Astronomy Picture of the Day

Discover the cosmos! Each day a different image or photograph of our fascinating universe is featured, along with a brief explanation written by a professional astronomer.

June 30, 1996
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Greetings from the Pioneers
Credit: courtesy Pioneer Project, ARC, and NASA

Explanation: Launched in the early 1970s Pioneer 10 and 11 were appropriately named - becoming the first spacecraft to travel through the asteroid belt, first to fly by Jupiter and Saturn, and the first human artifacts to venture beyond the solar system. Now coasting through interstellar space, they carry with them greetings in the form of a gold anodized plaque with symbolic drawings as illustrated above. The male and female figures are drawn to the same scale as the Pioneer spacecraft shown behind them. Immediately to the left is a map of the position of the sun with respect to nearby pulsars and the center of the galaxy while below is a drawing of the solar system indicating the planet of origin. In the upper left is a schematic of two fundamental states of the hydrogen atom. These diagrams along with other details of the plaque were designed by Carl Sagan of Cornell University and are intended to be decipherable by spacefaring extraterrestrial civilizations.

Tomorrow's picture: Worlds of a Distant Sun


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Authors & editors: Robert Nemiroff (GMU) & Jerry Bonnell (USRA).
NASA Technical Rep.: Sherri Calvo. Specific rights apply.
A service of: LHEA at NASA/ GSFC