Figure A

NASA's Europa Clipper spacecraft will carry a special message when it launches in October 2024 and heads toward Jupiter's moon Europa. The moon shows strong evidence of an ocean under its icy crust, with more than twice the amount of water of all of Earth's oceans combined. A triangular metal plate, seen here, will honor that connection to Earth.

The plate is made of tantalum metal and is about 7 by 11 inches (18 by 28 centimeters). Engraved on both sides, it seals an opening in the electronics vault, which houses the spacecraft's sensitive electronics. The side shown here features U.S. Poet Laureate Ada Limón's handwritten "In Praise of Mystery: A Poem for Europa," and will be affixed with a silicon microchip stenciled with more than 2.6 million names submitted by the public. The microchip will be placed at the center of the illustration of a bottle amid the Jovian system – a reference to NASA's "Message in a Bottle" campaign, which invited the public to send their names with the spacecraft.

The artwork includes the Drake Equation, which was formulated by astronomer Frank Drake in 1961 to estimate the possibility of finding advanced civilizations beyond Earth. Also featured is a reference to the radio frequencies considered plausible for interstellar communication, symbolizing how humanity uses this radio band to listen for messages from the cosmos. These particular frequencies match the radio waves emitted in space by the components of water and are known by astronomers as the "water hole." On the plate, they are depicted as radio emission lines.

The plate includes a portrait of one of the founders of planetary science, Ron Greeley, whose early efforts to develop a Europa mission two decades ago laid the foundation for Europa Clipper.

Figure A: a close-up view of the plate.

The other side of the plate, which displays audio waveforms of the word "water" can be seen here: PIA26063.

In the spirit of the Voyager spacecraft's Golden Record, which carries sounds and images to convey the richness and diversity of life on Earth, the layered message on Europa Clipper aims to spark the imagination and offer a unifying vision.

Europa Clipper, set to launch from Kennedy Space Center in Florida, will arrive at the Jupiter system in 2030 and conduct about 50 flybys of the moon Europa. The mission's main science goal is to determine whether there are places below Europa, that could support life. The mission's three main science objectives are to determine the thickness of the moon's icy shell and its surface interactions with the ocean below, to investigate its composition, and to characterize its geology. The mission's detailed exploration of Europa will help scientists better understand the astrobiological potential for habitable worlds beyond our planet.

For more information about Europa and Europa Clipper, go to: europa.nasa.gov