Aditya MadanapalleDec 29, 2017 14:38:09 IST
In 2017, ISRO accomplished the impressive feat of launching a very large number of very small satellites, indefinitely extended the life of its Mars mission, laid the groundwork for its future "workhorse" rocket and contributed resources for studying an explosive event that unleashed 10,000 Earth masses of gold into the infinite blackness of space.
ISRO’s launch vehicles continued to shatter records
ISRO’s “workhorse”, the Polar Satellite Launch Vehicle (PSLV), started the year on a high note with the record breaking deployment of 104 satellites with a single rocket in February 2017. The primary payload was the CartoSat-2D, the fifth earth observation satellite in the CartoSat series. Co-passengers on the mission were two nanosatellites from India, a flock of 88 Doves by Planet and a number of academic satellites.
Celebratory messages poured in from all sides, including a National Daily in China, which praised ISRO for proving the need for smaller launch vehicles to economically deploy smaller satellites. Space scientist G Madhavan Nair upped the ante by proclaiming that ISRO used reliable technologies for the launch and that the Indian Space Agency had the capacity to even launch 400 nanosatellites in one go.
While ISRO was widely praised for launching so many satellites at once, ISRO was not going out to break any records and actually pointed out that the number was only incidental. The feat of packing 104 satellites into a single launch vehicle was made possible because of the smaller satellites of the CubeSat standard and ISRO’s own modular bus system for small satellites, the ISRO Nano Satellite (INS). In the run up to the launch, ISRO Chairman AS Kiran Kumar had told reporters, “We are not looking at it as a record or anything. We are just trying to maximise our capability with each launch and trying to utilise that launch for the ability it has got and get the maximum in return.”
ISRO had to use a number of innovative approaches to pack the PSLV to its full capacity. There were over 114 separation events in a single flight, including the strap on motors and the stages of the rocket. The satellites themselves had to be deployed while making sure that they do not bump into each other during the separation. ISRO had to track 5,460 pairs of objects to ensure that there would be no collision during the launch.
The successful multi satellite launch was a threat to the US private spaceflight sector, which actually has a policy in place to prevent American companies from using “cheap” Indian launch services. ISRO’s commercial wing, Antrix was able to bag the order through international intermediaries and benefitted from a lack of the necessary launch capacity among commercial, US-based launch services. After US companies develop the launch vehicles to serve demand, the contracts to ISRO are expected to reduce. The next generation launch vehicles currently in development include NASA’s Space Launch System, Blue Origin’s New Glenn and United Launch Alliance’s Vulcan.
In May 2017, ISRO launched the Geosynchronous Satellite Launch Vehicle (GSLV) with the South Asia Satellite on board. ISRO did not put up a livestream of the launch on its web site. The national television network DD was also surprisingly silent, with no pre-launch programming or live launch coverage.
The satellite has 12 transponders, with at least one dedicated to each participating nation and was a pet project for Prime Minister Narendra Modi. The South Asia Satellite has gone under many names in its three-year journey from conception to deployment.
It was initially called the SAARC satellite, but Pakistan played spoilsport and withdrew itself from the initiative, after which the spacecraft was renamed. ISRO just went with a name it had designated to the satellite and called it the GSAT-9. Sri Lanka, Bhutan, Maldives, Nepal, Bangladesh were all involved in the satellite, and Afghanistan came on board too, a few months before the launch.
The GSLV-F09 mission provided a big boost to India’s space diplomacy. The reason for the secrecy was revealed about half an hour after the successful deployment of the satellite. The Prime Minister of India, Narendra Modi, welcomed the leaders of all the participating nations to a surprise video conference. As the conference hopped, skipped and jumped through the capitals of countries ranging from Kabul to Khatmandu to Colombo, every head of state praised the initiative and outlined how the satellite would benefit the people in their countries, as well as boost cooperation in the region, which is home to over one and a half billion people.
The Prime Minister explained the usefulness of the satellite in his Mann Ki Baat podcast after the launch, "Natural resources mapping, telemedicine, the field of education, deeper IT connectivity or fostering people-to-people contact, this satellite will prove to be a boon in the progress of the entire region. It is an important step by India to enhance cooperation with the entire South Asia...It is an invaluable gift. This is an appropriate example of our commitment towards South Asia. I welcome all the South Asian countries who have joined us on this momentous endeavour."
