The data made available through this page have been superseded by the Green et al. 2018 reddening map, which is available here
Reddening (E(B-V)) Map (Green et al. 2015)
HEALPix nested, res 11 (Nside=2048)
3.4 to 13.7 arcmin
Original Data Source
Green et al. (2015) derived a three-dimensional map of dust reddening to a distance of several kpc from Pan-STARRS1 and 2MASS stellar photometry. The map covers almost the entire sky north of declination -30 degrees, mostly at a resolution of 3.4 to 13.7 arcminutes. It is based on Pan-STARRS1 photometry for 800 million stars and matching 2MASS photometry for about 200 million of these stars. The three-dimensional data can be queried or downloaded from the 3D dust mapping site of Green, Schlafly, and Finkbeiner. This site provides the following notes on the three-dimensional data.
LAMBDA provides a two-dimensional map of the cumulative reddening to the farthest distance bin for each pixel. This was calculated as the median over the Markov chain samples in the 3D dataset for the farthest distance bin, following the method given here. We also provide a 1-sigma uncertainty for the cumulative reddening. Following a recommendation from Gregory Green, this was calculated as half of the difference between the 84th percentile cumulative reddening sample and 16th percentile sample, with a floor of 0.03.
The two-dimensional reddening map is available as a binary FITS table, ordered according to the HEALPix scheme. The original three-dimensional dataset contains data for pixels of different sizes. The two-dimensional data have been upsampled to the minimum pixel size (HEALPix res=11, or Nside=2048). The data are set to NaN for unobserved pixels. Each record in the table has the following fields:
For the inner Galactic plane, the 3D extinction map of Marshall et al. 2006 may also be of interest. This map penetrates to larger distance, but with poorer angular resolution.
More details can be found in:
A Three-dimensional Map of Milky Way Dust", Green, Schlafly, Finkbeiner et al. 2015, ApJ, 810, 25. ADS