UPSC Prelims 2025
Science & Technology
Consider the following space missions:
I. Axiom-4
II. SpaDeX
III. Gaganyaan
How many of the space missions given above encourage and support micro-gravity research?
- A. Only one
- B. Only two
- C. All the three
- D. None
Explanation
Correct answer
C. All the three
✅ I. Axiom-4: Correct
Axiom-4 is a private crewed ISS mission focused on micro-gravity research through scientific experiments. ✅ II. SpaDeX: Correct
SpaDeX, ISRO’s autonomous docking tech demo, also supports micro-gravity research during its mission. ✅ III. Gaganyaan: Correct
India’s first human spaceflight, Gaganyaan, promotes micro-gravity research by enabling experiments in space. Therefore, all three missions support and encourage micro-gravity research.
Science & Technology
Current Affairs
Space Science & Exploration
UPSC Prelims 2015
Science & Technology
Indira Gandhi Peace Prize for Peace, Disarmament and Development for 2014, was given to which of the following?
- A. Bhabha Atomic Research Centre
- B. Indian Institute of Science
- C. Indian Space Research Organization
- D. Tata Institute of Fundamental Research
Explanation
Correct answer
C. Indian Space Research Organization
The Indira Gandhi Prize for Peace, Disarmament and Development for 2014 was presented to the Indian Space Research Organisation (ISRO). - It was awarded in recognition of its path-breaking achievements, especially the Mars Orbiter Mission; its significant contributions in strengthening international cooperation in the peaceful uses of outer space etc. - The award consists of a trophy made of banded Haematite Jasper, with a portrait of the late Prime Minister in the tradition of Jaipur miniature paintings, a cash award of Rs. 1 Crore and a Citation.
Science & Technology
Current Affairs
Space Science & Exploration
UPSC Prelims 2016
Science & Technology
Consider the following statements regarding: The Mangalyaan launched by ISRO
1. is also called the Mars Orbiter Mission
2. made India the second country to have a spacecraft orbit the Mars after USA
3. made India the only country to be successful in making its spacecraft orbit the Mars in its very first attempt
Which of the statements given above is/are correct?
- A. 1 only
- B. 2 and 3 only
- C. 1 and 3 only
- D. 1, 2 and 3
Explanation
Correct answer
C. 1 and 3 only
Statement 1 is correct: Mangalyaan is also called the Mars Orbiter Mission (MOM). This was its official designation. Statement 2 is incorrect: India was not the second country to orbit Mars. Several countries had successfully sent spacecraft to Mars before Mangalyaan, including the USA, Russia, and the European Space Agency (ESA). Statement 3 is correct: India was indeed the only country at that time to succeed in placing a spacecraft into Martian orbit on its very first attempt. This was a significant achievement for ISRO. Hence, option C is the correct answer.
Science & Technology
Space Science & Exploration
UPSC Prelims 2025
Science & Technology
GPS-Aided Geo Augmented Navigation (GAGAN) uses a system of ground stations to provide necessary augmentation. Which of the following statements is/are correct in respect of GAGAN?
I. It is designed to provide additional accuracy and integrity.
II. It will allow more uniform and high quality air traffic management.
III. It will provide benefits only in aviation but not in other modes of transportation.
Select the correct answer using the code given below.
- A. I, II and III
- B. II and III only
- C. I only
- D. I and II only
Explanation
Correct answer
D. I and II only
✅ Statement I: Correct
*GAGAN is an Indian SBAS developed by ISRO and AAI to enhance GPS accuracy and integrity, crucial for aviation safety.* ✅ Statement II: Correct
*It improves GPS reliability and accuracy, enabling better air traffic management and safer, efficient navigation.* ❌ Statement III: Incorrect
*GAGAN’s benefits extend beyond aviation to railways, roadways, maritime, agriculture, and disaster management.* Correct Answer: Only Statements I and II are correct.
Science & Technology
Space Science & Exploration
Emerging Information Technologies
UPSC Prelims 2022
Science & Technology
If a major solar storm (solar-flare) reaches the Earth, which of the following are the possible effects on the Earth?