We are a united family of South Asian countries, united in our pursuit of peace, progress & prosperity of our region & the entire humankind.
— Narendra Modi (@narendramodi) May 5, 2017
ISRO’s next flight just a month later in June 2017 was also historic. ISRO deployed the GSAT-19 into orbit using its heaviest launch vehicle yet, the GSLV-MKIII. The rocket was informally referred to as “Fat Boy” owing to its stocky profile, but soon earned the monikers “obedient boy” and “Baahubali” after the launch. ISRO personnel have also referred to it as India’s “workhorse” of the future, a title currently held by the PSLV. It was the maiden developmental flight of the GSLV MKIII, the first to be realised using an indigenously developed cryogenic engine, and it managed to launch the heaviest satellite that India had produced. With the launch, India joined a club of a select few nations with the capability of launching satellites weighing more than three tonnes and cemented its place in the global satellite launch industry.
In the same month, ISRO had yet another multi satellite launch planned, the PSLV-C38 mission. It was the fortieth flight of the reliable PSLV, and this time, there were 31 satellites on board. The primary payload on board was a CartoSat 2 series satellite. The launch took place without a hitch and the 23 minute flight took place exactly as planned.
Eight of the satellites were from the QB50 swarm, an international academic collaboration. As the collaboration was managed by an Institute in Belgium, ISRO listed three satellites as coming from that country when they were actually from China and the United Kingdom. India deployed a Chinese academic satellite this year. That was not the only surprise in the mission. Piggybacking on two of the academic satellites were tiny prototypes of interstellar spacecraft known as “sprites”. The prototypes were developed by Breakthrough Starshot and were the first to be launched into space. They were also the smallest satellites that ground stations could establish communications with.
With the August 2017 mission of the PSLV-C39, ISRO broke the flawless, 24-year record maintained by the reliable launch vehicle. Except for the maiden flight of the rocket, none of the previous forty missions had failed. The spaceflight actually proceeded smoothly for most of the mission duration. It was only in the very last minute that the heat shield, also known as the payload fairing, failed to separate from the rocket. This is the tip of the PSLV, which opens up like a flower with two petals, deploying the satellite into its intended orbit. On this unfortunate flight, the satellite was trapped within the heat shield.
— T R B Rajaa (@TRBRajaa) August 31, 2017
The space agency was unfazed by the failure and committed to resume launches by the end of the year. Fortunately, it was the best mission to fail on as there was only one passenger on board, the IRNSS-1H navigation satellite. The IRNSS constellation of navigation satellites will provide geolocation services across the country. ISRO is tasked with maintaining the swarm of satellites and the IRNSS-1H was meant to be part of that swarm. It's not an irreplaceable member of that swarm, however.
An exciting upcoming PSLV flight is a trip to the moon that TeamIndus from India and Hakuto from Japan will rideshare on in an attempt to win the Google Lunar XPrize.
Mangalyaan continues to observe Mars well beyond its planned mission duration
ISRO’s maiden interplanetary mission, Mangalyaan, was hailed for being one of the most cost effective spacecraft to make the jump from Earth to Mars. When the Mars Orbiter Mission or (MOM) started orbiting the Red Planet in September 2014, India became the only nation in the world to succeed in the first attempt of such an endeavour.
MOM was meant to have a planned mission duration of only six months, but in mid June 2015, ISRO indicated that there was enough fuel on board to continue the mission duration for many years.
Mangalyaan celebrated a number of milestones in 2017. In September 2017, the MOM mission celebrated three years in orbit around Mars and showed absolutely no sign of stopping. ISRO said, “As the country's low-cost Mars Orbiter Mission completes three years in its Martian orbit, the satellite is in good health and continues to work as expected.”
In June 2017, MOM completed 1,000 Earth days in orbit around Mars, or 388 laps around the Red Planet. Mangalyaan was meant to be a technology demonstration mission. Its primary objective was to give ISRO engineers the experience of executing an interplanetary mission.
The science objectives of MOM were secondary The five scientific payloads on the spacecraft have served well over the extended mission duration, studying the surface and the atmosphere of the Red Planet. The space agency allows researchers in the country to use data gathered by MOM for their scientific studies.
In November 2017, ISRO released images of volcanic summits in the Tharsis region of Mars, including Olympus Mons, the tallest mountain in the solar system.
