The Earth, Solar System, Stars and Universe as Musical Instruments

Modern scientists often study matter in terms of its vibratory nature, from the tiniest subatomic particles to the largest entities in the cosmos. The earth, the solar system, the stars, and the universe itself have all attained a scientific status as gigantic musical instruments.

Earth
The Earth creates a variety of unheard tones by vibrating in many different ways. Scientists include the slow vibrations of the Earth and its atmosphere in the study of acoustics.

Microseisms are waves of ground vibrations that continually travel across the Earth's surface. They behave, in effect, like minor seismic surface waves. However, microseisms are caused not by earthquakes but by the interaction of wind and ocean waves with the earth's crust, by volcanic disturbances, and by such human sources as motor vehicles and industrial machines. Such phenomena can be detected hundreds of miles from their sources. They generate a background of constant vibrations (noise) against which earthquakes must be distinguished on seismographs.

One kind of planetary oscillation is the earth tide, the rising and falling of the earth's crust in response to tidal forces, a combination of the earth's centrifugal force and the moon's (and, to a less degree, the sun's) gravitational force. The effect varies in different parts of the earth, in middle latitudes, for example, a surface point on the crust at high tide being about one foot more distant from the earth's center than the same point is at low tide, while at other latitudes the bulge may be six inches, three inches, or some other size.

The whole earth also has "free oscillations" in fundamental periods. "The earth, as a musical instrument, knows two fundamental notes to which her body naturally oscillates: one with a vibration period of 53.1 minutes, the other of 54.7 minutes. Of course none of these planetary chimes can be heard by naked ears in their original slow frequency, since they are about 20 octaves lower in pitch than the tones we know and therefore, unless transposed, resemble silent periodic earthquakes....The electronic ears 'listening' to this celestial music are very sensitive seismographs." (Murchie, 76)

Solar System
Other bodies and forces near the earth also emit vibrations. In fact, "a symphony of sound reverberates through our solar system." ("Cosmic Song")

The two Voyager spacecraft, launched in 1977, sent back a variety of radio waves from the solar system. Played through conventional loudspeakers, waves from the solar wind (charged subatomic particles put out by the sun) sound like whistles, hisses, and pops. Those from Saturn's magnetosphere make eerie whines and hissing clicks. "But when played through a music synthesizer at a higher speed than that at which they are received, the signals can be made to produce a slow, dreamy melody." ("Cosmic Song")

Stars
Stars, too, emit vibrations. The sun, our local star, is a massive musical instrument ringing like a gong.

Scientists studying the sun's surface have discovered oscillations that they believe come from acoustic waves inside the sun. Researchers have identified at least "80 overtones (different ways that the sun vibrates) with periods of two to eight minutes." Of course, "these waves are beyond the range of human hearing, and sound cannot travel through the vacuum of space." Nevertheless, scientists and musicians have attempted to transpose the sun's oscillations into audible music. ("Cosmic Song")

Distant stars also display sonic characteristics. In 1998 an intense blast of radiation from a newly discovered kind of star, a magnetar, electrified the earth's upper atmosphere, marking the first time that astronomers traced a local disturbance to a distant sun. Produced by a gigantic "starquake" on a magnetar 23,000 light-years from the earth, the blast was powered by a magnetic field 100 times stronger than any previously known in the universe. "After the initial blast, the star 'rang' in X-rays for several minutes, producing an 'unheard of' tone." (Cole, "Scientists," A3)

Universe
The universe, viewed as a whole, is also a musical instrument. Scientists believe that in the early universe, compression of "liquid light" in gravity wells set up sound waves, which some scientists have called "the oldest music in the universe." (Cole, "Cosmos")

That music still echoes throughout the universe in the form of cosmic background radiation, a constant hiss of microwave radiation left over from the big bang. Scientists who have studied that radiation theorize that the early universe was an expanding fireball that contained acoustic waves. "The fireball was, in effect, ringing like a bell." (Overbye)

Scientists have found four cosmic "notes," or vibration patterns, in the radiation left over from the early fireball. The notes fade in strength as they go higher, a fact that confirms "the theoretical predictions that the higher notes would be blurred and fade the way low notes persist longer than high notes when a bell is struck." (Overbye)

Even though people cannot hear the tones generated by the earth, the solar system, the stars, and the cosmic background radiation, scientists continue to record more and more data about the cosmic symphony.
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Cole, K. C. "The Cosmos Was Alive with the Sound of Matter." Los Angeles Times, May 11, 2000: B2.

---. "Scientists Trace Cosmic Blast to Unusual Star." Los Angeles Times, Sept. 30, 1998: A3+.

"Cosmic Song." Science Digest, Jan. 1982: 77.

Encyclopaedia Britannica Ready Reference 2004. (CD-ROM). Encyclopaedia Britannica, 2004.

Murchie, Guy. "Matter Music." Science Digest, Jan. 1982: 76+.

The New Grolier Electronic Encyclopedia. CD-ROM. Grolier, 1990.

Overbye, Dennis, New York Times News Service. "Astronomers View Universe at 300,000 Years Old." Riverside (Calif.) Press-Enterprise, May 26, 2002: A23.