The oscillation periods of pulsating white dwarfs range from 100s to 1000s,
the corresponding frequencies are 0.01 to 0.001 cycles/second.
If we "speed up" the white dwarf pulsations by a factor of
86,400 (the number of seconds in one day) then the frequencies
enter the audible range. Sped up by this factor, one day passes in
just one second.
The following sound files are what pulsating white
dwarf stars would "sound" like if sped up in this way.
BPM 37093
The WET observed BPM 37093 (a massive, partially crystalline pulsating white
dwarf) in two campaigns - Xcov16 in 1998, and Xcov17 in 1999. Results from
these two campaigns showed a sequence of 10 periods. The first sound below
represents what BPM 37093 would 'sound' like if the data are sped up to bring
the vibrations into audible frequencies.
The first in each of the two pairs below is a continuous sample corresponding
to 12 days of unbroken data such as can be obtained by the Whole Earth
Telescope (WET). The second file in each pair simulates "observation"
at a single site. Each short segment is a single night's observation.
The WET sampling shows the full pattern which is much less obvious in the
single site examples.
GD385: Periods of 256.127 seconds and 256.332 seconds along with
a harmonic at 128.115 seconds. The period beats every 3.7 days.
ZZ Ceti: Two pairs of periods. The first pair, at 212.8 seconds,
beats up and down every 1.44 days. The second pair, at 274 seconds,
beats with a period of 1.67 days.
The sounds below are derived from published WET data. The gaps you hear are
times when no WET site was online because of clouds. Note that the fuzzy
static that you hear is noise in the data resulting from the faintness of the
stars.
PG 1159 -035 is a hot white dwarf that pulsates in over 125
identified modes. The data used to generate this sound file are from Winget
et al. (1991) (Ap. J. 378, 326): see the
WET Papers List; this
is paper number 5. The periods in PG 1159 range from 300 to 800 seconds,
with the strongest periods around 490-540 seconds. With these longer
periods, speeding up the sound file helps for playback on most computers
GD 358 is a pulsating helium-surface white dwarf that is the
richest of all the known white dwarf pulsators. Over 175 modes have been
detected in this star. See Paper 8 (Winget et al, Ap. J. 430, 839) for
a complete analysis of WET's first look at this star. Periods range from
120 to over 1000 seconds. This sound file was made from observations in
Xcov10, and is sped up so that 1 second covers 3 days worth of data.
Audiolizations