ISRO, India’s pride
The Indian Space Research Organisation (ISRO)) is the space agency of the Government of India headquartered in the city of Bengaluru. Its vision is to “harness space technology for national development while pursuing space science research and planetary exploration.” Indian National Committee for Space Research (INCOSPAR) was established by Jawaharlal Nehru, the first Prime Minister of the Indian Government under the DAE in 1962, with the urging of scientist Vikram Sarabhai recognizing the need in space research. INCOSPAR grew into ISRO in 1969 also under the DAE.In 1972 Government of India setup a Space Commission and the Department of Space (DOS), bringing ISRO under the DOS. The establishment of ISRO thus institutionalized space research activities in India. It is managed by the Department of Space, which reports to the Prime Minister of India.
India’s first satellite Aryabhata was launched by the Soviet Union on 19 April 1975 from Kapustin Yar using a Kosmos-3M launch vehicle. (It was built by the ISRO) to gain experience in building and operating a satellite in space. India has launched 100 Indian satellites of many types as on 31 January 2018. Satellites have been launched from various vehicles, including those launched by Russian, European and American rockets, as well as those launched indigenously by India. The organisation responsible for India’s satellite program is the Indian Space Research Organisation (ISRO).
ISRO also launches satellites for foreign countries. As of November 2018, ISRO has launched 239 satellites for 28 foreign countries. In January 2017, India launched 104 satellites in a single mission, out of which 96 were from the United States and the rest from the Netherlands, Kazakhstan, Israel, UAE and India, by using a single launch vehicle. This eclipsed the previous record of 37 held by Russia.
ISRO Missions in 2018
GSLV-F11 / GSAT-7A Mission- GSLV-F11 successfully launched GSAT-7A, ISRO’s 39th communication satellite, on December 19, 2018 at 1610 hrs (IST) from the Second Launch Pad (SLP) of Satish Dhawan Space Centre SHAR, Sriharikota.
GSLV-F11-GSLV-F11 is the 13th flight of India’s Geosynchronous Satellite Launch Vehicle (GSLV) and its 7th flight with indigenous Cryogenic Upper Stage (CUS).
GSLV – F11- GSLV – F11 is ISRO’s fourth generation launch vehicle with three stages. The four liquid strap-ons and a solid rocket motor at the core form the first stage. The second stage of the vehicle is equipped with high thrust engine using liquid fuel. The Cryogenic Upper Stage forms the third and final stage of the vehicle.
GSAT-7A – GSAT-7A with a lift-off mass of 2250 kg, is a geostationary satellite carrying communication transponders in Ku-band. The Satellite is built to provide communication capability to the users over the Indian region.
GSAT-11 Mission-India’s next generation high throughput communication satellite, GSAT-11 was successfully launched on December 05, 2018 from Kourou launch base, French Guiana by Ariane-5 VA-246. Weighing about 5854 kg, GSAT-11 is the heaviest satellite built by ISRO.
GSAT-11 is the fore-runner in the series of advanced communication satellites with multi-spot beam antenna coverage over Indian mainland and Islands. GSAT-11 will play a vital role in providing broadband services across the country. It will also provide a platform to demonstrate new generation applications. GSAT-11 was launched into a Geosynchronous Transfer Orbit and subsequently ISRO’s Master Control Facility at Hassan taken over the control of GSAT-11 to perform the initial orbit raising maneuvers using the Liquid Apogee Motor of the satellite for placing it in circular Geostationary Orbit
PSLV-C43 successfully places HysIS- On November 29, 2018 the Indian Space Research Organisation’s (ISRO) workhorse, the PSLV, carrying 31 satellites, soared in a trajectory crossing the path of the Sun and sped to inject the country’s Hyper Spectral Imaging Satellite (HysIS), dubbed ‘Sharp Eye’, in its intended orbit. The PSLV C-43 inserted 30 small commercial satellites from various countries into the orbits requested by the customers. The HysIS is is an Earth observation satellite primarily to assist in a wide range of applications in agriculture, forestry, geological environments, coastal zones, among others. The 30 satellites are one each from Australia, Canada, Colombia, Finland, Malaysia, Netherlands and Spain, and 23 from the USA.
