Why NASA Trusts 1970s Processors

The truth is, the smartphone in your pocket has about 100,000 times more processing power than the computers steering our most advanced spacecraft. You might assume space agencies use the most futuristic, advanced quantum processors available to humanity.

Instead, the Mars Perseverance rover is currently hunting for alien life using a modified PowerPC 750 processor. That is the exact same chip that powered Apple’s original translucent blue iMacs back in 1998. It operates at a remarkably sluggish 200 megahertz.

Even the mighty Orion spacecraft, designed to take humans back to the Moon and beyond, relies on processors built on a 1970s architecture.

The Void is Hostile

But wait — if we have access to chips with billions of transistors here on Earth, why send a $2.7 billion rover into the void with a brain from the dial-up era?

The answer comes down to a silent, invisible killer. Deep space is saturated with cosmic rays and high-energy particles ejected by the sun.

Down here, Earth’s magnetic field protects our delicate electronics. Up there, a single proton travelling at 299,000 kilometers per second can smash straight through a silicon chip.

When that happens, the physical impact can flip a binary zero to a one. This terrifying phenomenon is called a single-event upset.

If a random bit flips in your laptop, your browser crashes. If a bit flips during a planetary descent, the spacecraft becomes a very expensive crater. We already know the catastrophic consequences of small technical failures; just look at The Glitch That Almost Ended Us.

The Beauty of Clunky Transistors

Modern computer chips achieve their blistering speeds by packing transistors incredibly close together. Today, those transistors are measured in nanometers. They are microscopic, fragile, and highly sensitive to any electrical disturbance.

Older chips, however, are physically larger. Their transistors are bulky and require significantly more energy to flip from a zero to a one.

That physical clunkiness is precisely their superpower. A stray cosmic ray striking a 1970s-style processor simply doesn’t pack enough of a punch to accidentally flip its massive, power-hungry switches.

The older tech is practically immune to the radiation that would instantly fry a modern iPhone. NASA isn’t choosing old technology to save money. They are choosing it because it simply refuses to die.

Forged in Fire

To ensure these legacy chips survive, NASA puts them through a rigorous hardening process. They aren’t just taking old circuit boards out of a dusty storage closet.

Engineers rebuild these vintage architectures using specialized manufacturing techniques. They swap out standard silicon for sapphire wafers, which are highly resistant to radiation.

They bake the processors in vacuum chambers at exactly 125°C and freeze them down to -55°C. They bombard them with heavy ions to simulate the brutal conditions of deep space. Sometimes, extreme patience and extensive testing are the ultimate survival tools off-world, a concept perfectly illustrated in Why They Waited 144 Hours to Leave.

The final product costs upwards of $200,000 per chip. It looks like a retro relic, but it boasts a failure rate of almost absolute zero.

Complex, modern software also introduces millions of lines of code. More code means more places for critical errors to hide—a lesson learned the hard way in The Keystroke That Broke the World.

The Slow Path to the Stars

By keeping the hardware simple and relying on decades-old architecture, space agencies drastically reduce the chance of a fatal software loop. The computers onboard only do exactly what they need to do, nothing more.

They monitor life support, calculate trajectories, and fire thrusters. They do not run background apps, and they certainly don’t need fancy graphics processing.

You’ve probably heard that the Apollo 11 moon landing was achieved with less computing power than a modern musical greeting card. But what most people miss is that this wasn’t just a limitation of the era.

It established a philosophy of ruthless simplicity that keeps astronauts alive today. When you are 400,000 kilometers from the nearest IT support desk, you don’t want speed. You want absolute, unshakable reliability.

Will we ever reach a point where we trust our delicate modern silicon enough to guide us to the next star system, or are we destined to conquer the galaxy using the ghosts of 1970s computing?