Aquarius Ancillary L-Band Celestial Sky Brightness Temperature Maps

Three maps provide L-band (21 cm wavelength) brightness temperature of the celestial sky, used to process NASA Aquarius instrument data. The dataset contains 1,039,681 grid points (721 declinations by 1441 right ascensions) at 0.25-degree intervals in the J2000 ECI reference frame. Created by POCLOUD for NASA, the maps model the galactic microwave continuum and atomic hydrogen line emissions, with variations in handling the Cassiopeia A radio source.

Use Cases

• Calibrating satellite radiometer data by subtracting modeled celestial sky background emissions.
• Comparing three different methods for incorporating a strong point source (Cassiopeia A) into a diffuse sky map.
• Analyzing the spatial distribution of L-band galactic microwave continuum emissions across declination and right ascension coordinates.
• Studying the contribution of atomic hydrogen line (HI) emissions to the total sky brightness temperature at 21 cm.

Strengths

• Provides a high-resolution celestial grid with 1,039,681 data points sampled at 0.25-degree intervals.
• Includes three specific model variants for handling the Cassiopeia A radio source, allowing for methodological comparison.
• Explicitly includes both microwave continuum and atomic hydrogen line (HI) emissions in its model.

Limitations

• Key metadata conflicts exist: the license is listed as both 'unknown' and 'other-license-specified', and the last update date differs by over a decade between platforms.
• The brightness temperatures are modeled as temporally invariant and neglect polarization, which may not reflect real-time or polarized observations.
• Column names and exact dataset size (rows, file size) are not provided by any source.

Provenance

Source

POCLOUD for NASA Aquarius mission.

Collection Method

Modeled sky brightness temperatures gridded on the Earth Centered Inertial (ECI) reference frame epoch J2000.

Time Range

Assumed temporally invariant; no specific observation time range provided.

Freshness

2026-03-13 17:33:31.374906

Geography

Celestial sphere coverage: full sky from -90 to +90 degrees declination and 0 to 360 degrees right ascension.