1. GPS and navigation systems could fail.
2. Tsunamis could occur at equatorial regions.
3. Power grids could be damaged.
4. Intense auroras could occur over much of the Earth.
5. Forest fires could take place over much of the planet.
6. Orbits of the satellites could be disturbed.
7. Shortwave radio communication of the aircraft flying over polar regions could be interrupted.
Select the correct answer using the code given below:
- A. 1, 2, 4 and 5 only
- B. 2, 3, 5, 6 and 7 only
- C. 1, 3, 4, 6 and 7 only
- D. 1, 2, 3,4, 5, 6 and 7
Explanation
Correct answer
C. 1, 3, 4, 6 and 7 only
Out of the listed effects of a major solar storm, the most likely ones are Statement 1 is correct. A solar storm can disrupt the Earth's ionosphere, which can affect the signal transmission of GPS and other radio-based navigation systems. Statement 3 is correct. Strong currents induced by the solar storm in power grids can damage transformers and cause widespread blackouts. Statement 4 is correct. Solar storms can energize particles in the Earth's magnetosphere, leading to spectacular auroras at lower latitudes than usual. Statement 6 is correct. The drag from a solar storm can alter the orbits of satellites, especially those in lower Earth orbit. Statement 7 is correct. Similar to GPS, radio communication can be affected by disturbances in the ionosphere. Statement 2 is incorrect. Tsunamis are caused by underwater earthquakes or volcanic eruptions, not solar storms. Statement 5 is incorrect. While a solar storm could potentially ignite some fires through electrical sparks, this is not a widespread effect. Therefore, codes 2 and 5 should not form the part of answer.
Science & Technology
Space Science & Exploration
UPSC Prelims 2016
Science & Technology
With reference to ‘Astrosat’, the astronomical observatory launched by India, which of the following statements is/are correct?
1. Other than the USA and Russia, India is the only country to have launched a similar observatory into space.
2. Astrosat is a 2000 kg satellite placed in an orbit at 1650 km above the surface of the Earth.
- A. 1 only
- B. 2 Only
- C. Both 1 and 2
- D. Neither 1 nor 2
Explanation
Correct answer
D. Neither 1 nor 2
Statement 1 is incorrect: AstroSat is India's first dedicated multi-wavelength space observatory aimed at studying celestial sources in X-ray, optical and UV spectral bands simultaneously. India is the 5th country to join the space observatory elite list after the USA, Russia, Japan, and Europe. Statement 2 is incorrect: AstroSat with a lift-off mass of about 1513 kg was launched into a 650 km orbit inclined at an angle of 6 degrees to the equator by PSLV-C30. Therefore, option D is the correct answer.
Science & Technology
Space Science & Exploration
UPSC Prelims 2020
Science & Technology
“The experiment will employ a trio of spacecraft flying in formation in the shape of an equilateral triangle that has sides one million kilometres long, with lasers shining between the craft”. The experiment in question refers to
- A. Voyager
- B. New Horizons
- C. LISA Pathfinder
- D. Evolved LISA
Explanation
Correct answer
D. Evolved LISA
The description mentions three spacecraft in an equilateral triangle formation with million-kilometre sides using lasers for measurement.
This matches the design of the Evolved Laser Interferometer Space Antenna (eLISA) mission.
eLISA is a proposed space observatory aiming to detect gravitational waves using precisely positioned spacecraft. Voyager-2 and New Horizons are single spacecraft on exploration missions, not designed for gravitational wave detection. LISA Pathfinder was a precursor mission to test technologies for eLISA, not the full mission itself. Therefore, based on the details provided, the experiment refers to the Evolved LISA mission.
Science & Technology
Space Science & Exploration
Physics & Materials Science
UPSC Prelims 2014
Science & Technology
Which of the following pair is/are correctly matched?
|Spacecraft|Purpose|
|-- |--|
|1. Cassini-Huygens | Orbiting Venus and transmitting data to the Earth|
|2. Messenger|Mapping and investigating the Mercury|
|3. Voyager 1 and 2 | Exploring the outer solar system|
Select the correct answer using the code given below.
