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Unit TestLIFE
(plus)
ON VENUS
Life on Venus
A Is it possible that there was once life on Venus?
Recent space exploration has shown that our
neighbouring planet was possibly much more
similar to Earth in the past, with a 1plate tectonics
system and oceans which could have contained
primitive life forms.
B Until recently we have never been able to get a
close view of Venus, due to its 450ºC temperature
and the fact that it’s covered in a thick layer of
poisonous gas. However, in 2007 the European
Space Agency (ESA) sent a probe to orbit around
Venus and photographed it using 2infra-red cameras
which can see through these clouds. The images
revealed that Venus probably has ancient continents
produced by volcanic activity and which used to be
surrounded by seas. It seems that for some reason
Venus’s climate went out of control and became
drastically hotter, and it is hoped that studying its
climate change may help us understand climate
change on Earth.
C The infra-red photos of Venus tell scientists what the
planet’s surface might be made of because different
rock types radiate different levels of heat and show
up as different colours. The images revealed patches
of lighter rock in highland areas, which on Earth are
usually associated with continental crust and 3felsic
rocks like granite.
DIf these pale rocks on Venus are indeed granite, it
is possible that they were created under similar
1 Answer the questions in your own words.
1 In what ways may Venus have once been similar to
conditions to those on Earth. Granitic rocks usually
require water for their formation, so these findings
suggest that, early in the history of the Solar System,
Venus may have been a habitable planet with
plenty of water. Granite is an 4igneous intrusive
rock, meaning it solidifies below the Earth’s surface.
Although geologists have some doubts about how
granite is produced, one mechanism is when heavy
basaltic oceanic 5lithosphere is subducted under
lighter continental crust at a plate boundary. As it is
drawn down, heat and pressure cause it to melt and
it mixes with debris and water which were carried
under along with the crust, and then, as it cools, it
recrystallizes as granite. After millions of years of
erosion this granite is finally revealed at the surface
of the continentals.
E Of course, none of this conclusively proves that
Venus was once a more hospitable planet. All we
really know is that the plateau rocks look different
from elsewhere and therefore may be granitic.
Despite this, scientists think it is worth searching
for microbial life which may still be living in
Venus’s lower atmosphere. It is uncertain why Venus
suddenly became so hot and dry and whether the
same could one day happen to Earth. For now we
just have to consider ourselves lucky that we live
on a planet with the perfect temperature – halfway
between boiling Venus and freezing Mars.
4 Match words 1–5 in the text with definitions a–e.
a a type of light that is warm but cannot be seen
breferring to rock with a high content of silica
Earth?
minerals, such as quartz
2 How is granite created on Earth?
c referring to rock formed from molten magma
da theory which explains the movement of
2 Are the statements true or false? Quote words
from the text to support your answers.
1 The surface of Venus can be seen from Earth with a
telescope.
2 Scientists aren’t sure there is no life on Venus today.
e the part of the Earth which includes the crust
and the upper mantle
1 to move around a large object in space in a circular
or elliptical motion.
3 Rewrite the sentences without changing the
meaning.
1 He regrets not studying for the geology exam.
He wishes
2 I asked Mark to help me, but he wouldn’t.
Photocopiable
volcanic and seismic activity
5 Find words in the text that mean the same as …
Even
the Earth’s continents and the distribution of
2 the outer layer of the Earth found under the
continents and the oceans.
3 a common coarse-grained rock.
4 when one of the Earth’s plates is drawn under
another.
5 a raised area of land.
This page is a sample taken from Upgrade Teacher’s Resource Book 2, Mike Sayer © Macmillan Publishers Limited 2010.
This page may be photocopied for use in class.