UPSC Essentials | Daily subject-wise quiz : Science and Technology MCQs on National Space Day 2025, brown dwarfs and more (Week 125)

QUESTION 1

Consider the following statements:

1. INS Udaygiri is the second ship of the Project 17A stealth frigates built by Mazagon Dock Shipbuilders Limited (MDL).

2. INS Himgiri is the first ship of the Project 17A ships which is constructed by Garden Reach Shipbuilders and Engineers (GRSE), Kolkata.

3. INS Udaygiri is the 100th ship designed by the Navy’s in-house Warship Design Bureau.

How many of the statements given above are correct?

(a) Only one

(b) Only two

(c) All three

(d) None

Explanation

— The Indian Navy simultaneously commissioned two Nilgiri-class stealth guided-missile frigates, the INS Udaygiri and INS Himgiri, at Visakhapatnam.

— INS Udaygiri is the second ship of the Project 17A stealth frigates built by Mazagon Dock Shipbuilders Limited (MDL) in Mumbai. INS Himgiri is the first of the Project 17A ships constructed by Garden Reach Shipbuilders and Engineers (GRSE), Kolkata. Hence, statements 1 and 2 are correct.

— In another major milestone for the Indian Navy, INS Udaygiri is the 100th ship designed by the Navy’s in-house Warship Design Bureau. Hence, statement 3 is correct.

— Both ships are the result of an industrial ecosystem spanning over 200 Micro, Small, and Medium Enterprises (MSMEs), supporting approximately 4,000 direct jobs and more than 10,000 indirect jobs, the MoD has said.

Project 17A

— Project 17A is an Indian Navy program to build seven advanced, multi-mission stealth frigates known as the Nilgiri-class frigates, designed by the Warship Design Bureau.

— INS Nilgiri is the first of seven frigates in Project 17A. INS Nilgiri is built by Mazagon Dock Shipbuilders Limited (MDL), Mumbai. This class of ships has an “integrated construction” philosophy, which involves extensive pre-outfitting at the block stages to reduce overall building periods.

Therefore, option (c) is the correct answer.

QUESTION 2

With reference to the brown dwarfs, consider the following statements:

1. These are curious celestial bodies that share some similarities with stars and others with planets.

2. They have enough mass to consistently fuse hydrogen, a process that heats a star and makes it shine.

3. They have atmospheres similar to gas giant planets such as Jupiter and Saturn.

4. They are easy to detect.

How many of the statements given above are correct?

(a) Only one

(b) Only two

(c) Only three

(d) All four

Explanation

— Brown dwarfs are curious celestial bodies that share some similarities with stars and others with planets. For instance, these objects form like stars from collapsing clouds of gas and dust. However, they do not have enough mass to consistently fuse hydrogen, a process that heats a star and makes it shine. That is why they are often known as “failed stars”. Hence, statement 1 is correct and statement 2 is not correct.

— They have atmospheres similar to gas giant planets such as Jupiter and Saturn. Their atmospheres can consist of clouds and molecules like H2O. Brown dwarfs can also be up to 70 times more massive than Jupiter. Hence, statement 3 is correct.

— Brown dwarfs can be difficult to detect as they are cold and faint. As a result, astronomers typically search for brown dwarfs orbiting companion stars, which often burn brighter. This also helps them study these celestial bodies because if a brown dwarf is part of a multiple system with a brighter star, the chances are they were formed out of the same material, at the same place and time. Hence, statement 4 is not correct.

Therefore, option (b) is the correct answer.

QUESTION 3

Which of the following are the components of the Integrated Air Defence Weapon System (IADWS) developed by the DRDO?

1. Quick Reaction Surface to Air Missiles (QRSAM)

2. Advanced Very Short Range Air Defence System (VSHORADS) missiles

3. High-power laser-based Directed Energy Weapon (DEW).

Select the correct answer using the codes given below:

(a) 1, 2 and 3

(b) 2 and 3 only

(c) 1 and 2 only

(d) 1 and 3 only

Explanation

— The ministry of Defence (MoD) said that the Defence Research and Development Organisation (DRDO) has successfully conducted the first flight-tests of an Integrated Air Defence Weapon System (IADWS). The test was conducted off the coast of Odisha, in which three different targets were simultaneously destroyed at different ranges and altitudes.

