Using France's Convection Rotation and Planetary Transits (CoRoT) space telescope, Michel and a bevy of colleagues from Europe and South America measured the stars' light output over a 60-day period.
CoRoT reads stellar vibrations as changes in brightness.
The team found that the three stars have vibrations that are 50 percent more energetic than the sun's.
The stars also have surface granulations about three times finer than the sun's.
The observed oscillations are close to what astronomers predicted based on computer models, but are about 25 percent weaker than expected.
"This is not so bad and even gratifying," Michel said, adding that the results fall within the margins of uncertainty built into the models.
The data are described in this week's issue of the journal Science.
The study authors add that the results would not have been possible using observatories on the ground, because Earth's atmosphere obscures minute variations in starlight.
For them, the new data illustrate the importance of continued space-based observations.
(See the first 3-D images of the sun taken in 2007 by a pair of orbiting telescopes.)
Michael Montgomery, a stellar physicist at the University of Texas in Austin, wrote a commentary on the new study that also appears this week in Science.
"This [paper]," he said, "bodes well for the future of space-based seismology programs while simultaneously challenging us to refine our models of these stars."
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