GSAT-29- GSAT-29 satellite with a lift-off mass of 3423 kg, is a multi-beam, multiband communication satellite of India, configured around the ISRO’s enhanced I-3K bus. This is the heaviest satellite launched from India. GSAT-29 carries Ka/Ku-band high throughput communication transponders which will bridge the digital divide of users including those in Jammu & Kashmir and North Eastern regions of India. It also carries Q/V-band payload, configured for technology demonstration at higher frequency bands and Geo-stationary High Resolution Camera. carried onboard GSAT-29 spacecraft. An optical communication payload, for the first time, will be utilized for data transmission.
EMISAT- EMISAT is a satellite built around ISRO’s Mini Satellite-2 bus weighing about 436 kg. The satellite was successfully placed in its intended sun-synchronous polar orbit of 748 km height by PSLV-C45 on April 01, 2019. The satellite is intended for electromagnetic spectrum measurement.India’s PSLV-C45 successfully injected EMISAT and 28 international customer satellites into their designated orbits. The PSLV-C45 lifted off at 09:27 Hrs (IST) on April 01, 2019 from the second launch pad of Satish Dhawan Space Centre SHAR, Sriharikota in its 47th flight. This flight marked the first mission of PSLV-QL, a new variant of PSLV with four strap-on motors.
Some Important Missions of ISRO in past
Chandrayaan-1 was India’s first lunar probe. It was launched by the Indian Space Research Organisations in October 2008, and operated until August 2009. The mission included a lunar orbiter and an impactor. The mission was a major boost to India’s space program, as India researched and developed its own technology in order to explore the Moon. The vehicle was successfully inserted into lunar orbit on 8 November 2008.
Mars Mission (MOM), also called Mangalyaan is a spacecraft orbiting Mars since 24 September 2014. It was launched on 5 November 2013 by the Indian Space Research Organisation (ISRO). It is India’s first interplanetary mission and ISRO has become the fourth space agency to reach Mars, after the Soviet space program, NASA, and the European Space Agency. It is the first Asian nation to reach Mars orbit, and the first nation in the world to do so in its first attempt.
ASTROSAT is the first dedicated Indian Astronomy satellite mission launched by ISRO on 28 September 2015, which will be helpful in enable multi-wavelength observations of the celestial bodies and cosmic sources in X-ray and UV spectral bands simultaneously. The scientific payloads cover the Visible (3500–6000 Å…), UV (1300–op Å…), soft and hard X-ray regimes (0.5–8 keV; 3–80 keV). The uniqueness of ASTROSAT lie in its wide spectral coverage extending over visible, UV, soft and hard X-ray regions.
South Asia Satellite was launched on 5 May 2017.This is a satellite which has been developed by ISRO for South Asian Nations. Indian Prime Minister Narendra Modi announced this in November 2014 during the 18th SAARC session.
Chandrayaan-2 is India’s second lunar exploration mission after Chandrayaan-1. Developed by the Indian Space Research Organisation (ISRO), the mission is planned to be launched to the Moon by a Geosynchronous Satellite Launch Vehicle Mark III (GSLV Mk III). Chandrayaan-2 launch is tentatively scheduled between 9 to 16 July 2019, with landing expected on 6 September 2019. It includes a lunar orbiter, lander and rover, all developed indigenously. Chandrayaan-2 will attempt to soft land a lander and rover in a high plain between two craters, Manzinus C and Simpelius N, at a latitude of about 70° south. If successful, Chandrayaan-2 will be the first mission to land a rover near the lunar south pole According to ISRO, this mission will use and test various new technologies and conduct new experiments. The wheeled rover will move on the lunar surface and will perform on-site chemical analysis. The data will be relayed to Earth through the Chandrayaan-2 orbiter, which will piggyback on the same launch. Chandrayaan-2 will make India the 4th country in the world to soft-land on the moon, a feat achieved only by US, USSR and China till now.
