
- Resource irsa.ipac.caltech.edu/SCS?table=deepcal_src ↗
download · from data nasa gov
Where it is published
- NASA Data Portal dataset page data.nasa.gov/dataset/2mass-combined-calibration-field-source-table ↗
landing page · from data nasa gov
Catalogue records · 1
- CKAN API data.nasa.gov/api/3/action/package_show?id=28b03c77-df13-49cb-868e-b79f3e816… ↗
metadata API · from data nasa gov
Topics
Provenance · 1 source records, 8 field assertions
| Source | Key | Last seen | Raw |
|---|---|---|---|
| NASA Data Portal | 28b03c77-df13-49cb-868e-b79f3e816a3d | 10 d ago | JSON v1 |
| Field | Assertion | Extractor | Evidence |
|---|---|---|---|
| concepts[modality].local:modality:image | enrichment · data nasa gov | keyword-concept-rules@1.0.0 | title+description (65%) |
| concepts[modality].local:modality:tabular | enrichment · data nasa gov | keyword-concept-rules@1.0.0 | title+description (65%) |
| created_date | source · data nasa gov | connector:data_nasa_gov@1.0.0 | |
| description | source · data nasa gov | connector:data_nasa_gov@1.0.0 | /notes |
| license_text | source · data nasa gov | connector:data_nasa_gov@1.0.0 | |
| publication_date | source · data nasa gov | connector:data_nasa_gov@1.0.0 | |
| title | source · data nasa gov | connector:data_nasa_gov@1.0.0 | /title |
| updated_date | source · data nasa gov | connector:data_nasa_gov@1.0.0 |