Like musical instruments, STARS, through their natural oscillations or vibrations, can be transformed into an audible sound waves. Astrophysicists detect them through the science of asteroseismology or stellar seismology and then artificially boost the sounds to bring them into human hearing range, producing ghostly whistling, drumming, humming, or bell sounds, depending on their frequencies or speeds of vibration. Listen to a few here.
RR Lyrae stars are used as distance indicators ("cosmic lighthouses")
and tracers of galactic evolution.
Frequencies of the southern RR Lyrae star SS For were converted into
sound by Elisabeth Guggenberger. We followed this star in a multisite
campaign (from South Africa and Australia) in 2005.
This star shows a mysterious modulation of its light curve shape, and
the modulation can clearly be perceived in the sound file.
The actual frequencies were sped up by a factor of about 8 million
(shifted by 23 octaves) to bring them into the audible region for our
PG1159+035 is a star nearly on the stellar graveyard. In its inside it is already a white dwarf.
The pitch was multiplied with a factor of 2 million to produce the sound you hear.
The first sound is the pure stellar sound. In the second part of the sound file the consecutive radial orders of the stellar pulsation have been transformed into octaves, which makes them sound more harmonious to our human ears.
The star sound files were then fed into a new
scientific instrument called a CymaScope
which makes the periodicities in the star sounds
visible as periodic wavelets on the surface of
water, effectively rendering the sounds visible.
Credit: ESO European Southern Observatory
Guenter Houdek and Douglas Gough