all the heavy
elements that we find on Earth were
originally synthesized that's made
inside
Stars
astronomers are now studying the
mechanism in which these elements are
formed inside the
stars now they know that somewhere in
the universe there will be every element
or at least the on that are not
radioactive inside different stars but
the problem is to detect a particular
element in a star and some elements like
the element tum had not been discovered
in Stars before now just to remind you I
need to put a glove on here here is the
sample of tum in fact there are two
samples there's one here inside this
block and there's a rather nice
bell-shaped
piece and you can see that tum when you
look at it on earth a large lump looks
rather like a silvery metal it's not a
metal it's so-called
semiconductor but it shines rather like
a metal the reason why I'm using a glove
is because if you absorb tum in your
body it gives you terrible smells coming
out of your body which I don't want and
you probably don't either I can pick up
a lamp like this and I in principle I
can do analysis and show its
tum Brady found a recent press release
here from MIT Massachusetts Institute of
Technology announcing that some of their
astronomers had discovered evidence for
the existence of
torium in a star now the press release
was clearly not written by a chemist
because it began Rare Earth element
found in Far Far Away and tuum is not a
rare earth but we can forgive them
that and there's a paper which talks
about detection of the second R process
R stands for Rapid Peak
element tuum in metal poor Stars this is
a physics journal so I don't know the
meaning of all those things but
the actual experiment they did is quite
easy to
understand now as you can guess the only
thing that you can measure easily from
the star is the light that is coming
from it you can't travel there with your
test tubes what the basis for this
experiment is is that every
element will have a characteristic
fingerprint of the wavelengths of light
that it can absorb so you can look at a
little peak of absorption and say that's
tum or that's chromium or that's iron
now unfortunately for this particular
experiment the region in which tum
absorbs is very short
wavelength ultraviolet light round about
230 nanm or 2,300 angstrom units this is
a region where the Earth's atmosphere
absorbs
so the crucial light that you need to
detect tum is absorbed in the atmosphere
so if you point your telescope from the
ground at the star you just can't see
anything you can't tell whether there's
tum there or not so what they did was to
use the Hubble telescope which is out in
space so there's no air in the way and
so they can look at the stars without
worrying about the absorption here is
their
Spectra from three different
stars and this is the wavelength round
about
2385 angstrom units so you can see
there's a really tiny tiny piece of the
spectrum here
and these Peaks here show where light is
being absorbed and you can see there are
a lot of them it's like looking for a
tree in the
forest and there're three of these
because they're from three different St
Stars which have these rather unromantic
names of HD and then a lot of numbers
the important Peak is
here you can see it's not very big but
that Peak there convinces the scientists
that they have found tum in the stars
now from the point of view of chemistry
this is not terribly important chemists
are only interested in lumps of tum and
using it to make Chemical
so the fact that it is in stars that are
so far away that nobody could possibly
ever travel
there is an interesting fact for the
coffee room but it's not something that
is going to lead to a whole new area of
chemical production on the other hand
the more we can understand about how our
universe originated and how the elements
originated is valuable it's a very good
test of the theories of how elements are
formed and so on and the aim of science
is to try and improve the picture of the
world or the universe we live in and
it's never finished because once we have
got the broad outline there are always
details to be filled in and sometimes
those details will show that theories
are wrong a lot of scientists even if
they're not astronomers are fascinated
by astronomy I'm quite interested by by
it but I feel so sick and get such big
headaches when I look through a
telescope that I've never or feel
glasses that I've never really done much
astronomy but it is a very sobering
thought to realize that there are these
enormously complicated processes that
have occurred millions of light years
away billions of years ago that have
proc created the chemicals that we're
using today and if you want to find out
more you can go to Brady's new channel
called Deep sky videos all about what
happens in the depths of space and there
is the website written right there so go
and have a look at it or you can keep
watching periodic
videos plenty to say about it but also
as a special treat for this video we're
going to be using that the Isaac Newton
telescope to take an image of it these
are nice to see probably better image
with something like a DSLR camera cuz
you can capture the star colors fairly
quickly and before they start doing some
real work so let's head down