The Indian National Committee for Space Research (INCOSPAR) was set up in 1962, An indigenous series of sounding rockets named Rohini was subsequently developed and started undergoing launches from 1967 onwards. Under the government of Indira Gandhi, INCOSPAR was superseded by ISRO. Later in 1972, a space commission and Department of Space (DoS) were set up to oversee space technology development in India specifically. ISRO was brought under DoS, institutionalising space research in India and forging the Indian space programme into its existing form. India joined the Soviet Interkosmos programme for space cooperation and got its first satellite Aryabhatta in orbit through a Soviet rocket.
SLV
Efforts to develop an orbital launch vehicle began after mastering sounding rocket technology. The concept was to develop a launcher capable of providing sufficient velocity for a small mass to enter low Earth orbit. The Satellite Launch Vehicle or SLV was a small-lift launch vehicle project started in 1973 to develop the technology needed to launch satellites. SLV was intended to reach a height of 400 kilometres (250 mi) and carry a payload of 40 kg (88 lb). It took 7 years for ISRO to develop the SLV. A Launch Pad, ground stations, tracking networks, radars and other communications were set up for a launch campaign.
The SLV’s first launch in August 1979 carried a Rohini technology payload but could not inject the satellite into its desired orbit. It was followed by a successful launch in 1980 carrying a Rohini Series-I satellite. RS-1 was the third Indian satellite to reach orbit as Bhaskara had been launched from the USSR in 1979. The SLV-3 later had two more launches before discontinuation in 1983.
ASLV
ISRO’s Liquid Propulsion Systems Centre (LPSC) was set up in 1985 and started working on a more powerful engine, Vikas, based upon the French Viking. Two years later, facilities to test liquid-fuelled rocket engines were established and development and testing of various rocket engines thrusters began. At the same time, another solid-fuelled rocket Augmented Satellite Launch Vehicle was being developed, and technologies to launch satellites into geostationary orbit (GTO).
The ASLV was a five-stage vehicle. Two strap-on boosters acted as a first stage, with the core stage igniting after booster burn out. The payload capacity of the ASLV was approximately 150 kg (330 lb) to an orbit of 400 km (250 mi) with a 47-degree inclination.The height to diameter ratio of ASLV was very large which resulted in the vehicle being unstable in flight. This was compounded by the fact that many of the critical events during a launch like the core ignition and the booster separation happened at the Tropopause where the dynamic loads on the launcher was at the maximum.
The ASLV made four launches, of which one was successful, two failed to achieve orbit, and a third achieved a lower than planned orbit which decayed quickly. The type made its maiden flight on 24 March 1987, and its final flight on 4 May 1994.ISRO did not have sufficient funds for both the Polar Satellite Launch Vehicle programme and the ASLV programme at the same time and the ASLV programme was terminated after the initial developmental flights.
PSLV
Polar Satellite Launch Vehicle or PSLV was the first medium-lift launch vehicle from India which enabled India to launch all its remote-sensing satellites into Sun-synchronous orbit. Development began as early as 1978 and among 35 proposed configurations, four were picked. Funding was approved in July 1982 for the finalised design:- a single large solid core as first stage with six strap-ons derived from the SLV first stage, a liquid fuelled second stage, and two solid upper stages. This configuration later was undated with a liquid fuelled upper stage.
The PSLV was first launched on 20 September 1993. The first and second stages performed as expected, but an attitude control problem led to the collision of the second and third stages at separation, and the payload failed to reach orbit. With the exception of its maiden flight and two partial failures later, PSLV has had a streak of more than 50 successful flights. PSLV has enabled India to launch all of its low Earth orbit satellites, small payloads to GTO and hundreds of foreign satellites.
GSLV Mk. I
The conceptualisation and planning phases for what would become the GSLV Mk. I started around 1986. This period marked the initiation of efforts to design a launch vehicle capable of placing heavier payloads into geostationary transfer orbits (GTO), addressing India’s growing need for self-reliance in satellite launches. The formal agreement with Russia for the supply and technology transfer of the KVD-1 cryogenic engine, which would later be integral to the GSLV Mk. I, was signed in 1991, further advancing the program’s development.
The first successful launch of GSLV Mk. I occurred on April 18, 2001, with subsequent flights demonstrating both successes and challenges. Notably, the GSLV-D2 mission in 2003 successfully placed the GSAT-2 satellite into orbit, marking a significant achievement for the program.
GSLV Mk. II
With the collapse of the Soviet Union and geopolitical constraints and technology embargoes hindering India’s access to foreign cryogenic technology the ISRO initiated efforts to develop its own cryogenic technology.Throughout the mid to late 1990s, ISRO focused on mastering the complexities of cryogenic propellants and precision engineering. Extensive testing of individual components and integrated systems was conducted, culminating in rigorous qualification tests by the early 2000s.
