Astronomers Use ALMA To Dissect Nearby Planetary System [ Watch
the Video ] Astronomers have made a breakthrough discovery in
understanding a nearby planetary system, giving clues about how
these systems form and evolve. Scientists used the Atacama Large
Millimeter/submillimeter Array (ALMA) to find that planets
orbiting the star Fomalhaut must be smaller than originally
thought. The high-resolution images show that both the inner and
outer edges of the thin, dusty disk have very sharp edges. This,
as well as computer simulations, have led the astronomers to
believe that the dust particles in the disk are kept within the
disk by the gravitational effect of two planets. The team also
found that the probable size of the planets is that they are
larger than Mars but no larger than a few times the size of the
Earth. “Combining ALMA observations of the ring’s shape with
computer models, we can place very tight limits on the mass and
orbit of any planet near the ring,” Aaron Boley, a Sagan Fellow
at the University