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Vikram lander
The Vikram lander, which carried a small rover called Pragya, being prepared for launch earlier this year. ISRO lost contact with the lander during its descent to the lunar surface Friday. (credit: ISRO)

Schrödinger’s lander


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As it rolled out its plans to support commercial lunar lander missions last year, NASA officials often talked about taking “shots on goal.” The idea was to accept there would be some level of failures: just as not every soccer ball or hockey puck fired at a goal makes it into the net, not every lander will make it to the surface intact. It’s a good way to set expectations and deal with missions that don’t make it—so long as the failure rate isn’t 100 percent.

“We came very close, but we will need to cover more ground in the times to come,” Modi said. “India is suffering, but there will be many more opportunities to be proud and rejoice.”

While the first landers for NASA’s Commercial Lunar Payload Services (CLPS) program likely won’t fly until 2021, the space community is already getting some practice about how to deal with failure. In April, Beresheet, the lander built by Israel Aerospace Industries (IAI) for SpaceIL, a former Google Lunar X PRIZE competitor, attempted to touch down on the Moon. Viewers watched a webcast from mission control in Israel for live updates as the lander descended, only to suffer a malfunction in its final descent.

It took only minutes for mission leadership to tell the audience in the room, which included Prime Minister Benjamin Netanyahu, as well as those watching online that this shot hadn’t made it into the goal. “We had a failure of the spacecraft. We unfortunately have not managed to land successfully,” IAI’s Opher Doron said. (See “If at first you don’t succeed…”, The Space Review, April 15, 2019.)

Nearly five months later, the scene shifted to India, where it was the Indian Space Research Organisation’s turn to land a spacecraft on the Moon. Vikram, the lander included on the Chandrayaan-2 mission that launched in July, was set to touch down just before 4:30 pm EDT Friday (2 am Indian time Saturday) in the south polar regions of the Moon. If successful, it would make not only India just the fourth nation to soft-land on the Moon, but also the first to touch down anywhere near the poles, where deposits of water ice may exist in regions of craters in perpetual shadow.

Again there was a live webcast from mission control, where again the country’s prime minister, Narendra Modi, was in attendance, with screens showing telemetry from the lander. The initial phases of the descent went well, with updates punctuated by polite applause.

But then, after the lander completed the initial, or “rough braking,” portion of its descent, something went wrong. Mission control went quiet. There were no updates, and no applause. One screen appeared to show that the lander had deviated from its planned trajectory, while another, with an animation of the lander’s descent, showed the lander flipping, although it wasn’t clear if that represented the actual orientation of the lander or just a display glitch.

There were no updates because there was no communications with the lander. Finally, after an extended pause, ISRO made a brief announcement. “Vikram Lander descent was as planned and normal performance was observed up to an altitude of 2.1 kilometers. Subsequently communication from lander to the ground stations was lost. Data is being analyzed.” And that was it.

Modi, in comments a short time later, suggested that the lander had failed. “We came very close, but we will need to cover more ground in the times to come,” he said. “India is suffering, but there will be many more opportunities to be proud and rejoice.” Earlier, he consoled ISRO chairman Kailasavadivoo Sivan, hugging him in mission control.

ISRO has offered little in the way of updated information about the mission since the landing attempt.

But the status of the Vikram lander still isn’t clear, more than three days after it reached the surface. While most people assumed the landing was a failure, based on the available information and Modi’s comments, a trickle of information coming out of ISRO suggested that perhaps the lander was intact on the surface. Sivan told some Indian media outlets that cameras on the Chandrayaan-2 orbiter had imaged the lander, with some claiming that they showed the lander intact but not necessarily upright. All agreed, though, that the lander was not in communications with the Earth.

ISRO has offered little in the way of updated information about the mission since the landing attempt. The last official update, released Saturday, didn’t declare the lander a failure, and, in fact, said little about the lander itself: it focused on the science that the orbiter will still be able to do and that “90 to 95 percent of the mission objectives have been accomplished.”

Since then ISRO has released no further official updates about the status of the lander, nor any of the orbiter images that purport to show the lander. (There’s also confusion about whether the images are “thermal,” presumably infrared, images, or optical ones from the orbiter’s high-resolution camera.) The last statement from ISRO, at the time this article was being prepared for publication Monday, was one stating that any social media accounts claiming to be those of Sivan are not authentic.

It’s understandable that ISRO may take some time to make every effort to restore contact with Vikram before declaring the lander a failure. Nearly two decades ago, NASA’s Mars Polar Lander failed to make contact after its scheduled landing, leading to an agonizing process that stretched out for days and weeks before the mission was declared a failure. However, in that case, NASA at least provided regular updates about the status of those efforts, something ISRO has failed to do here, a disservice to both the Indian people who fund the agency and the broader space community.

That’s one of the lessons that companies participating in the CLPS program should take away from this. As private ventures, there may be a reticence to freely share information about the status of their missions: they are, after all, not government agencies with the same expectations of openness. However, they will be carrying NASA-funded payloads (and, potentially, payloads from agencies of other governments) and thus there will be a desire for regular, prompt updates about those landers. Hiding bad news doesn’t make it go away.

A second lesson is that, half a century after Apollo 11, landing on the moon is still very difficult. If Vikram indeed failed to land successfully (which includes landing intact but so hard that the spacecraft is damaged and not operational), the world will have gone one-for-three in lunar landings this year, with China’s Chang’e-4 the sole success.

It was one thing for Beresheet to fail: the lander was built on a modest budget by a small team. Chandrayaan-2, though, was a flagship for India’s space program, with thousands involved. That it may have suffered a problem during descent that destroyed or crippled the lander demonstrates how tough of a challenge landing on the Moon really is—and highlights the capabilities of China, with its two successful lunar landings, or the US with its extensive record of successful landings not just on the Moon but also Mars.

Another lesson, not directly related to the Vikram lander, is that failures need not always involve spacecraft debris scattered across the lunar regolith. Immediately after the crash of Beresheet, SpaceIL announced it would pursue a second lander, dubbed Beresheet 2, and started to raise money for that mission.

Yet, in late June, the organization announced it was changing course. “This time, we will not go to the moon. Beresheet's journey to the Moon was already received as a successful, record-breaking journey. Instead we will seek out another, significant objective for Beresheet 2.0,” SpaceIL tweeted. “More details to follow.” Those details have not followed, more than two months after its announcement. IAI, though, is commercializing the Beresheet lander technology, announcing an agreement with a CLPS company, Firefly Aerospace, in July.

The “shots on goal” philosophy may be a good one for small robotic landers. It’s just that no one expected it to be so difficult to know if the shot made it into the goal.

One CLPS company has already discovered this lesson. In late May NASA awarded initial contracts to three companies—Astrobotic, Intuitive Machines, and OrbitBeyond—for carrying payloads on their missions. But in late July, two months after winning that award, OrbitBeyond said it was terminating its contract, valued at $97 million, because “internal corporate challenges” would keep it from implementing it. The company did not elaborate, although there were rumors the company was struggling to raise funding.

Whether or not ISRO ever establishes contract with Vikram, it’s clear that funding, building, and launching lunar landers is more difficult than many thought—and that’s before actually trying to get the landers safely onto the surface. Those challenges should not be underestimated by companies or space agencies.

The “shots on goal” philosophy may be a good one for small robotic landers. It’s just that no one expected it to be so difficult to know if the shot made it into the goal.


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