— The IADWS is a multi-layered air defence system, which includes three components — Quick Reaction Surface to Air Missiles (QRSAM), the advanced Very Short Range Air Defence System (VSHORADS) missiles, and a high-power laser-based Directed Energy Weapon (DEW).

— While QRSAM has been designed and developed by the DRDO, VSHORADS and DEW have been developed by Research Centre Imarat (RCI) and Centre for High Energy Systems and Sciences (CHESS) respectively, both Hyderabad-based facilities of the DRDO.

Therefore, option (a) is the correct answer.

QUESTION 4

The Himalayan Outpost for Planetary Exploration (HOPE) analog mission setup in:

(a) Tso Kar Valley (Ladakh)

(b) Spiti Valley (Himachal Pradesh)

(c) Chamoli (Uttarakhand)

(d) Pithoragarh (Uttarakhand)

Explanation

— The Indian Human Spaceflight Programme is a national initiative led by ISRO that intends to extend human presence throughout the solar system, beginning with human spaceflight flights to Low Earth Orbit (LEO) and attaining Indian Crewed Lunar Landing by 2040. This necessitates conducting systematic studies to collect the essential Indian subject data for tackling the many physiological, psychological, and operational issues associated with human space flight missions. In this sense, ground-based analogue missions in environments that simulate certain characteristics of a regular human space trip allow researchers to better understand the hazards to human health and performance.

— ISRO’s Human Space Flight Centre (HSFC) is in charge of this endeavour for the agency’s forthcoming human space missions. The HSFC team led the Ladakh Human Analog Mission (LHAM) in November 2024 and collaborated on the recently completed ten-day Isolation Study ‘Anugami’ with ISRO’s Gaganyatri in July 2025. Continuing this endeavour, on July 31, 2025, Dr. V Narayanan, Secretary, Department of Space, and Chairman, ISRO, inaugurated the Himalayan Outpost for Planetary Exploration (HOPE) analogue mission setup in Tso Kar Valley, Ladakh.

Therefore, option (a) is the correct answer.

(Source: http://www.isro.gov.in)

QUESTION 5

With reference to the National Space Day, consider the following statements:

1. August 23 was declared as the “National Space Day” because the Chandrayaan-3 mission accomplished safe and soft-landing of Vikram Lander on the lunar surface on August 23, 2023.

2. The theme for the year 2025 was “Aryabhatta to Gaganyaan: Ancient Wisdom to Infinite Possibilities”.

Which of the statements given above is/are correct?

(a) 1 only

(b) 2 only

(c) Both 1 and 2

(d) Neither 1 nor 2

Explanation

— India became the fourth country to land on the moon and the first to reach its southern polar region on August 23, 2023. To honour this landmark achievement, Hon’ble Prime Minister Shri Narendra Modi announced August 23 as “National Space Day”. Hence, statement 1 is correct.

— India is celebrating its second National Space Day [NSpD-2025] on August 23, 2025 with the theme “Aryabhatta to Gaganyaan: Ancient Wisdom to Infinite Possibilities”. Hence, statement 2 is correct.

— India’s National Space Day 2025 celebrates the enduring journey of exploration, innovation, and imagination from the profound astronomical insights of our ancient scholars to the cutting-edge frontiers of human spaceflight.

Therefore, option (c) is the correct answer.

(Other Source: http://www.isro.gov.in)

Previous Daily Subject-Wise-Quiz

Daily Subject-wise quiz — History, Culture, and Social Issues (Week 123)

Daily subject-wise quiz — Polity and Governance (Week 125)

Daily subject-wise quiz —  Science and Technology (Week 124)

Daily subject-wise quiz — Economy (Week 124)

Daily subject-wise quiz — Environment and Geography (Week 123)

Daily subject-wise quiz – International Relations (Week 124)

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