CAT 2024 Slot 3 · VARC · RC passage 2: Planetary Protection and Mars Exploration

The full passage and all 4 questions (Q7–Q10) from CAT 2024 Slot 3, with answers and solutions.

The passage below is accompanied by four questions. Based on the passage, choose the best answer for each question.

There is a group in the space community who view the solar system not as an opportunity to expand human potential but as a nature preserve, forever the provenance of an elite group of scientists and their sanitary robotic probes. These planetary protection advocates [call] for avoiding “harmful contamination” of celestial bodies. Under this regime, NASA incurs great expense sterilizing robotic probes in order to prevent the contamination of entirely theoretical biospheres ...

Transporting bacteria would matter if Mars were the vital world once imagined by astronomers who mistook optical illusions for canals. Nobody wants to expose Martians to measles, but sadly, robotic exploration reveals a bleak, rusted landscape, lacking oxygen and flooded with radiation ready to sterilize any Earthly microbes. Simple life might exist underground, or down at the bottom of a deep canyon, but it has been very hard to find with robots. . . . The upsides from human exploration and development of Mars clearly outweigh the welfare of purely speculative Martian fungi ...

The other likely targets of human exploration, development, and settlement, our moon and the asteroids, exist in a desiccated, radiation-soaked realm of hard vacuum and extreme temperature variations that would kill nearly anything. It’s also important to note that many international competitors will ignore the demands of these protection extremists in any case. For example, China recently sent a terrarium to the moon and germinated a plant seed—with, unsurprisingly, no protest from its own scientific community. In contrast, when it was recently revealed that a researcher had surreptitiously smuggled super-resilient microscopic tardigrades aboard the ill-fated Israeli Beresheet lunar probe, a firestorm was unleashed within the space community ...

NASA’s previous human exploration efforts made no serious attempt at sterility, with little notice. As the Mars expert Robert Zubrin noted in the National Review, U.S. lunar landings did not leave the campsites cleaner than they found it. Apollo’s bacteria-infested litter included bags of feces. Forcing NASA’s proposed Mars exploration to do better, scrubbing everything and hauling out all the trash, would destroy NASA’s human exploration budget and encroach on the agency’s other directorates, too. Getting future astronauts off Mars is enough of a challenge, without trying to tote weeks of waste along as well.

A reasonable compromise is to continue on the course laid out by the U.S. government and the National Research Council, which proposed a system of zones on Mars, some for science only, some for habitation, and some for resource exploitation. This approach minimizes contamination, maximizes scientific exploration ... Mars presents a stark choice of diverging human futures. We can turn inward, pursuing ever more limited futures while we await whichever natural or manmade disaster will eradicate our species and life on Earth. Alternatively, we can choose to propel our biosphere further into the solar system, simultaneously protecting our home planet and providing a backup plan for the only life we know exists in the universe. Are the lives on Earth worth less than some hypothetical microbe lurking under Martian rocks?

Question 7 · RC Inference Questions

The author is unlikely to disagree with any of the following EXCEPT:
  1. A
    the proposal for a zonal segregation of the Martian landscape into regions for different purposes.
  2. B
    that while NASA’s earlier missions were not ideal in their approach to space contamination, they likely did no grave damage.
  3. C
    space contamination should be minimised until the possibility of life on the astronomical body being explored is ruled out.
  4. D
    the exorbitant costs of continuing to keep the space environment pristine may be unsustainable.
Pick an option, then check.
Answer & solution

Answer: Option C

'Unlikely to disagree with any EXCEPT' means: find the one statement the author would disagree with.

Option 1 – zoning Mars into regions – is the author's own 'reasonable compromise'.

Option 2 – earlier missions were not ideal but did no grave damage – fits his point that Apollo left litter and 'bags of feces' 'with little notice'.

Option 4 – the high cost of keeping space pristine may be unsustainable – fits his claim that strict sterility 'would destroy NASA's human exploration budget'.

Option 3 – minimise contamination until life is ruled out – is the planetary protection position he argues against. He calls the biospheres 'entirely theoretical' and says human exploration 'clearly outweigh[s] the welfare of purely speculative Martian fungi'.

