uvex_transients.dust.dust_map#

uvex_transients.dust.dust_map() → PlanckGNILCQuery[source]#

Return the Planck GNILC E(B-V) sky map, downloading and caching it on first use.

The map is fetched via astropy.utils.data.download_file() (cached to disk, with the ESA mirror as a fallback source), and the resulting PlanckGNILCQuery is itself process-cached via functools.cache(), so repeated calls – even across millions of per-event reddening lookups – pay the download/load cost only once.

Returns:

Queryable dust map: dust_map().query(coord) returns E(B-V) at coord, vectorized over an array-valued coord.

Return type:

dustmaps.planck.PlanckGNILCQuery