Phosphine Data Which Hinted At Possible Life On Venus Also Inspired Musical Composition
Clara Sousa-Silva spent years figuring out how to detect phosphine on different planets. In September, she was part of the research team that found phosphine in the atmosphere of Venus. But her phosphine research also inspired composer David Ibbett, who turned the spectral data into musical compositions.
“When I first started studying phosphine, it was known for being horrible on Earth,” says Sousa-Silva. Phosphine has been used as a fumigant or a chemical warfare agent, but that wasn’t why Sousa-Silva was interested in it. She turned her attention to phosphine on other planets, rather than Earth. “Phosphine is really hard to make,” she explained, “but on planets like Jupiter and Saturn you can reach the temperature and the hydrogen pressure for phosphine to be made spontaneously.”
Still, detecting phosphine wasn’t straightforward, so Sousa-Silva devoted her PhD to figuring out phosphine’s spectral fingerprint. She simulated 16.8 billion spectral features for phosphine – these were the patterns you would expect to see in your data if phosphine was around. “They’re a representation of how the molecule vibrates,” she adds.
But while phosphine could be formed in a lab or in the extreme conditions around Jupiter and Saturn, there is another path to creating phosphine.
Early life on Earth wasn’t centered around oxygen, but was dominated by anaerobic organisms.
“This anaerobic life still exists on Earth,” says Sousa-Silva. “It’s always in the shadows: at the bottom of lakes, in swamps, in marshland, and in the intestines and excrement of almost any animal – ourselves included.”
Crucially, wherever you find anaerobic life on Earth, you can find phosphine. In fact, Sousa-Silva’s research suggested that any rocky planet that contained measurable amounts of phosphine could only have formed those through biological processes.
So when astronomer Jane Greaves found one of the spectral features of phosphine in Venus’ atmosphere, she turned to Sousa-Silva to figure out what it could mean. They looked for possible other reasons that could explain the presence of phosphine, but couldn’t find any, so last September the news broke that maybe there was a possible sign of life on Venus.
Sousa-Silva is the first to admit that there are still many uncertainties about the finding. “Maybe I missed something,” she says. “Maybe it’s another molecule mimicking the signal, or maybe the signal isn’t real.” The hunt is now on to find one of phosphine’s other 16.8 billion signature features.
Meanwhile, on Earth, composer David Ibbett was using phosphine spectral data for a very different purpose.
“I’ve been interested in sonification for some time,” he says. Sonification is the process of turning data into sound. He became fascinated with the type of work that Sousa-Silva was doing and used her phosphine spectral signatures as the building blocks for musical compositions.
“The first thing I did was to take that data and come up with musical chords by taking the ratios between the spectral features and turning those into a harmony.” He demonstrates on the piano. “It has this broad feature in the longer wavelengths, which becomes this sort of cluster sound.” Ibbett plays a low chord on the piano. “And then there are three distinct peaks, which are shorter wavelengths,” he adds, while playing three higher notes. “Initially, I used that to create this atmospheric piece called ‘Earth Has Been Many Planets’.” This piece represents the atmosphere of the Earth over time, as it moved from phosphine life to being dominated by oxygen-based life.
But this week, a newer Ibbett composition based on Sousa-Silva’s phosphine work will premiere at the Other Skies festival, where cellist Minjin Chung will perform “Phosphine: Life Anaerobic”. This new piece is inspired by the concept of life that thrives in a phosphine-rich environment.
Sousa-Silva has already heard a preview of the work, and was struck by how much it reminded her of some of the molecular properties of phosphine. She explains that if you look closely at the spectral pattern of a molecule like phosphine, you see a substructure within the bands, called rovibrational structure. These patterns are caused by the movements of the phosphine atoms within the molecule.
“And although I hadn’t explained this to David, I felt it in the music because it has these overwhelming arcs of sound within the general tones that feel very much like the rovibrational substructures.”
Ibbett’s compositions give a new interpretation on scientific data that can make work like Sousa-Silva’s perhaps feel slightly more tangible to an outsider. But even Sousa-Silva herself looked at her research in a new way after hearing the compositions. Normally, she works alone and her work can feel quite abstract. But, she adds, “I didn’t quite realise how much nicer it is when you have other ways of experiencing your work.”
The Other Skies Festival, including a talk by Sousa-Silva and Minjin Chung’s performance of “Phosphine: Life Anaerobic” will be held on Saturday, March 20th.
Published at Thu, 18 Mar 2021 22:34:46 +0000