UPSC Essentials has launched a new initiative featuring subject-specific quizzes aimed at aiding candidates in revising critical topics from the static syllabus. Engage with today’s quiz focused on Science and Technology to assess your knowledge and progress.

Prepare for the UPSC Prelims 2026 by utilizing our Special Quiz Magazine, designed to enhance your study strategies and improve your revision efficiency. (Click Here)

Considering the Voyager 1 mission, please evaluate the following statements:

1. It was initially launched to explore the inner planets, such as Mercury and Venus.
2. Voyager 1 has proven instrumental for researchers seeking insights into conditions in interstellar space and the heliosphere.
3. This spacecraft is powered by a radioisotope thermoelectric generator that converts heat from decaying plutonium into electrical energy.
4. It was launched by NASA in 2010.

How many of the above statements are accurate?

Significance: Missions like Voyager 1 frequently feature in the news due to their significant achievements, making them relevant for the UPSC Prelims, particularly in the context of space technology. Questions typically assess knowledge of space exploration instruments like RTGs and concepts such as the heliosphere. Candidates should familiarize themselves with notable space missions covered in the media.

— NASA has made the challenging decision to deactivate one of Voyager 1’s long-standing scientific instruments, as the spacecraft faces a critical power shortage.

— Launched in 1977, Voyager 1 stands as one of the most pivotal space missions in history. Although its primary objective was to study the outer planets, including Jupiter and Saturn, the mission has far exceeded its original goals. Now, it is the most distant human-made object in space, traveling swiftly through interstellar territory. Thus, statements 1 and 4 are incorrect.

— Over time, Voyager 1’s function has shifted. Presently, it provides valuable data about interstellar conditions and the heliosphere, the region beyond the Sun’s influence. Together with its counterpart, Voyager 2, it remains the only probe capable of delivering direct information from this largely unexplored zone. Therefore, statement 2 is accurate.

— The decision to switch off the instrument suite was driven by the clear need for power conservation, as Voyager 1’s energy resources had become insufficient for all its systems. The spacecraft relies on a radioisotope thermoelectric generator that converts heat from decaying plutonium into electricity. However, the energy output has been steadily declining since launch, with approximately 4 watts diminishing each year. Hence, statement 3 is also correct.

Consequently, the correct answer is option (b).

Regarding the hantavirus, which of the following statements are true?

1. It is named after a river located in South Korea.
2. It comprises a group of rodent-borne viruses that can lead to severe illness and death in humans.
3. Transmission can occur through contact with contaminated surfaces.
4. It can easily be transmitted between humans.

Select the correct answer using the codes provided below:

Significance: Zoonotic diseases are crucial topics for the UPSC Prelims in the health category. Questions evaluate knowledge regarding transmission methods, reservoirs (rodents), and public health threats. Understanding emerging infectious diseases and their connections to human-animal interactions is also relevant.

— The local government of Spain’s Canary Islands, situated near Morocco, announced a ban on a luxury cruise ship whose passengers have been affected by a serious hantavirus outbreak.

— Hantavirus, named after the Hantan River in South Korea, represents a group of rodent-borne viruses capable of causing significant illness and mortality in humans. Notably, the rodents carrying the virus do not suffer from the illness themselves. Thus, statements 1 and 2 are accurate.

— Human infection typically occurs through exposure to the urine, feces, or saliva of infected rodents, or by touching contaminated surfaces. According to the U.S. Centers for Disease Control and Prevention (CDC), airborne transmission can also happen if viral particles from droppings are inhaled. Therefore, statement 3 is correct.

— Generally, hantaviruses do not spread easily between humans. However, there have been instances of human transmission related to the Andes strain found in Argentina and Chile. It is suspected that the individuals aboard the cruise ship contracted the Andes hantavirus. As a result, statement 4 is incorrect.

— Hantavirus pulmonary syndrome (HPS) is primarily found in the Western Hemisphere and is associated with New World hantaviruses, which are the more lethal variant, resulting in a one-third fatality rate among those who develop respiratory symptoms. The disease can escalate from flu-like symptoms to severe respiratory complications, diarrhea, and vomiting.

— Haemorrhagic fever with renal syndrome (HFRS) is another category of diseases caused by Old World hantaviruses, predominantly affecting regions in Europe, Africa, and Asia. HFRS impacts approximately 150,000 individuals each year, with a mortality rate ranging between 1% and 15%. The Hantaan and Dobrava strains are particularly dangerous, while infections from the Seoul, Saaremaa, and Puumala viruses tend to have milder effects.

Therefore, the correct answer is option (d).

Which of the following exhibits wave-particle duality, meaning they exist in both particle and wave forms?

Select the correct answer using the codes provided below:

Significance: This question assesses conceptual understanding, which is crucial for distinguishing between options in interdisciplinary inquiries related to modern physics and its applications. It aids in differentiating fundamental entities from macroscopic phenomena.

— Both light and matter demonstrate wave-particle duality, existing simultaneously as both particles and waves. Recent experiments have also indicated that antimatter similarly exhibits this duality.

Each particle of matter has a corresponding mirror twin, which is nearly identical but carries an opposite charge. When the two…