It’s summertime once again here at Goddard, and summer means two things: mixing it up a bit with a special summer Blueshift series and summer interns. I’m Faith, back for another summer at Goddard, and considering I’m a recent college grad freshly released from my liberal arts college, it seemed only appropriate to use this summer on Blueshift to delve into the surprisingly interdisciplinary world of astrophysics at NASA. But wait! Don’t let the distinct un-summeriness of the word ‘interdisciplinary’ scare you away – think of it instead as a summer stroll through the lesser known branches of astrophysics . You may just be surprised by the astrophysical relevance of that Philosophy or Studio Art major that seemed like such a good idea when you were eighteen…
First, a little quiz to kick us off:
What do Jodie Foster’s character in Contact, 20th century composer Gustav Holst and pop-culture icon David Bowie have in common?
a) Perfectly tousled blonde locks
b) A propensity for wearing extravagantly ruffled shirts and leather pants
c) A tendency to express their love of astronomy and/or space exploration through sound
d) A deeply engrained passion for astrology, vegetarianism, and madrigal music
You guessed it, the answer is c); although a) could probably be argued as well. The complexities of the Universe can be experienced and represented in variety of ways. In many cases the same astrophysical data can be shown as a photographic image, a plot, an equation, or a table, but the possibilities don’t stop there. So what about expressing the Universe through sound and, more interestingly, through music?
So today we’re embarking on a whirligig tour of just a few ways that sound and music have been used to enhance our study and experience of astrophysics. We’ll start with the more scientifically relevant examples and end with the, ummm… well, the more artistic variants. I can’t vouch for how aesthetically pleasing these various sounds of the Universe may be, but when it comes to music, beauty is, after all, in the ear of the beholder.
The vast majority of the information we can gather about the Universe comes to us in the form of light, or electromagnetic radiation. Photons, massless particles of light, act as little packets of information making their way through space at the speed of light to tell us something about the object or event that produced them. Each photon has a characteristic wavelength that is related to how energetic it is, placing it along the electromagnetic spectrum (radio waves, microwaves, infrared, visible, ultraviolet, x-rays, and gamma-rays). While the waves that make up light are fundamentally different than sounds waves, their similar characteristics make it so that it is relatively straightforward to translate light into sound. This process lies at the heart of a number of the examples of astronomical music we will be looking at.
For many, the mere mention of radio astronomy immediately brings to mind the classic sci-fi movie Contact. Jodie Foster’s character Ellie Arroway sports oversized headphones and scans the airwaves for signals of extraterrestrial life using the NRAO’s (National Radio Astronomy Observatory) Very Large Array in New Mexico while relaxing on the hood of her car as the sun sets serenely in the background. Oh the sweet life of a radio astronomer! In general, the science in the movie is really quite good (check out this interesting fact/fiction piece about the science of Contact), but NRAO is quick to point out that while it is in fact quite possible to translate the radio emissions of the Universe into audible sounds as they do in the movie, doing so has little to offer scientifically. Apparently computers are much better at identifying those telltale alien signals, patterns or oddities than your average caffeine-fueled radio astronomer. Go figure. Not to mention that static with the occasional high-pitched chirp is not exactly music to the ear.
However, just because computers are more efficient listeners doesn’t mean that it isn’t still fascinating to tune in every once in a while to see what the radio Universe is up to. Here at Goddard, the Radio Jove project has been providing hundreds of students and amateur radio astronomers around the world the chance to listen in to Jupiter, the Sun and other interesting radio sources through its radio telescope kits. There’s nothing quite like listening to relativistic electrons spiraling along the galaxy’s magnetic field lines (even if it does just sound like static). Click here to listen for yourself!
Alas, there is so much more to the music of the Universe than just what we ‘hear’ in light. Physicist Janna Levin from Barnard College presents a fascinating TED Talk about how black holes can “bang on space-time like mallets on a drum”. According to Einstein’s theory of General Relativity, the Universe is composed of a four dimensional fabric called space-time that can be warped and bent out of shaped by objects with mass, much like a trampoline would sag in the middle if a bowling ball were placed on it. Black holes are extraordinarily massive objects, and thus they warp space-time significantly.
Now picture a binary black hole system in which two black holes are gravitationally bound to each other and are rapidly orbiting their shared center of mass. As the two objects swing round each other through space-time at close to the speed of light they cause ripples in space-time, known as gravitational waves, to emanate out from that location. This squeezing and stretching of space-time closely resembles the way sound waves propagate through a compressible medium; the difference being that sound waves squeeze and stretch mediums such as air or water as opposed to the very fabric of the Universe. Levin explores what such dramatic events might ‘sound’ like where the waves ‘loud’ enough for our ears to register. In fact, the National Science Foundation’s Laser Interferometer Gravitational-wave Observatory (LIGO) is currently trying to pick up these extremely faint waves in space-time, as will the Laser Interferometry Space Antenna (LISA), a space-based joint project between NASA-ESA.
Terry Riley’s “Sun Rings”:
Moving right along, the Kronos Quartet, a high-profile chamber ensemble, teamed up with NASA and University of Iowa physicist Don Gurnett to produce a musical piece entitled “Sun Rings” inspired by radio signals from various Solar System phenomena captured by Voyager, Cassini, and Galileo. Composer Terry Riley remarks, “To me, it’s quite miraculous when you imagine that, for instance, some of the sounds we’re using are from Uranus. Who could ever imagine that you could send a recorder to Uranus, record those sounds, and send them back to Earth, and it can actually appear in a concert hall as part of a piece?” The result is quite spacey…
Also check out Blueshift’s podcast on a similar project that used data from Fermi to inspire music!
Mickey Hart and George Smoot’s “Rhythms of the Universe”:
Even you die-hard Deadheads don’t get left out of the fun as Mickey Hart, percussionist of The Grateful Dead, teamed up with George Smoot of the Lawrence Berkeley National Laboratory (and co-recipient of the 2006 Nobel Prize in Physics with Goddard’s own John Mather!) to do a little extragalactic music of their own. This odd couple worked together to convert electromagnetic radiation from the Big Bang into music, a process about which Hart had the following to say, “I knew sooner or later I would have to hear and play with the sound of the ‘Big Bang,’ beat one, the beginning of time and space…this is where we came from.”
Gustav Holst’s “The Planets”:
In my personal opinion, a little tasteful anthropomorphism can go a long way in making science relatable and exciting, and that is just early 20th century compose Gustav Holst did with his seven-movement orchestral suite “The Planets”. Holst composed a separate movement for each planet (not including Earth or Pluto, which wouldn’t be discovered for another 15 years), creating a unique personality for each planet. However, Holst was himself a devotee of astrology and so devised each planet’s character based on their astrological influence on one’s psyche as opposed to on the Roman deities they were named after. Despite this breach of pure astrophysics, the suite succeeds in giving the planets new personality, depth, and beauty.
David Bowie’s “Space Oddity”:
David Bowie first caught the public eye in July of 1969 with his song “Space Oddity”. There may not be much actual science in it, but if nothing else it’s a creative look at space exploration.
This classic video even got a reference at last week’s U2360° concert in Seattle when NASA Commander Mark Kelly appeared from the International Space Station, closing with the line: “Tell my wife I love her very much… she knows.”
Mickey Moonlight’s “Interplanetary Music”:
And finally we have Mickey Moonlight’s cover of Sun Ra’s song “Interplanetary Music”. I’m not going to presume to have any thing terribly intellectual to say about this particular piece. Make of it what you will…