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NASA’s Europa Clipper spacecraft, headed to Jupiter’s ice-covered moon Europa in October 2024, will carry a laser-etched message that celebrates humanity’s connection to water. The message pays homage to previous NASA missions that carried related messages.
Because the president of Messaging Extraterrestrial Intelligence, or METI, Worldwide, I helped design the message on Clipper with two fellow members of our board of administrators: linguists Sheri Wells-Jensen and Laura Buszard-Welcher. METI Worldwide is a scientific group devoted to transmitting highly effective radio messages to extraterrestrial life.
We collected audio recordings in 103 languages, and we determined methods to convert these into waveforms that present these sounds visually. Colleagues from NASA etched these waveforms into the metallic plate that shields the spacecraft’s delicate electronics from Jupiter’s harsh radiation.
I additionally designed one other a part of the message that visually depicts the wavelengths of water’s constituents, as a result of water is so necessary to the seek for clever life within the universe.
Etching messages into spacecraft is not a brand new apply, and Clipper’s message suits right into a decades-old custom began by astronomer Carl Sagan.
In 1972 and 1973, two Pioneer spacecraft headed to Jupiter and Saturn carrying metallic plaques engraved with scientific and pictorial messages. In 1977, two Voyager spacecraft headed to Jupiter, Saturn, Uranus and Neptune bearing gold-plated copper phonograph information. These information contained tutorials in arithmetic and chemistry, in addition to music, photographs and sounds of Earth and greetings in 55 languages.
Water phrases
As water is crucial for all times on Earth, trying to find its presence elsewhere has been key to many NASA missions. Astronomers suspect that Europa, the place Clipper is headed, has an ocean beneath its icy floor, making it a major candidate for the seek for life within the outer photo voltaic system.
A part of the Clipper message options the phrase for water in 103 languages. We began with audio information collected on-line, however we then wanted to investigate these and discover an output that could possibly be engraved on a metallic plate. I ended up going again to among the methods I utilized in a few of my early psycholinguistic analysis, the place I explored how feelings are encoded in speech.
The 103 spoken phrases we recorded symbolize a worldwide snapshot of the range of Earth’s languages. The outward-facing facet of the Clipper plate reveals the phrases as waveforms that observe the various depth of sound as every phrase is spoken.
Every individual whom we recorded saying the phrase “water” for the waveform had a connection to water. For instance, the lawyer who contributed the phrase for water in Uzbek—”suv”—organizes an annual music pageant in Uzbekistan to lift consciousness of the desertification of the Aral Sea.
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The native speaker of the Catalan water phrase—”aigua”—hunts for exoplanets, discovering probably liveable planets that orbit different stars.
The Drake Equation
Clipper’s message additionally pays homage to astronomer Frank Drake, the daddy of SETI—the Seek for Extraterrestrial Intelligence—by bearing the Drake Equation, his namesake method. By drawing on scientific knowledge, in addition to some greatest guess hunches, the Drake Equation estimates the variety of extraterrestrial civilizations within the galaxy at the moment sending messages into the cosmos.
By one broadly quoted estimate, there are a tenth as many of those extraterrestrial civilizations as one’s common lifetime in years. If civilizations survive for 1,000,000 years, for instance, there must be about 100,000 within the galaxy. In the event that they final solely a century on common, scientists would estimate that about 10 exist.
Radio astronomers examine the universe by inspecting the radiation that chemical parts in area give off. They spend a lot of their time mapping the distribution of essentially the most considerable chemical within the universe—hydrogen.
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Hydrogen emits radiation at a sure frequency known as the hydrogen line, which radio telescopes can detect. Throughout Venture Ozma, the primary modern-day SETI experiment, Drake appeared for synthetic alerts on the similar frequency, as a result of he figured scientists on different worlds may acknowledge hydrogen as universally vital and broadcast alerts at that frequency.
The water gap
As our workforce developed our water phrases message, I spotted that the message would solely make sense if it have been found by somebody already accustomed to the contents inscribed on the plate. The Drake Equation would solely make sense if somebody already knew what every of the phrases within the equation stood for.
The Europa Clipper will crash into Jupiter or one in every of its different moons, with Ganymede or Callisto the main candidates. But when for some cause the mission adjustments and it survives that destiny, then people far sooner or later with a radically totally different cultural background and totally different language conventions could retrieve it millennia from now as an historical artifact.
To make sure we had no less than one a part of the message {that a} distant future scientist may have the ability to perceive, I additionally designed a pictorial illustration of the identical frequency that Drake used for Venture Ozma: the hydrogen line. We engraved this on the Clipper plate, together with a frequency known as the hydroxyl line.
When hydrogen (H+) and hydroxyl (–OH) mix, they type water. Scientists name the vary of frequencies between these strains the “water gap.” The water gap represents the a part of the radio spectrum the place astronomers performed the primary SETI experiments.
We displayed the hydrogen and hydroxyl strains utilizing their wavelengths within the Clipper message. The metallic plate additionally has diagrams exhibiting what hydrogen and hydroxyl appear like on the atomic stage.
We’re hoping that future chemists would acknowledge these chemical parts because the components of water. In the event that they do, we may have succeeded in speaking no less than just a few core scientific ideas throughout time, area and language.
Waveforms let our workforce tie the messages on the 2 sides of the Clipper plate collectively. On the water phrases facet, over 100 phrases are depicted by their waveforms. On the opposite facet, the wavelengths of hydrogen and hydroxyl—the constituents of water—are etched into the plate.
METI Worldwide funded the gathering and curation of the water phrases, in addition to my design of the hydrogen and hydroxyl strains, offering these to NASA without charge.
Whereas designing the message for the Europa Clipper, we acquired to mirror on the significance of water on Earth, and take into consideration why astronomers really feel so compelled to seek for it beneath the icy crust of Jupiter’s moon Europa. The spacecraft is scheduled to enter Jupiter’s orbit in April 2030.
