Days One & Two
If someone had told me that you can estimate the size
of the meteor that created a particular impact crater
just by dropping a 1.75 kilo steel ball into sand, I’d
have told them they were talking rubbish. But it can
be done. The first two days of this challenge involved
me doing just that. For this programme, Kathy, Iain
and I have been given the job of working out the size
(diameter) of the meteorite that produced the particularly
large impact crater in the Nevada Desert. While Kathy
and Iain were away in Nevada working out the actual
size of the crater, my job was to create a series of
much smaller craters using a much smaller meteorite.
All I had to do was drop a steel ball of known weight
from known heights and plot the diameter of the impact
craters that I formed against the energy of the impact,
which can be calculated since you know the height from
which you’re dropping the ball. By going to greater
and greater heights you can get more and more impact
energy. From just a few data points, it’s possible
to estimate the size of the meteorite that will produce
a particular crater size. The idea is to extrapolate
from my small-scale results to the larger scale of the
Nevada crater.
OK, there are other processes going on in real meteorite
impacts, such as the meteorite exploding – something
that we could never reproduce experimentally under Rough
Science conditions. Even so, this extrapolation method
might still work well enough for our purposes
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