HEALPix: Hierarchical Equal Area isoLatitude Pixelization of a sphere

Health and cleanliness of the XMM-Newton science payload since launch

HEAO 1 A-2 low-energy detector X-ray spectra of the Cygnus Loop

HEAO 1 hard X-ray observation of clusters of galaxies and intracluster magnetic fields

HEAO 1 high-energy X-ray observations of Centaurus X-3

HEAO 1 high-energy X-ray observations of three bright transient X-ray sources H1705-250 (Nova Ophiuchi), H1743-322, and H1833-077 (Scutum X-1)

HEAO 1 measurements of the galactic ridge

HEAO 1 measurements of the galactic ridge

HEAO 1 observations of gamma-ray lines from a solar flare

HEAO 1 observations of high-energy X-rays from the Seyfert I galaxy MKN 509

HEAO 1 observations of quiescent X-ray emission from flare stars

HEAO 1 scanning modulation collimator discovery of an extended X-ray source at Cygnus A

HEAO 1 spectra of X-ray emitting Seyfert 1 galaxies

HEAO 3 discovery of Al-26 in the interstellar medium

HEAO 3 limits on the 44Ti yield in type I supernovae

HEAO 3 observations of strong variable 0.5-3 MeV emission from the Taurus region

HEAO 3 observations of the Crab pulsar

HEAO 3 upper limits to pulsed gamma-ray emission from PSR 1509 - 58 and PSR 0833 - 45

HEAO A-2 soft X-ray source catalog

HEAO-1 A2 Maps of the Hard X-ray Sky