- A. 1 only
- B. 2 and 3 only
- C. 1 and 3 only
- D. 1, 2 and 3
Explanation
Correct answer
B. 2 and 3 only
Pair 1 is incorrectly matched: The Cassini-Huygens mission was a joint NASA/ESA/ASI mission to study the planet Saturn and its system of rings and moons. The Huygens probe successfully landed on Saturn's largest moon, Titan. Pair 2 is correctly matched: The MESSENGER (MErcury Surface, Space ENvironment, GEochemistry, and Ranging) was a NASA spacecraft that orbited the planet Mercury from 2011 to 2015, studying its chemical composition, geology, and magnetic field. Pair 3 is correctly matched: These twin NASA spacecraft were launched in 1977 to conduct a "Grand Tour" of the outer planets. They provided detailed images and data on Jupiter, Saturn, Uranus, and Neptune and are now continuing their journey into interstellar space.
Science & Technology
Space Science & Exploration
UPSC Prelims 2024
Science & Technology
With reference to radioisotope thermoelectric generators (RTGs), consider the following statements:
1. RTGs are miniature fission reactors.
2. RTGs are used for powering the onboard systems of spacecrafts.
3. RTGs can use Plutonium-238, which is a by-product of weapons development.
Which of the statements given above are correct?
- A. 1 and 2 only
- B. 2 and 3 only
- C. 1 and 3 only
- D. 1, 2 and 3
Explanation
Correct answer
B. 2 and 3 only
* Statement 1: Incorrect. RTGs (Radioisotope Thermoelectric Generators) are not miniature fission reactors. Fission reactors use nuclear fission, a process of splitting atoms to release a tremendous amount of energy. RTGs, on the other hand, utilize the natural radioactive decay of isotopes to generate heat, which is then converted to electricity through a process called thermoelectricity. * Statement 2: Correct. RTGs are indeed a reliable power source for spacecraft, especially those venturing far from the sun where solar panels become ineffective. They provide consistent, low-level electric power for extended periods, making them ideal for probes, satellites, and rovers in deep space. * Statement 3: Correct. Plutonium-238 is a common isotope used in RTGs due to its long half-life (the time it takes for half of the material to decay) and its ability to generate a steady heat output from its decay process. While it can be a byproduct of weapons development, there are also alternative ways to produce Plutonium-238 specifically for peaceful applications like RTGs.
Science & Technology
Space Science & Exploration
Physics & Materials Science
UPSC Prelims 2018
Science & Technology
With reference to India’s satellite launch vehicles, consider the following statements:
1. PSLVs launch the satellites useful for Earth resources monitoring whereas GSLVs are designed mainly to launch communication satellites.
2. Satellites launched by PSLV appear to remain permanently fixed in the same position in the sky, as viewed from a particular location on Earth.
3. GSLV Mk III is a four-stage launch vehicle with the first and third stages using solid rocket motors, and the second and fourth stages using liquid rocket engines.
Which of the statements given above is/are correct?
- A. 1 only
- B. 2 and 3
- C. 1 and 2
- D. 3 only
Explanation
Statement 1 is correct. PSLV (Polar Satellite Launch Vehicle) is primarily used to launch Earth observation/monitoring satellites, while GSLV (Geosynchronous Satellite Launch Vehicle) is designed to launch communication satellites into geosynchronous transfer orbits. Statement 2 is incorrect. Satellites launched by PSLV are typically placed in polar or sun-synchronous orbits, which are not geosynchronous. These satellites appear to move across the sky as viewed from a particular location on Earth. Statement 3 is incorrect. The GSLV Mk III is a three-stage launch vehicle, not a four-stage one. The first stage uses solid rocket motors, the second stage uses liquid rocket engines, and the third stage uses a cryogenic rocket engine.
Science & Technology
Space Science & Exploration