Space exploitation vs space exploration: Humanity has much to learn from the Voyager probes

Interview It will soon be half a century since NASA's Voyager probes were launched on a tour of the solar system. The reason for their unprecedented longevity is unprecedented, but modern realities mean that we might not see their like again.

Dr Garry E Hunt was one of the original imaging team members and tells The Register why he thinks the veteran spacecraft had endured for so long. "Brilliant engineering," he says. "Let's be honest, the scientific community gets credit, but it's the engineers that really deserve the credit."

The twin Voyager spacecraft were launched in 1977. Both were to perform flybys of Jupiter and Saturn, but while Voyager 1 would visit Saturn's Moon, Titan, Voyager 2 could perform a Grand Tour of the planets, taking in Neptune and Uranus. "[Former US President Richard] Nixon," says Hunt, "only funded it as far as Saturn; he refused to have it funded for longer…"

However, both spacecraft were in good health thanks to some canny engineering decisions and plenty of redundant systems. So the Tour continued, with memorable shots of Uranus and Neptune before the famous Pale Blue Dot image was taken.

Over 30 years on, the Solar System family portrait remains Hunt's proudest moment from the mission: "If you ask me what was the most important picture we took? … The picture that showed the entire family of the Solar System from just beyond the orbit of Neptune, which showed that the Earth was a tiny tiny blue dot.

"And that was a big wake-up call to everybody to say, 'Hey guys, we've got a serious problem. That's the only place that we've found in the solar system that we can live. That's our home. Don't mess it up'."

Could a project like Voyager happen now? Hunt is not so sure: "We have a problem with politics. The US is having a fundamental problem with funding its missions. The budget has been trimmed by Biden, trimmed further by the Senate, decisions are not being made because the election is coming, the pandemic affected establishments like JPL and others … so all these are factors.

"Furthermore, countries say 'Look, it's not just science you get out of this, what's the value to the economy? … We're not prepared to wait 10 or 20 years for something. We need quick results which are beneficial for the economy.

"So I think we're going to be looking at missions to the very distant parts of our solar system somewhat differently. We are looking at the Moon, Mars, and the asteroids somewhat differently. In the past, we talked about space exploration. I think we're looking at a re-spelling. We're looking at space exploitation now."

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While acknowledging the benefits, Hunt also worries about a more commercial approach. The load and risk are, in theory, spread, yet the desire for quick returns remains. "If you're making something in the most cost-effective way, the cheapest way, you cut corners."

"I look back at the way space missions were developed in the past; the number of redundant systems we had on Voyager; the number of quality checks to make sure nothing failed.

"Will the commercial sector be having the same approach?"

Hunt notes recent issues with NASA's Artemis program and says, "I wonder whether we would have had some these problems in the old days with NASA working the way it did…"

Hunt, however, does accept the modern need to demonstrate the benefits of space exploration. With other pressures on the economy, "can we really afford to do all these things that go on for 10 – 20 years? So return [on investment] has got to be a parameter that is examined very strongly when making decisions."

Things have, of course, moved on since the era of Voyager, even if the chemical rocket technology used to launch the probes continues to power modern rockets. The UK has demonstrated prowess in developing spacecraft systems, but Hunt says the future lies beyond that niche.

"The future of space," he says, "involves everything from high finance to insurance, to engineering, right the way through the spectrum … are we going to be the leaders?"

Hunt's career has been varied. He worked on the Viking missions to Mars and was involved in payloads on the early Shuttle missions. Today, he advises industry and politicians. He is very concerned about climate change and the environment, which is understandable when considering his background in atmospheric science.

Of the Earth, he says, "We're making a jolly good mess of it."

However, Hunt's enthusiasm for science remains undimmed. He is delighted that Voyager data continues to be used for research. "Some of the latest work on Neptune to actually understand and get the correct colors and such like involves going back to the original Voyager data. Isn't that stunning?"

Having noted the retrospective importance now placed on missions from decades past that demonstrated the potential for manufacturing in space, Hunt still expresses awe at the science being generated by modern spacecraft. "The James Webb [space telescope]," he says, "is just unbelievable … they [the James Webb Space Telescope and Hubble] are just stunning."

The Voyager probes continue to demonstrate the benefit of robot explorers. Modern spacecraft like the James Webb Space Telescope are doing the same. The Reg can but hope that any shift from exploration to exploitation won't sacrifice that.

And Hunt? He's looking forward to one more trip to the US to celebrate Voyager's 50th anniversary. "When Voyager's 50th birthday comes up, I think I'd like to be back in JPL," he tells us.

Will the Voyagers still be running? Perhaps.

At the moment, NASA's best guess is that while science data will cease to be collected after 2025, there is every chance that engineering data could continue to be returned for several more years. Both spacecraft could remain in range of the Deep Space Network through 2036, depending on there being enough power remaining to transmit a signal back to Earth. ®