UPSC Essentials | Daily subject-wise quiz : Science and Technology MCQs on Atomic clocks, OSIRIS

Are you preparing for UPSC CSE Prelims 2026?

Check your progress and revise your topics through this quiz on Science and Technology.

UPSC Essentials brings to you its initiative of subject-wise quizzes.

These quizzes are designed to help you revise some of the most important topics from the static part of the syllabus.

Attempt today’s subject quiz on Science and Technology to check your progress.

With reference to the Atomic clocks, consider the following statements:
1.

These combine a quartz crystal oscillator with an ensemble of atoms to achieve greater stability.

2.

These are used onboard GPS satellites that orbit the Earth.

3.

Atomic Clock achieves stability by using germanium ions.

How many of the statements given above are correct?

Relevance: Precision instruments like Atomic clocks are important in Science & Technology, especially in navigation and communication systems.

UPSC can frame questions to test understanding of scientific principles and correct examples of technologies.

— India’s regional navigation system has been plagued by problems affecting its positioning data.

The Indian Space Research Organisation (ISRO) on Friday (March 13) informed that the atomic clock of one of the five remaining satellites that were still providing this data stopped working — meaning positioning data from the satellite IRNSS-1F was also lost.

— Atomic clocks combine a quartz crystal oscillator with an ensemble of atoms to achieve greater stability.

Hence, statement 1 is correct.

— In an atomic clock, the frequency of the quartz oscillator is transformed into a frequency that is applied to a collection of atoms.

If the derived frequency is correct, it will cause many electrons in the atoms to change energy levels.

If the frequency is incorrect, far fewer electrons will jump.

This will determine if the quartz oscillator is off-frequency and by how much.

A “correction” determined by the atoms can then be applied to the quartz oscillator to steer it back to the correct frequency.

— Atomic clocks are used onboard GPS satellites that orbit the Earth.

Up to 50 times more stable than the atomic clocks on GPS satellites, NASA’s Deep Space Atomic Clock is intended to be the most stable atomic clock ever flown in space.

It achieves this stability by using mercury ions .

Hence, statement 2 is correct and statement 3 is not correct.

Therefore, option (b) is the correct answer.

(Other Source: http://www.nasa.gov )
With reference to the Very Low Earth Orbit (VLEO), consider the following statements:
1.

It is relatively safe from collisions with space debris.

2.

Satellites operating in this range provide superior imaging and lower latency for 6G.

Which of the statements given above is/are correct?

Relevance: Emerging domains like Very Low Earth Orbit are important under Science & Technology, especially with growing satellite launches and private space activity.

UPSC can ask conceptual questions linking orbit types with their applications and advantages.

— Very Low Earth Orbit (VLEO), situated at an altitude between 100 and approximately 450 km (most commonly 250-350 km) is becoming increasingly attractive for both commercial and scientific endeavours.

— VLEO is relatively safe from collisions with space debris, as objects naturally decay and re-enter Earth’s atmosphere at an accelerated rate due to residual drag.

Hence, statement 1 is correct.

— Satellites operating in this range provide superior imaging and lower latency for 6G.

Hence, statement 2 is correct.

— However, operating at such altitudes comes with challenges, such as shortened lifespans due to residual atmosphere, active orbit maintenance, surface erosion from atomic oxygen and short communication windows.

Therefore, option (c) is the correct answer.

With reference to the Deep Ocean Mission, consider the following statements:
2.

It focusses on sustainably harnessing ocean wealth and strengthening the Blue Economy.

3.

The United Nations named the 2021-2030 decade as the ‘Decade of Ocean Science for Sustainable Development’.

4.

India’s first manned submersible vehicle ‘MATSYA 6000’ is being developed as part of the Samudrayaan Project under Deep Ocean Mission.

Relevance: The Deep Ocean Mission is a key initiative under India’s push for the Blue Economy, making it important for Prelims.

It connects with themes like ocean resources, marine technology, and sustainable development, frequently asked in Science & Tech and Geography.

— Deep Ocean Mission, launched in 2021 , focusses on sustainably harnessing ocean wealth and strengthening the Blue Economy.

