Astronaut Ed Lu Looks to Save Earth by Mapping the Path of a Million Asteroids

by Brian Caulfield

Sooner or later, the house always wins.

That was the message former NASA astronaut Ed Lu gave at our Santa Clara headquarters as part of a series of talks to NVIDIA employees Wednesday.

Lu spoke about the risks to humanity posed by asteroids — and outlined his effort to understand and lessen them.

“You can’t win a game of chance forever,” Lu said. “In the game of cosmic roulette we’re not the house – we have got to change the game at some point, or we become like the dinosaurs.”

Lu’s Sentinel Mission aims to detect all these asteroids within several years. Mapping their paths — while accounting for gravitational variables such as Jupiter, other large asteroids and even the shape of the Sun — is a huge computing job. And could be a life-saving use of GPU processing power.

Former NASA astronaut Ed Lu explains how he hopes to keep an eye out for killer asteroids.

Lu, a physicist and veteran of two Space Shuttle missions, has gathered a small team of scientists. Their aim is to build a space-based infrared telescope they call “Sentinel.”

His team’s design is sensitive enough to find an asteroid the size and color of a charcoal briquette — at a distance of 30,000 miles, against the black backdrop of space.

Now he’s raising the funds he needs to get it built and launched.

A Dangerous Game

To be sure, Lu explained, the risks of a space rock destroying a city – or our entire civilization – this year are slight. Over time, though, the risk grows.

There’s a 1 percent chance that one the size of a football stadium will hit in our lifetime. But every 30-40 million years a rock large enough to kill everything less hardy than cockroaches slams into Earth.

There are about 1 million asteroids swirling around the sun that could intersect with Earth’s orbit.

“You can get away with running across the street with your eyes closed, once,” Lu said. “But if you do it 100 times, you’re going to get hit.”

That’s no good. The upside: it doesn’t take much to knock a killer asteroid off course.

Saving the world, on a modest budget.

Given enough lead time, changing an object’s speed by a few millimeters per second can be enough to cause something that will hit our planet to speed right by us.

Cancelling the Apocalypse

It’s doable. In fact, Lu says, we’ve done it before, slamming a probe the size of an easy chair into an asteroid, and altering its trajectory.

“We’re at the stage at which we can change the future story for our planet, for our solar system, that’s what we’re trying to do,” Lu said. “We’re trying to save the world.”

The trick, Lu says, is identifying rocks that are on course to hit us. Astronomers are already tracking most of the big stuff — we think.

That’s where his latest project comes in. He’s raising money to fund a mission — dubbed Sentinel — that will take a more comprehensive look at what’s out there.

He estimates the cost of his project is around $500 million. That’s comparable to the price tag of a new wing for a museum.

“If you look at the cost of making a movie like ‘Armageddon,’ it’s about half the cost of Sentinel.”

Or we can just keep playing roulette.

“At this point, we simply do not know when the next major impact is going to happen,” Lu said.

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