Standing here on the surface of the Earth (only a handful have ever stood elsewhere), we think of our Sun as a generator of light and of heat -- but not of sound, for, naturally, we simply can not hear it. Photons need no medium to travel through; but sound is simply a series of compression waves, and something must be there to be compressed. And so, to a person awakening in a windowless chamber, with no external light reaching in, no clue would reach across the vacuum of space to inform as to whether their corner of the Earth was facing toward or away from the Sun.

But we know from the crackling of a campfire (or a greater conflagration) that burning of things produces audible sounds. Even a light bulb simply giving off light makes a sound in so doing, though for a low wattage bulb this is likely too faint to hear. So what would it sound like to stand on the surface of the Sun? Well, the Sun is actually one enormous ongoing nuclear explosion -- equivalent to about 100 billion one megaton bombs constantly going off. Concussive force -- whether perceived as sound or simply as a tactile sensation (the familiar vibrational 'feeling' accompanying loud noises) is expressed in decibels, though the most familiar usage of that measure is in respect to compression waves detected audibly. Indeed, Movement occurring in any environment -- whether it be gaseous, liquid, solid, or mixed -- imparts energy into that environment. It is unusual to think of sound waves as simply energy, but this is essentially what they are. Concussive forces which we feel but which is not necessarily audibly perceptible (or not primarily perceived that way) are often called shock waves, though the transmission is the same kind of force.

Fortunately, there exists a formula for converting acoustic decibels into decibels of force, and converting those decibels of force into wattage -- 0 db = 10-12 watts/meter2 (an arbitrary bottom determined by what is traditionally deemed the lowest audible sound), and dBW = 10log10W. The discharge of energy which is the source of the Sun's luminosity would be the same discharge of energy which produces vibration as well -- which somebody sitting on the surface of the Sun would perceive as sound. And so, the afrementioned formulae leads us to understand that since, according to NASA the Sun generates 386 yottawatts (3.86e+26 watts) of luminosity per second, and since its luminosity results from a direct nuclear conversion of matter to energy, the Sun's 'surface' (were it perfectly spherical and neatly defined) would roar along at a constant 170 dB. Remember that decibel measurements are logarithmic -- that is, something which is 50 decibels is one tenth as 'loud' (has one tenth the compression) of something which is 60 decibels. The Sun does have an atmosphere of sorts, reaching a few tens of thousands of miles beyond the typical edges of its flames. Mariner 10, launched in 1973 to survey Venus and Mercury, at one point came within 3000 miles of the surface of the sun, and there recorded sounds exceeding 165 decibels.

But standing directly on the surface of the Sun, even if all of its heat and radiation and soul-crushing gravity were somehow shunted away from you, would still yield instant death from the sheer shock of the noise, like a billion jet engines all exploding at once, all around you, endlessly. And because this level of noise would shake any solid object down to its component atoms, no device capable of recording or transmitting sound would withstand it long enough to register anything more than its own instant destruction.

Now, suppose the planets floated not in a relative vacuum, but in some sound-compressing medium, perhaps the aether of the ancients. Earth being 93 million miles from the Sun, the inverse square dissipation of sound over distance would still yield a physically excruciating 125 dB on Earth's sun-facing side, and actually not much diminution at all on the nightside. Unlike light, which is utterly blocked by the opaque planet, compression would carry both through the solid elements of the Earth and around its atmosphere. Though only a fraction of what would be heard on the Sun's surface, that's still over a 100 times the sound of a jackhammer from a few feet away. Submarine life forms would fare little better. But then, if this had been the case since the beginning of organic life, we'd never have evolved to take note of or rely on sound, just as cave worms and cave snakes and the like have evolved to not rely on (or be affected by) light and fish have evolved to not drown in the water.

All this aside, if you really wanted a sampling of the sounds of the surface of the sun (beyond understanding that you're unlikely to perceive anything other than a raw and very low frequency noise), there is a theoretical way to do obtain it. One could possibly be created by bouncing a laser off the star and back to Earth (the angle being calculated with ridiculous precision, in consideration of the Earth's calculable orbital movement and rotation during the sixteen minute round trip the beam would be making), and then convert the digital signal returned into sound.

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Oolong has wisely pointed me to the Stanford Solar Center, and its intriguing information about the Sun having a its own ring, its compression waves traveling around its surface like a bell. Though the sheer volume of sound would overwhelm the ability of any listener to hear the amazing patterns of sound this produces, it turns out that they are not only measurable and recordable (with the assistance of technological augmentation to make them comprehensible to human ears), but have been recorded and are available to listen to in various formats.

ScienceQuest 2012