Space Technology
Subject: General Science — Technology & Environment | Topic: Space Technology Exam: AP Group 2 (APPSC) | Sources: ISRO official, NCERT, Lucent's GS
Introduction
Space technology is a high-yield topic for APPSC, especially given Sriharikota's location in Andhra Pradesh. Expect 2-3 questions on ISRO missions, launch vehicles, and landmark achievements. Chandrayaan-3, Gaganyaan, and Aditya-L1 are hot topics for upcoming exams.
Indian Space Programme — History
- Father of Indian Space Programme: Dr. Vikram Sarabhai.
- ISRO: Established 15 August 1969. HQ: Bengaluru.
- Sriharikota (SDSC-SHAR): India's primary launch centre in Nellore district, Andhra Pradesh. Named after ISRO's second chairman Satish Dhawan.
- First rocket launch: Thumba, Kerala, 21 Nov 1963 (sounding rocket).
- Aryabhata (1975): India's first satellite (launched by Soviet rocket).
- SLV-3 (1980): First indigenous launch vehicle. Project Director: Dr. APJ Abdul Kalam. Made India 7th country with independent launch capability.
Launch Vehicles
| Vehicle | Capability | Key Facts |
|---|---|---|
| PSLV | ~1,750 kg to SSO | ISRO's workhorse; 63 launches; 92% success; 104 satellites in one mission (world record, 2017) |
| GSLV Mk II | ~2,250 kg to GTO | Uses indigenous cryogenic upper stage |
| LVM3 (formerly GSLV Mk III) | 4,000 kg GTO / 8,000 kg LEO | India's heaviest; used for Chandrayaan-2/3 |
| SSLV | Up to 500 kg to LEO | Small, low-cost, quick-turnaround |
Satellite Systems
| System | Purpose |
|---|---|
| INSAT | Communication, broadcasting, meteorology (since 1983) |
| IRS/EOS | Remote sensing — largest constellation in the world |
| NavIC (IRNSS) | India's regional navigation (7 satellites, <20m accuracy over India) |
| GSAT series | Communication; GSAT-7/7A for Navy/Air Force |
Landmark Missions
| Mission | Year | Achievement |
|---|---|---|
| Chandrayaan-1 | 2008 | First lunar mission; detected water on Moon; 4th country to reach Moon |
| Mangalyaan (MOM) | 2013-14 | First Mars mission; success on first attempt (no other country/agency achieved this); cost ~₹450 crore |
| Chandrayaan-2 | 2019 | Lander crashed; orbiter still operational |
| Chandrayaan-3 | 2023 | Successful soft landing near lunar south pole (23 Aug 2023); India = 4th country to soft-land; first at south pole. 23 Aug = National Space Day |
| Aditya-L1 | 2023 | First solar observatory; at Sun-Earth L1 point (~1.5 million km); India = 5th entity at L1 |
| NISAR | Jul 2025 | Joint NASA-ISRO; Earth surface change studies; dual-frequency radar |
Gaganyaan Programme
- India's first human spaceflight programme.
- Goal: 3 astronauts (Gaganauts) to ~400 km LEO for 3 days.
- HLVM3 (Human-rated LVM3) launch vehicle.
- IADT-01 (Aug 2025): successful air drop test of 4.8-tonne capsule.
- If successful: India becomes 4th nation to independently send humans to space (after Russia, USA, China).
Space Concepts
| Concept | Details |
|---|---|
| LEO | 160-2000 km (ISS, remote sensing) |
| GEO | 35,786 km; appears stationary; 24-hour period (communication) |
| SSO | Passes same point at same local time (remote sensing) |
| Escape velocity | 11.2 km/s (Earth) |
| Lagrange Points | 5 points where Sun-Earth gravity balances. L1: Aditya. L2: James Webb |
| Cryogenic engine | Liquid H₂ + liquid O₂; highest efficiency |
Global Space Landmarks
| Event | Year | Details |
|---|---|---|
| Sputnik 1 | 1957 | First satellite (USSR) |
| Yuri Gagarin | 1961 | First human in space (Vostok 1) |
| Neil Armstrong | 1969 | First human on Moon (Apollo 11) |
| Rakesh Sharma | 1984 | First Indian in space ("Saare Jahan Se Achha") |
| Kalpana Chawla | 1997 | First Indian-born woman in space |
AP-Specific Facts
- Sriharikota is in Nellore district, AP — India's only operational launch centre.
- Barrier island between Pulicat Lake and Bay of Bengal.
- Two launch pads. East coast ideal for polar and equatorial orbits.
Likely Exam Questions
-
India's first satellite was: Ans: Aryabhata (1975)
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Chandrayaan-3 made India the ___ country to soft-land on the Moon: Ans: 4th (and first near the south pole)
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Sriharikota is located in which district? Ans: Nellore district, Andhra Pradesh
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ISRO's Mars Orbiter Mission cost approximately: Ans: ₹450 crore (~$74 million)
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The Gaganyaan programme aims to make India the ___ nation to send humans to space: Ans: 4th
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NavIC provides positioning accuracy of better than: Ans: 20 metres over India
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Aditya-L1 is placed at which Lagrange point? Ans: L1 (Sun-Earth)
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The first Indian in space was: Ans: Rakesh Sharma (1984)
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PSLV set a world record by launching how many satellites in one mission? Ans: 104 satellites (PSLV-C37, February 2017)
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National Space Day is celebrated on: Ans: 23 August (Chandrayaan-3 landing date)