Shortcut: decode the double negative first – 'unlikely to disagree with all EXCEPT' = 'the author would disagree with'. Then look for the option that states the view the passage attacks.

Hence, the answer is option 3.

Question 8 · RC Detail and Fact Based Questions

The author mentions all of the following reasons to dismiss concerns about contaminating Mars EXCEPT:
  1. A
    the lack of evidence of living organisms on Mars makes possible contamination from earthly microbes a moot point.
  2. B
    efforts to contain contamination on Mars are likely to be derailed as competitor countries may not follow similar restrictions.
  3. C
    the use of similar probes on astronomical bodies like the moon have had little effect on the environment.
  4. D
    earlier explorations have already contaminated pristine space environments.
Pick an option, then check.
Answer & solution

Answer: Option C

The author gives these reasons to dismiss contamination concerns: Mars is a 'bleak, rusted landscape' with no proven life (option 1); international competitors such as China 'will ignore the demands of these protection extremists' (option 2); and earlier missions already contaminated space – Apollo left 'bacteria-infested litter' on the moon (option 4).

Option 3 says similar probes on the moon have had little effect on the environment. The author never says this. His moon argument is that it is a 'desiccated, radiation-soaked realm' that would kill nearly anything, and his contamination example is human waste from Apollo, not probes.

Shortcut: in a 'reasons mentioned EXCEPT' question, match each option to a specific sentence. The option that combines real words from the passage (probes, moon) into a claim the passage never makes is the exception.

Hence, the answer is option 3.

Question 9 · RC Tone and Attitude

The author’s overall tone in the first paragraph can be described as
  1. A
    sceptical about the excessive efforts to sanitise planets where life has not yet been proven to exist.
  2. B
    equivocal about the reasons extended by the group of scientists seeking to limit space exploration.
  3. C
    indifferent to the elitism of a few scientists aiming to corner space exploration.
  4. D
    approving of the amount of money NASA spends to restrict the spread of contamination in space.
Pick an option, then check.
Answer & solution

Answer: Option A

The first paragraph describes planetary protection advocates as wanting the solar system to be 'a nature preserve, forever the provenance of an elite group of scientists', and says NASA 'incurs great expense sterilizing robotic probes in order to prevent the contamination of entirely theoretical biospheres'. The words 'elite', 'great expense' and 'entirely theoretical' show the author doubts the value of these efforts.

Option 1, sceptical about excessive efforts to sanitise planets where life is unproven, fits.

Option 2 (equivocal) is wrong; the author takes a clear side.

Option 3 (indifferent) is wrong; he is critical of the elitism, not indifferent to it.

Option 4 (approving of NASA's spending) is the opposite of his view.

Shortcut: in a tone question, collect the evaluative words – here 'elite', 'great expense', 'entirely theoretical'. If they lean one way, discard any neutral or opposite option.

Hence, the answer is option 1.

Question 10 · RC Inference Questions

The contrasting reactions to the Chinese and Israeli “contaminations” of lunar space
  1. A
    are valid as the contamination of the lunar environment from animal sources is far greater than from plants.
  2. B
    are evidence of China’s reasonable approach towards space contamination.
  3. C
    indicate that national scientists may have different sensitivities to issues of biosphere protection.
  4. D
    reveal global biases prevalent in attitudes towards different countries.
Pick an option, then check.
Answer & solution

Answer: Option C

China sent a terrarium to the moon and germinated a seed 'with, unsurprisingly, no protest from its own scientific community'. When tardigrades were smuggled aboard the Israeli probe, 'a firestorm was unleashed within the space community'. Similar acts drew very different responses depending on which scientific community was reacting.

Option 3 – national scientists may have different sensitivities to biosphere protection – captures that contrast.

Option 1 claims animal contamination is far worse than plant contamination; the passage makes no such comparison.

Option 2 calls China's approach 'reasonable'. The author uses China as an example of competitors who will ignore protection demands, not as a model.

Option 4 speaks of global biases against countries. The passage contrasts scientific communities' reactions, and nothing suggests bias against Israel as a country.

Shortcut: when a passage contrasts two reactions, look for the option that names who reacted. Here the key words are 'its own scientific community' versus 'the space community'.

Hence, the answer is option 3.

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