Q10. Oceansat-2 helps India with which activities?
1. Estimating atmospheric water-vapour content
2. Studying and forecasting monsoon-related processes
3. Assessing coastal water quality.
[UPSC CSE Prelims 2010]
(A) 1 and 2 only
(B) 2 only
(C) 1 and 3 only
(D) 1, 2 and 3
Answer: (D) 1, 2 and 3
Explanation: Oceansat-2 carried instruments for monitoring ocean colour and surface winds, which support atmospheric and monsoon studies as well as assessments of coastal-water conditions. Satellite data are combined with observations and models for operational environmental applications.
Q9. What is Bhuvan in the context of Indian space technology?
[UPSC CSE Prelims 2010]
(A) A distance-education minisatellite
(B) A Moon impact probe
(C) ISRO’s geospatial portal with two-dimensional and three-dimensional views
(D) An Indian optical space telescope
Answer: (C) ISRO’s geospatial portal with two-dimensional and three-dimensional views
Explanation: Bhuvan is ISRO’s web-based geospatial platform for displaying and analysing Indian Earth-observation datasets. It provides imagery, mapping layers and 2D or 3D visualisation for uses such as planning, natural-resource management and disaster-related mapping.
Q8. Which country launched the SELENE-1 lunar orbiter, also called Kaguya?
[UPSC CSE Prelims 2008]
(A) China
(B) European Union
(C) Japan
(D) United States
Answer: (C) Japan
Explanation: Japan’s space agency JAXA launched the SELENE mission, better known as Kaguya, in 2007. It used multiple instruments to study lunar geology, topography, gravity and other properties, contributing to understanding the Moon’s origin and evolution.
Q7. Where is the Indian rocket-engine test facility used for a 2007 cryogenic-engine test located?
[UPSC CSE Prelims 2008]
(A) Balasore
(B) Thiruvananthapuram
(C) Mahendragiri
(D) Karwar
Answer: (C) Mahendragiri
Explanation: Mahendragiri in Tamil Nadu hosts major ISRO propulsion-test facilities, formerly associated with the Liquid Propulsion Systems Centre and now the ISRO Propulsion Complex. Cryogenic rocket engines use very cold liquid propellants and require specialised testing infrastructure.
Q6. Which of these is the NASA spacecraft that explored Saturn with the Huygens probe?
[UPSC CSE Prelims 2008]
(A) Apophis
(B) Cassini
(C) Spitzer
(D) TechSAR
Answer: (B) Cassini
Explanation: Cassini was a planetary exploration spacecraft studying Saturn and its moons. Apophis is an asteroid, Spitzer was an infrared observatory and TechSAR an Earth-observation satellite. Huygens separated from Cassini and landed on Saturn’s moon Titan.
Q5. Which comet nucleus was struck and examined by NASA’s Deep Impact mission?
[UPSC CSE Prelims 2007]
(A) Halley
(B) Hale-Bopp
(C) Hyakutake
(D) Tempel 1
Answer: (D) Tempel 1
Explanation: NASA’s Deep Impact spacecraft released a projectile that collided with comet Tempel 1 in July 2005. The resulting debris plume gave scientists clues about the comet’s internal material, helping research into primitive Solar System substances.
Q4. Which pairing is incorrect?
[UPSC CSE Prelims 2007]
(A) COBE — satellite programme
(B) FALCON — undersea cable system
(C) Discovery — space shuttle
(D) Atlantis — space station
Answer: (D) Atlantis — space station
Explanation: Atlantis was a NASA Space Shuttle orbiter, not a permanent space station. Discovery was another shuttle, while COBE examined cosmic microwave background radiation. FALCON refers to a submarine telecommunications cable system rather than an orbiting spacecraft.
Q3. Consider:
1. India launched METSAT, its first dedicated meteorological satellite, in September 2002.
2. PSLV-C4 placed a payload exceeding 1,000 kg into geosynchronous transfer orbit.
Which are correct?
[UPSC CSE Prelims 2003]
(A) 1 only
(B) 2 only
(C) Both 1 and 2
(D) Neither 1 nor 2
Answer: (C) Both 1 and 2
Explanation: PSLV-C4 launched METSAT, later renamed Kalpana-1, in September 2002. This spacecraft advanced India’s dedicated meteorological observation capability. Its launch also demonstrated PSLV’s ability to place a payload exceeding one tonne into geosynchronous transfer orbit.
Q2. Which statements about Indian satellites are correct?
1. All INSAT-series satellites had been launched abroad.
2. PSLV launched IRS-series satellites.
3. India had already used an indigenous cryogenic GSLV upper stage.
4. GSAT launched in 2001 carried digital broadcasting and internet-service demonstration payloads.
[UPSC CSE Prelims 2002]
(A) 1, 2, 3 and 4
(B) 2, 3 and 4 only
(C) 1, 2 and 4 only
(D) 1 and 3 only
Answer: (C) 1, 2 and 4 only
Explanation: At the time of this question, INSAT launches used foreign vehicles and PSLV served the Indian Remote Sensing series. Early GSLV cryogenic stages were not indigenous; GSAT-1 was a 2001 technology demonstrator. Hence statements 1, 2 and 4 apply.
Q1. Assertion: Artificial satellites are always launched from Earth eastward.
Reason: Earth rotates west to east and therefore supplies the satellite with escape velocity.
[UPSC CSE Prelims 2002]
(A) Both statements true; reason explains assertion
(B) Both true; reason does not explain assertion
(C) Assertion true; reason false
(D) Assertion false; reason true
Answer: (C) Assertion true; reason false
Explanation: The examination’s keyed response was C. Eastward launches gain speed from Earth’s rotation, reducing the propellant required for many prograde orbits. This boost does not automatically provide escape velocity. In modern terminology, the word “always” is overly absolute.