Hence, statement 1 is not correct and statement 2 is correct.

— India’s first manned submersible vehicle ‘MATSYA 6000’ is being developed as part of the Samudrayaan Project under Deep Ocean Mission.

Hence, statement 4 is correct.

— The Deep Ocean Mission was launched on 07.09.2021 by the Ministry of Earth Sciences (MoES) with an aim to develop technologies for exploring and sustainably utilizing the deep ocean’s living and non-living wealth.

— The United Nations named the 2021-2030 decade as the ‘Decade of Ocean Science for Sustainable Development’.

India’s unique geography, with 7517 km of coastline, nine coastal states, and 1382 islands, gives it an edge in the sector.

Hence, statement 3 is correct.

(Source: http://www.pib.gov.in )
With reference to the OSIRIS-REx mission, consider the following statements:
1.

The mission was launched by Nasa in collaboration with the European Space Agency.

2.

The mission targeted the Trojan Asteroids.

Relevance: Space missions like OSIRIS-REx are frequently asked in Prelims under Science & Technology (space sector).

It links static concepts with current developments in asteroid exploration, planetary science, and space competition.

— OSIRIS-REx is the first U.S.

mission to collect a sample from an asteroid.

It returned to Earth on Sept.

24, 2023, to drop off a capsule with material from asteroid Bennu .

Hence, statements 1 and 2 are not correct.

— After dropping off the sample capsule through Earth’s atmosphere, the spacecraft was renamed OSIRIS-APEX and sent on a new mission to explore asteroid Apophis in 2029.

Therefore, option (d) is the correct answer.

Consider the following statements about ‘HbA1c’:
1.

It is a blood test that shows your average blood sugar levels over the past two to three months.

2.

An HbA1c above 5.7 per cent is considered normal.

3.

It is commonly used to assess long-term glucose control in individuals already diagnosed with diabetes.

Relevance: With the rising burden of Diabetes Mellitus in India, understanding diagnostic tools like HbA1c is important for public health awareness.

It links static concepts with current affairs related to government health initiatives and screening programs.

— Both HbA1c and fasting blood glucose are important tests, but they serve different purposes in understanding blood sugar levels .

— HbA1c is a simple blood test that shows your average blood sugar levels over the past two to three months.

An HbA1c below 5.7 per cent is considered normal .

A value between 5.7 per cent and 6.4 per cent indicates prediabetes.

An HbA1c of 6.5 per cent or higher, confirmed by two separate tests, is a diagnosis of diabetes.

Hence, statement 1 is correct and statement 2 is not correct.

— The typical target is to keep HbA1c below 7 per cent, although this may vary based on age.

— Consistently high HbA1c levels are linked to long-term complications affecting the eyes, kidneys, nerves, and heart.

— HbA1c is commonly used to assess long-term glucose control in individuals already diagnosed with diabetes.

It helps doctors see whether blood sugar levels have been consistently high, even if a single fasting test appears normal.

Hence, statement 3 is correct.

Topic: War in the Middle East – Where is it headed, and what happens now
Is US & Israel justified in attacking Iran?

What will be new Supreme Leader Mojtaba Khameini’s strategy?

How does west Asia view the war?

How is India’s position on the war perceived by different nations?

How far is it going to impact India’s economy and its diaspora in the region?

Join us in the next edition of Explained.Live with Navdeep Suri, Former Indian Ambassador to UAE & Egypt in conversation with Shubhajit Roy, Diplomatic Editor, The Indian Express
Register now: https: //zoom.us/webinar/register/9017733199890/WN_GLNpxRb6SqyjNrW4Ut81Mg
March 19, 2026 | 5:30 PM | Zoom
Previous Daily Subject-Wise-Quiz
Daily Subject-wise quiz — History, Culture, and Social Issues (Week 149)
Daily subject-wise quiz — Polity and Governance (Week 154)
Daily subject-wise quiz —  Science and Technology (Week 153)
Daily subject-wise quiz — Economy (Week 153)
Daily subject-wise quiz — Environment and Geography (Week 153)
Daily subject-wise quiz – International Relations (Week 153)
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