Many researchers argue that microbial life beyond Earth is not only possible but likely, given several recent discoveries in planetary science. Three major lines of evidence support this optimistic view.
First, methane repeatedly detected in the Martian atmosphere may indicate the presence of living microorganisms. On Earth, a significant portion of methane is produced biologically, especially by microbes that thrive in oxygen-poor environments. Since the methane on Mars appears and disappears in seasonal patterns, many scientists interpret it as a strong hint that the gas is being generated by active microbial communities beneath the planet’s surface.
Second, two icy moons—Europa of Jupiter and Enceladus of Saturn—are now considered among the most promising habitats for extraterrestrial biology. Both bodies possess vast subsurface oceans of liquid water, warmed by tidal heating and shielded from space by thick ice. Observations of hydrothermal-like activity on Enceladus suggest that these oceans could closely resemble Earth’s deep-sea vent systems, which are known to support rich microbial ecosystems independent of sunlight. If similar chemical and thermal conditions exist there, microbial colonies could easily persist.
Third, scientists studying distant exoplanets have identified atmospheric combinations—such as the simultaneous presence of oxygen and methane—that may serve as biosignatures. These gases generally coexist only when continuously replenished by living organisms. Because modern telescopes are capable of detecting such atmospheric patterns from many light-years away, the probability of identifying a biologically active planet has grown substantially.
Taken together, these discoveries provide compelling support for the hypothesis that microbial life may be widespread in the universe. Although direct proof remains elusive, the existing evidence strongly suggests that Earth is unlikely to be the only world where life has emerged.
Step 2. Listen to part of a lecture below and take notes.
Although many scientists believe that simple life forms might exist elsewhere in our solar system, several lines of evidence suggest that this optimism is misplaced. In fact, recent research seriously challenges the idea that microbial life is likely to be found beyond Earth.
First, supporters of extraterrestrial microbes often point to chemical signatures such as methane detected on Mars. However, new geochemical models show that the methane can be produced entirely through non-biological processes, including reactions between minerals and ultraviolet radiation. These models can reproduce the methane patterns almost exactly, leaving no compelling reason to interpret the gas as biological.
Second, the subsurface oceans of Europa and Enceladus are often described as promising environments, yet recent measurements indicate that these oceans may be extremely low in usable chemical energy. Without constant sources of energy, microbial communities cannot sustain themselves. Unlike Earth’s hydrothermal vents, where chemical energy is abundant, the ocean floors of these moons may be too chemically inert to support life.
Finally, even atmospheric “biosignatures” expected on distant exoplanets are far from reliable. Laboratory simulations have demonstrated that oxygen–methane combinations, thought to indicate biology, can arise from purely volcanic activity when specific temperature and pressure conditions are present. These false positives make it very difficult to distinguish true biological signals from natural planetary chemistry.
Taken together, these findings suggest that claims about extraterrestrial microbes rely on overly optimistic interpretations of ambiguous data. While the search should continue, the current scientific evidence offers little support for the idea that life is common beyond Earth.
• Contradict = Oppose
• Contest = Criticize = Call into question
• Counter (instead of refute)
• Reject (instead of refutes)
• Undermine (instead of challenge)
• Contend (instead of argue)
• Highlight = Clarify
• Rebuke (instead of refute)
• Observe (instead of note)
• Propose = Present
• Illuminate = Emphasize = Illustrate
[Overview] The lecture contradicts the theories presented in the reading passage regarding [Topic].
[Body] Firstly, it contests the hypothesis that [Hypothesis from Reading], contending that [Contradictory Point from Lecture].
Secondly, it undermines the idea of [Second Idea from Reading] by clarifying that [Contradictory Point from Lecture].
Finally, it calls into question the theory of [Third Theory from Reading], observing that [Contradictory Point from Lecture], proposing [Alternative Explanation from Lecture] as a factor.
2. Write an Email
You will read some information and use it to write an email.
You will have 7 minutes to write the email.
Read the Task: 1:00
A local yacht club offers sailing courses for adults and accepts both beginners and experienced sailors. You are interested in enrolling in a training program but need more information before making a decision.
You plan to contact the administration of the yacht club to clarify several points.
Write an email to the yacht club administrator. In your email, do the following:
Request information about tuition fees for their sailing courses.
Ask whether students are allowed to train using their own yachts.
Specify the model and type of your yacht and ask if the club works with such yachts.
Write as much as you can in complete sentences.
Your email should be polite and clear.
I am writing to inquire about [briefly state the purpose of the email].
I recently learned about [the organization / service / course], and I am
very interested in the opportunities it offers.
In particular, I would like to request further information regarding
[fees / conditions / availability / procedures].
I would also appreciate it if you could clarify whether
[specific request or condition] is possible.
Additionally, I would like to inform you that [relevant personal detail or specification],
and I was wondering whether your organization works with or accommodates
[this type / model / situation].
I would be grateful if you could let me know [what action or confirmation you are expecting]
at your convenience. Thank you in advance for your time and assistance.
Yours faithfully,
[Your Name]
3. Independent writing
Reading time – 2 minutes, writing time – 8 minutes
Step 1. Read the academic discussion
Read the post carefully: 2:00
Professor’s Post (Topic):
In recent years, governments and private companies have invested billions of dollars in space technologies: launching new satellites, planning missions to Mars, and even developing space tourism. Supporters argue that these projects drive innovation, create jobs, and help us understand our place in the universe. However, critics point out that many societies still struggle with poverty, inadequate healthcare, and the effects of climate change, and they question whether expensive space programmes are morally justified when so many urgent problems remain unsolved on the ground. In your view, should governments continue to allocate significant public funds to space exploration, or should they redirect that money to more immediate needs on Earth?
Esmeralda
I believe that governments should keep investing heavily in space exploration, even if there are serious problems on Earth. Many everyday technologies, from medical imaging to satellite navigation, originally came from space research, so cutting these programmes could slow progress in many other fields. In addition, space missions often require international cooperation, which can reduce political tensions and create shared goals. For me, the long-term benefits of scientific discovery and technological innovation justify the expense.
Claudio
Personally, I think it is difficult to defend huge space budgets while basic social needs are not fully covered. When hospitals are underfunded and many people cannot afford education or housing, spending billions on rockets seems irresponsible. Of course, some level of space research is useful, but it should not receive priority over essential services that directly affect people’s lives today. In my opinion, governments ought to reduce large, ambitious space projects and focus more on solving problems here on Earth first.
Step 2. Write a response (about 120 words) stating your opinion on the issue. Be sure to:
State your own view clearly. It brings you more points if your opinion is different from those of the students.