Illustration of NASA’s Europa Clipper spacecraft
NASA/JPL-Caltech
IN OCTOBER, NASA’s Europa Clipper spacecraft is due to start its journey to explore Jupiter’s ice-encrusted moon Europa (imagined above in illustration).
NASA asked the scientific organisation that I lead, METI International, to draw on our expertise at attempting to contact extraterrestrial intelligence and help craft a symbolic missive engraved on a tantalum plate attached to the spacecraft – greetings from one water world to another.
We helped create two parts of the message. First, we collected a globally representative sample of audio recordings of the word for water in 103 languages, showing each as a waveform on the outward-facing side of the panel (shown above) that protects sensitive scientific instruments.
On the other, inward-facing side (shown below), we designed the scientific part of the message. This describes water in terms of the “water hole”, the band of frequencies between the hydrogen and hydroxyl (which combine to form water) emission lines in the radio spectrum where many early searches for intelligence beyond Earth were conducted.
Other parts of the interior message include: the Drake equation, which estimates the number of extraterrestrial civilisations in our galaxy; a microchip with the names of 2.6 million endorsers, to be added closer to launch; and US poet laureate Ada LimÓn’s poem to Europa, which ends: “O second moon, we, too, are made / of water, of vast and beckoning seas… / of a need to call out through the dark.” The Europa Clipper is due to enter Jupiter’s orbit in April 2030.
Douglas Vakoch, president of METI International
Topics:
- Jupiter/
- space exploration