The first flight test of the GSLV Mk. II including the ISRO designed and built Cryogenic Upper Stage (CUS) occurred on 15 April 2010. It failed to reach orbit due to malfunction of the Fuel Booster Turbo Pump (FBTP), Despite the setback ISRO persisted and refined the technology. The breakthrough came on January 5, 2014, when the CE-7.5 successfully powered the GSLV-D5 mission, launching the GSAT-14 satellite into orbit. This success marked India’s self-reliance in cryogenic rocket technology and significantly enhanced the capabilities of the GSLV, positioning India as a formidable player in the global space industry.
GSLV Mk. III (LVM3)
Development of the GSLV Mk. III (LVM3) began in the early 2000s, with the first launch planned for 2009–2010. The unsuccessful launch of GSLV Mk. II, due to failure in the cryogenic upper stage, delayed the LVM3 development program. The LVM3, while sharing a name with the GSLV, features different systems and components.
It features a more powerful configuration than its predecessors, including two large solid rocket boosters, a liquid core stage powered by two Vikas engines, and an advanced cryogenic upper stage using the CE-20 engine. The GSLV Mk. III’s development was driven by the need for a vehicle that could meet India’s growing demands for communication satellites and interplanetary missions.
The GSLV Mk III’s first successful flight, designated LVM3-X/CARE, took place on December 18, 2014, with a suborbital test to validate the vehicle’s design and performance. The first operational flight occurred on June 5, 2017, successfully deploying the GSAT-19 satellite into orbit. This marked a new era for ISRO, demonstrating its capability to independently launch heavy payloads. The GSLV Mk. III also played a crucial role in launching the Chandrayaan-2 mission to the Moon in 2019, further showcasing its versatility and reliability for diverse mission profiles.
SSLV
In 2015, a National Institute of Advanced Studies report proposed development path of a ‘Small Satellite launch Vehicle’ to launch strategic payloads at a drastically reduced price and higher launch rate compared to Polar Satellite Launch Vehicle (PSLV). The Design of the vehicle was completed by December 2018 and Assembly was completed by December 2020.
The first static fire test was conducted on 18 March 2021 however it was unsuccessful. About 60 seconds into the test, oscillations were observed and after 95 seconds, the nozzle of SS1 stage disintegrated. The second static fire test of SSLV first stage SS1 was conducted on 14 March 2022 at SDSC-SHAR and met the required test objectives.
The first developmental flight of the SSLV occurred on 7 August 2022, however due to Software errors it was a failure. It subsequently launched successfully on 10 February 2023 deploying three satellites.
Lunar exploration
Chandryaan (lit. ’Mooncraft’) are India’s series of lunar exploration spacecraft. The initial mission included an orbiter and controlled impact probe while later missions include landers, rovers and sampling missions.
Chandrayaan-1 was India’s first mission to the Moon. The robotic lunar exploration mission included a lunar orbiter and an impactor called the Moon Impact Probe. ISRO launched it using a modified version of the PSLV on 22 October 2008 from Satish Dhawan Space Centre. It entered lunar orbit on 8 November 2008, carrying high-resolution remote sensing equipment for visible, near infrared, and soft and hard X-ray frequencies. During its 312-day operational period (two years were planned), it surveyed the lunar surface to produce a complete map of its chemical characteristics and three-dimensional topography. The polar regions were of special interest, as they had possible ice deposits.
Chandrayaan-2 was the second mission to the Moon. It was launched on a Geosynchronous Satellite Launch Vehicle Mark III (GSLV Mk III) on 22 July 2019, consisting of a lunar orbiter, the Vikram lander, and the Pragyan lunar rover, all developed in India. It was the first mission meant to explore the little-explored lunar south pole region. The objective of the Chandrayaan-2 mission was to land a robotic rover to conduct various studies on the lunar surface. However, the lander deviated from its intended trajectory starting from an altitude of 2.1 km (1.3 mi), and telemetry was lost seconds before touchdown was expected. A review board concluded that the crash-landing was caused by a software glitch.The lunar orbiter was efficiently positioned in an optimal lunar orbit, extending its expected service time from one year to seven.
Chandryaan-3 was India’s second attempt to soft-land on the Moon after the partial failure of Chandrayaan-2. The mission would only include a lander-rover set and would communicate with the orbiter from the previous mission. On 23 August 2023, ISRO became the first space agency to successfully land a spacecraft on the lunar south pole region, and only the fourth space agency ever to land on the Moon.
Mars exploration
The Mars Orbiter Mission (MOM), informally known as Mangalyaan (eng: ”MarsCraft” ) was launched into Earth orbit on 5 November 2013 by the Indian Space Research Organisation (ISRO) and entered Mars orbit on 24 September 2014.India thus became the first country to have a space probe enter Mars orbit on its first attempt.
The data collected by Mangalyaan has been crucial in complementing the findings of other Mars missions. The mission’s findings have provided valuable insights into the presence of methane, surface processes, atmospheric composition, and mineralogy. Mangalyaan’s contributions are significant for comparative planetology and enhance our understanding of Mars as a potentially habitable planet in the past.