7 Quiz
Answer the following questions to test your understanding of the key ideas you have learned in this course.
Activity 5
a.
The potential for crewed missions to travel to Mars
b.
The increasing prevalence of space debris orbiting Earth
c.
The exploitation of resources on the Moon from polar regions
d.
The protection of Earth’s environment from asteroid impacts
e.
The search for life and its building blocks
The correct answers are a, c and e.
Answer
The prevalence of space debris within Earth’s orbital environment is not a reason behind planetary protection, although it is important that the space sector considers carefully how they use the space environment sustainably and responsibly. Protecting Earth from asteroidal impact is also not associated with planetary protection.
a.
A mineral produced because a microbe changes the local chemical and physical conditions
b.
The presence of a gas in a planetary atmosphere
c.
The predominance of light stable isotopes within rock samples
d.
The presence of L-alanine in higher abundances than D-alanine
The correct answer is b.
Answer
The presence of a gas in a planetary atmosphere is not a biosignature. It might imply the presence of life, but it needs to be detected around a specific area of the planet, or at difference times.
Question 3
Match the type of extremophile to the environmental condition it can thrive within.
Using the following two lists, match each numbered item with the correct letter.
-
psychrophiles
-
alkaliphiles
-
halophiles
-
piezophiles
-
hyperthermophiles
Match each of the previous list items with an item from the following list:
a.temperatures 80–121 °C
b.temperatures <15 °C
c.very dry conditions
d.pH 8-12.5
e.high salinity
- 1 = b,
- 2 = d,
- 3 = e,
- 4 = c,
- 5 = a
a.
The possibility of habitable environments on the target body
b.
The potential presence of organic molecules formed without the presence of life
c.
The type of mission (flyby, orbiter, lander)
d.
The duration of the mission
e.
Whether samples will be returned to Earth
The correct answers are a, b, c, d and e.
Answer
All of these factors are taken into consideration when assigning a mission’s category, including the duration of the mission, since this determines the period of biological exploration and the potential for contamination.
a.
I
b.
II
c.
V ‘restricted’
d.
IV
e.
V ‘unrestricted’
The correct answer is e.
Answer
A sample return mission from a comet is likely to be a Category V ‘unrestricted’. Although comets are known to contain organic molecules, scientific opinion deems them to have no indigenous life for backward contamination to pose a risk. The Stardust mission that collected samples from Comet Wild-2 was a Category V ‘unrestricted’ mission but had outbound planetary protection requirements equivalent to Category II, that is, the comet was considered of interest to the origin of life, but the possibility of contamination was considered to be low risk.
a.
True
b.
False
The correct answer is a.
a.
COPUOS
b.
NASA’s Office for Planetary Protection
c.
COSPAR Panel on Planetary Protection
d.
UKSA’s Planetary Protection Advisory Panel
e.
International Astronomical Union
The correct answer is c.
Answer
The COSPAR Panel on Planetary Protection maintains and updates the Planetary Protection Policy on the basis of emerging scientific evidence.
a.
Number of organic molecules in an air sample
b.
The number of particulates that settle on a surface
c.
The presence of bacteria
d.
Number of spores per unit area
e.
The number of human skin cells
The correct answer is d.
Answer
The number of spores per unit area is used as a measure of bioburden. Spores are a proxy for all microorganisms that might be present on a spacecraft.
a.
Dry heat
b.
Application of alcohol on wipes
c.
Plasma sterilisation
d.
Gamma radiation
e.
Acid bath
The correct answer is e.
Answer
An acid bath is not used for minimising bioburden because this would be potentially destructive to the sensitive parts of a spacecraft.
a.
True
b.
False
The correct answer is b.
Answer
False. Crewed missions are subject to planetary protection requirements, but this has been identified as an area that needs more scientific investigation.