Illustration courtesy L. Calçada, ESO Published May 16, 2012 A
NASA spacecraft has witnessed hundreds of "superflares" coming
from sunlike stars—and the observations suggest that the trigger
for such massive outbursts remains a mystery. On our sun, solar
flares aimed at Earth can send huge amounts of energy colliding
with our planet. If a flare is strong enough, it can cause a
solar storm that might cripple satellites and even knock out the
power grid. Astronomers have also recorded similar but much more
powerful flares coming from a variety of stars. These
superflares can be millions or even a billion times more
powerful than an average sun eruption, packing enough energy to
roast nearby planets whole. It's not likely, but if a superflare
were to engulf Earth, for example, our protective ozone layer
would be instantly obliterated, said Brad Schaefer, an
astrophysicist at Louisiana State University (LSU) who wasn't
involved in the new study. With no more atmospheric ozone,
dangerous ultraviolet rays from the