Hello. This is 6 Minute English from
BBC Learning English. I'm Neil.
And I'm Georgina.
Last November Nasa launched
a very unusual home delivery
service - a rocket carrying
four tonnes of supplies to the
ISS - the International Space Station.
Among the scientific equipment were
twelve bottles of red wine
from the famous Bordeaux
region of France.
The astronauts might have wanted
a glass of wine with dinner,
but the real purpose of
the bottles was to explore the possibility
of producing food and drink in space - not
for astronauts but for people
back on Earth.
In today's programme we'll be finding out
how growing plants in space
can develop crops
which are more productive and more
resistant to climate change here on Earth.
And we'll hear how plants can grow
in environments with little or
no natural light. But first,
today's quiz question: what was the first
food grown in space? Was it:
a) potatoes, b) lettuce, or c) tomatoes?
Well, in the film, The Martian, a stranded
astronaut grows potatoes on Mars.
I know it's
only a film but I'll say a) potatoes!
OK. We'll find out the answer later. Now,
you might be wondering how
it's possible to
grow plants without natural light.
British company Vertical Future
has been working on
this problem by developing indoor
farming methods in partnership
with Nasa.
Here's their Head of Research,
Jen Bromley, explaining the process
to BBC World Service
programme, The Food Chain:
Basically we use LED lighting and we use
LED lights that are tuned to
a specific wavelength.
So, if you image what the rainbow looks
like, the reason a plant looks
green is because
it's not using all the green light - it actually
reflects a lot of that back. So the reason
why it looks pink in here is because we're
actually only using red light and blue light
to grow the plants, and that essentially
tailors the light diet so that
the plants look kind of black
when you look at them because
they're not reflecting any light - they're
being super-efficient,
they're using up every photon
that hits them.
The lack of natural light in space means
that plants are grown using
LED lights - LED is
an abbreviation of 'light emitting diode'
- an electronic device that lights up when
electricity is passed through it.
On Earth plants look green because they
reflect back any light travelling
at a certain wavelength -
the distance between two waves of light
which make things appear
to us in the various
colours of the rainbow.
But when scientists control the
wavelengths being fed, plants
are able to absorb every
photon - particle of light energy,
making them appear black.
Each particle of light that hits the leaves
is absorbed and through
photosynthesis is
converted into plant food. Nasa
found that different colour
combinations, or light recipes,
can change a plant's shape, size
and even flavour.
But the lack of natural light isn't the
biggest obstacle to
growing food in space. Here's
Gioia Massa, chief plant scientist
at the Kennedy Space Centre
in Florida, to explain:
Microgravity is really challenging but
plants are amazing! They can
adapt to so many different
environments - we call this plasticity
because they can turn on or off
their genes to really
adapt to all sorts of conditions and that's
why you see plants growing
in different areas
on Earth - the same type of plant
may look very different
because it's adapting to the
environment in that specific location.
On Earth, plants use gravity to position
themselves - shoots grow up,
roots grow down. But this
doesn't apply in space because of
microgravity - the weaker pull
of gravity making things
float and seem weightless.
Plants can only survive in these
conditions due to their
plasticity - the ability of living
organisms to adapt and cope with
changes in the environment
by changing their biological
structure.
Plants adapt themselves to being
in space by manipulating their
genes - chemicals and
DNA in the cells of plants and animals
which control their development
and behaviour.
In the low-gravity atmosphere of space,
plants become stressed but
they adapt genetically.
And as a result they're stronger and
more resilient to other, less
stressful events
when they return home to Earth.
Like those bottles of red wine orbiting
Earth as we speak.
The effects of microgravity on
the wine's organic composition will be
studied and could hopefully
offer solutions for growing
food in Earth's changing climate.
So, Neil, if it wasn't red grapes, what
was the first food grown in space?
Ah yes, in today's quiz question I asked
what the first plant grown in space was.
I said, a) potatoes.
But in fact it was... b) lettuce - grown
over fifteen months on the ISS,
then eaten in fifteen
minutes in the first ever space salad.
Today we've been discussing the
possibilities of growing plants
in space using LED lights
- devices that use electricity
to produce light.
The energy needed for plants to grow is
contained in photons - or light
particles, travelling
at different wavelengths - distances
between light waves which
make things look different
colours.
Plants have evolved over millennia using
the strong gravity on Earth.
But this changes
in space because of microgravity - the
weaker gravitational pull making
things in space
float and seem weightless.
Luckily plants use their genes - the
chemicals in DNA responsible
for growth - to adapt to
new environments by changing their
biological structure - a process
known as plasticity.
All of which makes it possible for
astronauts to enjoy a glass
of wine and green salad in
space.
And genetically stronger plants
specimens to study back on Earth.
That's all for today but join us again soon
at 6 Minute English. Bye for now!
Bye!