In March 2017, the MOM observed superhot argon in the upper regions of the Martian atmosphere. The discovery of such particles in the region provides hints about the atmosphere around Mars and helps scientists understand why the Martian atmosphere is escaping at such a rapid pace.
All these milestones, and the continued observations of the Red Planet, were possible because of a crafty bit of manoeuvring by ISRO engineers early in the year. The solar panels on board the spacecraft need to be exposed to sunlight to keep the batteries charged. The spacecraft cannot manoeuvre if it is not exposed to the Sun for more than 8 hours.
In every orbit, the spacecraft spends a certain amount of time where the solar panels are not exposed to the sunlight. The scientists at ISRO had been closely monitoring the duration of this blackout in every orbit, and intervened in January to adjust the orbit, just when a long blackout would have meant that ISRO could no longer control MOM.
ISRO plans future missions to explore the solar system
ISRO also announced several plans to continue exploring other bodies in the solar system. Early in the year, a team of ISRO scientists were engaged in studying the feasibility of follow-up missions to the Moon and Mars, considering the successes of Chandrayaan and Mangalyaan. ISRO was also formulating a plan for a maiden flight to Venus.
In April 2017, ISRO started inviting proposals for scientific payloads to be carried on the mission to Venus. The allocated weight limit for science instruments on board the Venus mission was 175 kg, which was much more than MOM, which carried only 15 kg of scientific instruments.
In August 2017, an initial budget of Rs 10 lakh was sanctioned for the Venus mission. ISRO plans to inject an orbiter in an elliptical orbit around Venus, which would allow it to capture images of Venus from never before seen angles. A similar approach allowed MOM to capture unique images of Mars and its moons.
ISRO has announced plans to launch Chanrayaan-2, its follow up mission to the Moon, in March 2018 on a GSLV MKII rocket.
The mission has three components, an orbiter, a lander and a rover. The orbiter will be deployed at an altitude of 100 kilometres above the lunar surface. The lander will execute a soft landing and has a propulsion system on board to slow down the craft as it approaches the surface. Finally, a six-wheeled rover will investigate the surface of the Moon. The lander, rover and orbiter together will perform mineralogical and elemental studies of the Lunar surface.
Even a dysfunctional Chandrayaan-1 mission, which ISRO had lost contact with in 2009, helped to advance science. The tiny spacecraft proved to be a perfect target to try out NASA’s fancy new ground-based tracking hardware. The US Space agency managed to track down the orbiter and were praised for the feat by former ISRO chairman, Madhavan Nair.
Gravitational waves from a pair of colliding neutron stars were detected for the first time
The LIGO-Virgo collaboration announced the first detection of gravitational waves from a pair of colliding neutron stars in October 2017. Astronomers and researchers were studying the event since August 2017 itself, when the ripples in spacetime first reached the Earth.
More than 70 space and ground-based astronomical instruments around the world interrupted their scheduled observation campaigns and turned their gaze towards the collision for conducting follow-up observations.
Peter Shawhan, the principal investigator of the Ligo Science Collaboration called it the “most intensely observed astronomical event in history.” It was the first time that scientists had observed gravitational waves and electromagnetic radiation in the visible spectrum from the same source. The event was also the closest identified source of gravitational waves.
The event has been dubbed GW170817 and is located within a galaxy known as NGC 4993 at a distance of about 130 million light years from the Earth, in the direction of the Hydra constellation. A series of papers published in the journal Science, outlined the various studies by the different astronomical instruments.
The event heralded a new era of astronomy based on the observation of gravitational waves as well as of astronomy based on multiple instruments studying the same event, this is known as multi-messenger astronomy. Over 12 of NASA’s telescopes and observatories captured the event, including Hubble, Spitzer, Fermi and Chandra.
Astronomical assets belonging to India also played a role in studying the event. The Himalayan Chandra Telescope at Hanle, Ladakh, the Giant Metrewave Radio Telescope (GMRT) in Pune and AstroSat, India’s first dedicated Space Observatory, all increased the scientific understanding of the event.
Over 40 scientists from 13 Indian institutions contributed to studying the observations by the LIGO-Virgo collaboration, part of a global team of 1,200 scientists from over 100 intuitions around the world. The observations indicate that the collision resulted in the production of about 10,000 Earth masses of gold.
ISRO's certainly been busy this year.