Gaganyaan (“Orbital Vehicle”) is an Indian crewed orbital spacecraft intended to be the basis of the Indian Human Spaceflight Programme. The spacecraft is being designed to carry three people, and a planned upgraded version will be equipped with rendezvous and docking capability. In its maiden crewed mission, Indian Space Research Organisation’s largely autonomous 3.7-tonne capsule will orbit the Earth at 400 km (250 mi) altitude for up to seven days with a three-person crew on board. The crewed vehicle is planned to be launched on ISRO’s GSLV Mk III in December 2021. This HAL-manufactured crew module had its first un-crewed experimental flight on 18 December 2014. As of May 2019, design of crew module has been completed.[
ISRO’S 7 Expeditions Including Venus
Six years after landing on Mars, ISRO has decided to step on Venus on 2023. Venus and Earth share similarities in mass, size, composition, density and gravity. K Sivan, Chairman of ISRO, reported that the agency is working on 7 interplanetary missions for the next decade. The whole set include:
- Exposat Planetary exploration, to study cosmic radiations in 2020
- Aditya L1, to the sun in 2021
- Mars Orbiter Mission -2 IN 2022
- Mission to Venus in 2023
- Chandrayan 3 or Luner Polar Exploration, in 2024
- Exoworlds, an exploration outside the solar system in 2028
Understanding PSLV and GSLV
Both PSLV (Polar Satellite Launch Vehicle) and GSLV (Geosynchronous Satellite Launch Vehicle) are the satellite-launch vehicles (rockets) developed by ISRO. PSLV is designed mainly to deliver the “earth-observation” or “remote-sensing” satellites with lift-off mass of up to about 1750 Kg to Sun-Synchronous circular polar orbits of 600-900 Km altitude.
The remote sensing satellites orbit the earth from pole-to-pole (at about 98 deg orbital-plane inclination). An orbit is called sun-synchronous when the angle between the line joining the centre of the Earth and the satellite and the Sun is constant throughout the orbit.
Due to their sun-synchronism nature, these orbits are also referred to as “Low Earth Orbit (LEO)” which enables the on-board camera to take images of the earth under the same sun-illumination conditions during each of the repeated visits, the satellite makes over the same area on ground thus making the satellite useful for earth resources monitoring.
Apart from launching the remote sensing satellites to Sun-synchronous polar orbits, the PSLV is also used to launch the satellites of lower lift-off mass of up to about 1400 Kg to the elliptical Geosynchronous Transfer Orbit (GTO).
PSLV is a four-staged launch vehicle with first and third stage using solid rocket motors and second and fourth stages using liquid rocket engines. It also uses strap-on motors to augment the thrust provided by the first stage, and depending on the number of these strap-on boosters, the PSLV is classified into its various versions like core-alone version (PSLV-CA), PSLV-G or PSLV-XL variants.
The GSLV is designed mainly to deliver the communication-satellites to the highly elliptical (typically 250 x 36000 Km) Geosynchronous Transfer Orbit (GTO). The satellite in GTO is further raised to its final destination, viz., Geo-synchronous Earth orbit (GEO) of about 36000 Km altitude (and zero deg inclination on equatorial plane) by firing its in-built on-board engines.
Due to their geo-synchronous nature, the satellites in these orbits appear to remain permanently fixed in the same position in the sky, as viewed from a particular location on Earth, thus avoiding the need of a tracking ground antenna and hence are useful for the communication applications.
Two versions of the GSLV are being developed by ISRO. The first version, GSLV Mk-II, has the capability to launch satellites of lift-off mass of up to 2,500 kg to the GTO and satellites of up to 5,000 kg lift-off mass to the LEO. GSLV MK-II is a three-staged vehicle with first stage using solid rocket motor, second stage using Liquid fuel and the third stage, called Cryogenic Upper Stage, using cryogenic engine.