An all-sky image generated from the USNO-A catalog. What is shown is the number of stars per square degree. Yellow corresponds to the highest density, and dark blue to the lowest. The yellow band across the middle of the image is the plane of our galaxy. Dark areas superimposed on the central band are clouds of dust and gas which obscure some of the stars from view. The two bright blobs below and to the right of center are the Magellanic Clouds.
Astrometry is the branch of astronomy concerned with the determination
of positions, proper motions, and parallaxes of solar-system bodies,
stars, and distant galaxies. Astronomers at USNO use the latest
instrumentation and methods to extend the accuracy and brightness
limits of astrometric catalogs and reference frames.
- USNO Image and Catalog Archive Server.