Essays should be between 1500 and 2000 words. The word limit should include the text,
figure captions, footnotes, but not the reference list (we are happy to see lots of references).
You will lose marks for going more than 10% over the limit of 2000 words.
The format of the essay is not specified. You are welcome to include section headings and
pictures. However, try to ensure that they help to illustrate the argument presented in the
essay and are not mere adornment.
Your essay should be written for a well-informed but non-specialist audience. The style (not
the format) used in popular science magazines such as Scientific American or New Scientist
would be a suitable guide. Remember, you are not writing for experts, so if you use technical
jargon you will need to explain it. Refrain from using formulae, but instead explain concepts
in your own words.
Essays will be graded on:
• Degree of understanding of the topic (max. 6 marks)
• Quality and depth of research (max. 6 marks)
• Clarity of presentation (max. 6 marks)
• Outstanding original coverage of the topic (max. 2 marks)
Essays are expected to show evidence of researching the topic beyond the material presented
in the course lessons and textbook. They are expected to be more than just a literature review
– they should present the understanding of the subject that you have developed.
The sources you use (websites, journal articles, books) should be referenced. You should
consistently use one of the standard reference styles. One style is to number references
sequentially in the text and include a numbered list of references at the end of the essay. An
alternative is to mark references in the text using author and date – e.g (Sagan, 1987) or
Drake et al. (1965) – and list references at the end of the essay in alphabetical order.
“References” here are the sources that you have used to understand a particular point. You
may have also done wider reading that informs your general background – if you wish, you
may present this in an additional bibliography. Such a bibliography is optional, and not a
requirement. A list of references is a requirement.
If you use text directly from another source you must make it clear that it is a quote by
placing it in quotation marks (“ ”) and giving a reference to the source. However, you should
not make excessive use of quotes. Direct quotations use up word count, and (in the main) will
not contribute to your grade, because the essay will be assessed on the extent to which you
have identified, understood and interpreted background information, and then and presented
your views on the subject – not on your ability to find relevant information and quote it.
Essay Topics — Choose one of the following:
- Space Telescopes
Explain why astronomers put telescopes in space. Describe the Hubble Space
Telescope and some of its achievements. How will the forthcoming James Webb
Space Telescope differ from Hubble and what new science should be possible with it.
- The Earliest Evidence for Life
Review the earliest evidence for life on Earth. What form does the evidence take and
where is it found? Discuss the controversies relating to some of this evidence and give
your conclusion on the earliest date at which we can be confident that life was present
- Follow the Water
Why do astrobiologists think that liquid water is the most important requirement for
life? What is the evidence for the past presence of liquid water on Mars? Is it possible
that there is still liquid water on Mars today?
- Life in Extreme Conditions
Explain what extremophile life forms are and where they are found on Earth. In view
of what we have learnt about extremophiles discuss the possibility of extra-terrestrial
life in different places of our Solar system.
- Key Solar System Planetary Missions
Choose ONE of the following space missions and give an account of the mission
describing the challenges it had to overcome and the mission’s achievements.
Describe in particular how it has influenced our understanding of the possibilities of
past or present life in the solar system.
• The New Horizons mission to Pluto and beyond
• The Galileo orbiter/probe mission to the Jupiter system.
• The Cassini/Huygens mission to the Saturn system.
- Gravitational Waves
On Feb 11 2016 the announcement was made of the detection of gravitational waves
from space using the Advanced LIGO facility. What are gravitational waves? How
does LIGO detect them and why is this discovery significant?
- Small Solar System Bodies
Describe how space missions have been used to study small Solar system bodies
(comets and asteroids). What have we learned about these bodies? How might such
studies help us understand the origin of life on Earth?
- Inside stars
Explain how helioseismology and solar neutrinos help to study interior of the Sun.
Based on two examples, a low mass star like our Sun and the star that is twenty times
more massive than the Sun, discuss how the internal composition of the stars changes
during their life.
- Formation of planetary systems
Discuss the early ideas about the formation of our Solar system. Compare our solar
system with other multi-planetary systems discovered in the last 20 years. Explain
what we have learnt about formation of planets from these discoveries. Describe the
concept of planetary 16 migration.
- Kepler and TESS
Compare the strategy and objectives of the NASA Kepler mission and the NASA
TESS missions. Describe what observations are needed to confirm that an extra solar
planet has similar physical characteristics to our Earth, and the role of the Kepler and
TESS missions have had in the search for planets like the Earth.
- Habitability of Planets
Explain what makes a planet habitable. In the context of currently known extra solar
planetary systems discuss the likelihood of habitable planets in our Galactic
neighbourhood. Describe some examples of recently discovered extra solar planets,
which are suggested to be habitable and explain why.
- Role model astronomer/astrobiologist
Science advances by efforts of large collective of collaborating people, but there are
outstanding individuals that we all admire for their role in moving us forward in
understanding our world. Choose your favourite contemporary (that is born not earlier
than the twentieth century) astronomer or astrobiologist that you learnt about in
studying this course, and describe their contribution to their field of research. Explain
why this person inspired you personally.
- The Standard Cosmological Model Describe the standard cosmological model (also
known as the Lambda-CDM model of the universe). What is the observational
evidence that supports the model?
- The Search for Extra-Terrestrial Intelligence
Explain what is SETI and how it approaches the search for the extra-terrestrial
intelligence. Explain why radio telescopes are particularly useful in such a search. If
we contact an advanced extra-terrestrial civilization discuss how likely it is that we
will benefit from the encounter through, for example, the information they may
provide on advanced technologies, or are we likely to suffer through the hostility of a
species that competes for our resources and perhaps our planet? Should we be
advertising our presence, or would we be better keeping quiet? Factors you may wish
to consider could include:
• Do we expect another intelligent species to be friendly or hostile to other species?
• Have humans developed more, or less, tolerance of different cultures over time?
• The historical record of encounters between colonial and indigenous peoples.
• Our treatment of closely related species such as the great apes.
• The vast distances between stars and the difficulty of physical contact with extraterrestrial neighbours.
- Crewed Missions to Mars
There is discussion of sending a crewed mission to Mars in the near future. Discuss
the challenges such a mission will face, and how such a mission could be executed.
Describe possible benefits and drawbacks of such a mission in comparison with the
previous and future robotic exploration of Mars.