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Eight new sources of cosmic x-rays were detected by two Aerobee surveys in 1964. One source, from Sagittarius, is close to the galactic center, and the other, from Ophiuchus, may coincide with Kepler's 1604 supernova. All the x-ray sources are fairly close to the galactic plane.

At least 30 discrete cosmic x-ray sources have been detected thus far. The distribution is concentrated toward the galactic plane, and most of the sources are believed to lie within 2 kiloparsecs of the sun. It is estimated that the average luminosity of the observed sources is about 5 x 10(36) ergs per second and that the entire galaxy contains about 1250 such sources. Comparisons of fluxes observed over the course of the past 2 years reveal that many sources are highly variable.

The x-ray flux from the Crab Nebula was observed during a lunar occultation on 7 July 1964. As the moon covered the central region of the nebula, the x-ray flux decreased gradually. The source appears to extend over a volume about 1 light-year in diameter.

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