Donald Charles Backer (November 9, 1943 – July 25, 2010) was an American astrophysicist who primarily worked in radio astronomy.

Backer then took post-doctoral positions first at NRAO in Charlottesville, Virginia (1971–1973), and then at NASA/GSFC in Greenbelt, Maryland (1973–1975).

[3][9] Backer was also a pioneer in Very Long Baseline Interferometry, a technique in radio astronomy used to achieve high angular resolution images of astronomical sources.

His efforts here were directed towards understanding Sagittarius A*, the supermassive black hole at the center of the Milky Way.

[10] These arrays are simple long wavelength telescopes that hope to detect the redshifted hydrogen line from a time very early in the history of the universe when hydrogen was neutral, and by doing so study the first objects that formed in the universe.