The seas are supposed
to be the
result of
condensation of water
vapour originating
from the Earth
itself. Now, there is
evidence that the
water may have a
cometary source:
the Earth's outer
surface is being
constantly showered
with gigantic
snowballs weighing
20-40 tonnes at
a,6te of close to
43,000 per day. The
snowballs
disintegrate and
evaporate harmlessly in
the outer atmos
phere, some
1,000-24,000 kin above
the Earth's surface,
eventually com
ing down as rain.
Calculations show
that this water could
account for the
oceans over billions
of years.
The evidence comes
from the National Aeronautics
and Space
Administration's
orbiting space-
craft, Polar. The
data was interpreted
by a research team
led by Louis
A Frank of the
University of Iowa,
US. Frank had first
suggested this
bombardment I I years
ago. At that
time, it had been
dismissed by most
scientists as
ridiculous. The expla-
nation was required
to account for
dark holes in the
Earth's atmos-
phere photographed by
Polar.
According to the
explanation, the
holes were a result
of absorption of
solar radiation by
the snowballs
when they hit the
atmosphere and
evaporated.
Scientists agree that
the
evidence will have to
be confirmed
since it has wide
ramifications. For
in-stance, the
concept of the hydro-
logical cycle will
need rethinking.
We are a voice to you; you have been a support to us. Together we build journalism that is independent, credible and fearless. You can further help us by making a donation. This will mean a lot for our ability to bring you news, perspectives and analysis from the ground so that we can make change together.
.png)
Comments are moderated and will be published only after the site moderator’s approval. Please use a genuine email ID and provide your name. Selected comments may also be used in the ‘Letters’ section of the Down To Earth print edition.