The TLDR: On Thursday, something went terribly wrong as the Indian Space Research Organization tried to launch a state-of-the-art satellite. The reason: a huge technical glitch in the third and final stage of the mission. Here’s a quick look at why the launch failed—and why it matters. 

The mission explained

The launch took place at the Satish Dhawan Space Centre, Sriharikota at 05.43 am. The GSLV-F10 rocket was supposed to carry an earth observation satellite EOS-03 and place it in orbit. The satellite is one of the country’s most sophisticated Earth imaging satellites and it successful deployment would have offered important benefits:

“Reports said that the advanced imaging satellite had been described as a ‘game changer’ for India with its high resolution cameras allowing constant, real-time monitoring of the Indian landmass and the oceans. Among the key areas where it could have proved its utility is defence, enabling ‘special attention to the country’s borders for security reasons.’’’

The satellite would also allow early monitoring of natural disasters such as floods and cyclones. 

The plan: The rocket would lift off and place the satellite in something called a geosynchronous transfer orbit (GTO)—a highly elliptical intermediate path around Earth. The satellite would then use its own propulsion system to make its way to a final geostationary orbit. The launch was scheduled for Thursday morning—but went totally awry four minutes and 55 seconds after liftoff.

What went wrong

The first two stages of the mission went as planned, but a technical malfunction disrupted the actual launch of the satellite.

What went right: The 51.70-metre tall rocket lifted off the launch pad on cue at 5.43 am. The second stage of the rocket—the second from the bottom of the rocket—also separated smoothly. This is when the upper stage (section) of the rocket was supposed to ignite—and that’s when everything went wrong.

What went wrong: The upper stage of this rocket has a ‘cryogenic engine’ to propel itself and reach the right location to place the satellite. Such engines use a mix of liquid oxygen and liquid hydrogen. This engine failed to ignite. Instead, the stage of the rocket started to roll and lose orientation, also losing velocity and altitude. 

The reasons for failure: ISRO has not offered a detailed explanation of the malfunction, with its chairman merely saying: “There was an anomaly observed in the cryogenic stage.” All we know is that cryogenic engines have a mixed record. 

• In 2010, the very first flight with a very similar cryogenic engine—made in India but modelled on a Russian design—failed to ignite.
• Eight months later, another launch—this time with a Russia-made cryogenic engine—also failed due to a malfunction. 
• OTOH, since then, the GSLV Mk-II rocket has carried out six other launches—all using that same India-made cryogenic engine in the upper stage. The last one was in December 2018 which successfully deposited a communication satellite into its orbit.
• So Thursday’s failure is not easily explained by any inherent flaw in the engine.

Point to note: Former ISRO chief Madhavan Nair points out that ISRO has a far better track record with cryogenic engines than its European counterparts:

“Normally, the cryogenic stage is the most difficult one compared to all other rocket propulsions… There is a finite possibility of failure with any such complex system. We need not be disappointed. But at the same time, we should go to the root cause and fix it so that we don't repeat."

What to watch for: There are no more launches of this GSLV Mk-II rocket scheduled for this year. But there are several critical missions coming up in 2022 and 2023. If there is a serious issue with the engine it will have a knock-on effect—delaying future missions, especially a project with NASA called NISAR. The plan is to launch a joint Earth observation satellite to monitor the entire planet in a 12-day cycle.

The bottomline: Ad astra, per aspera—to the stars, through hardship.

Reading list

Space News has the best description of what went wrong. Mint and News18 have more detailed explainers on the mission. Indian Express does an excellent job of placing this failure within the context of other missions.