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Antimatter engines could be humanity’s ticket to interstellar travel.
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When antimatter particles come into contact with ordinary matter, it produces a lot of energy.
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If we learn to harness that energy, it can take us to Pluto in just a few weeks.
Interstellar travel is only something humanity has achieved in science fiction, such as Star Trek’s USS Enterprise, which used antimatter engines to travel across galaxies.
But antimatter isn’t just a science fiction trope. Antimatter really exists.
Elon Musk has called antimatter force “the ticket for interstellar travel,‘ and physicists like Ryan Weed are investigating how to exploit this.
Antimatter consists of particles that look almost exactly like ordinary matter, but with an opposite electrical charge. That means that when antimatter comes into contact with regular matter, they destroy both and can produce enormous amounts of energy.
“Destruction of antimatter and matter directly converts mass into energy,” Weed, co-founder and CEO of Positron Dynamics, a company working to develop an antimatter propulsion system, told Business Insider.
Just one gram of antimatter could cause an explosion comparable to that of an atomic bomb. It’s that kind of energy, some say, that could boldly and at record speed take us where no man has gone before.
Space travel at record speed
The advantage of all that energy is that it can be used to accelerate or decelerate spacecraft at breakneck speeds.
For example, let’s take a trip to our nearest galaxy, Proxima, about 4.2 light-years away.
An antimatter engine could theoretically accelerate a spacecraft at a speed of 1 g (9.8 meters per second squared) and get us to Proxima in just five years, Weed said in 2016. That’s 8,000 times faster than Voyager 1 – one of the fastest spacecraft in history – would do. to travel around half the distance, according to NASA.
Even within our own solar system, an antimatter-powered spacecraft could reach Pluto in 3.5 weeks, compared to the 9.5 years it took NASA’s New Horizons probe to arrive, Weed said.
Why we don’t have antimatter engines
The reason we don’t have antimatter engines, despite their enormous capabilities, has to do with cost, not technology.
Gerald Jackson, an accelerator physicist who worked on antimatter projects at Fermilab, told Forbes in 2016 that with enough funding we could have a prototype antimatter spacecraft within a decade.
The basic technology is there. Physicists armed with the most powerful particle accelerators in the world have created antiprotons and antihydrogen atoms.
The problem is that this kind of antimatter is incredibly expensive to make. It is considered the most expensive substance on earth. Jackson gave us an idea of how much an antimatter machine would cost to build and maintain.
Jackson is the founder, president and CEO of Hbar Technologies, which is working on a concept for an antimatter space sail to slow spacecraft traveling 1% to 10% of the speed of light – a useful design for orbiting a distant star. planet or moon you want to study.
Jackson said he has designed an asymmetric proton accelerator that can produce 20 grams of antimatter per year.
“For a 10-kilogram science package traveling at 2% of the speed of light, it would require 35 grams of antimatter to slow the spacecraft and inject it into orbit around Proxima Centauri,” Jackson told BI.
He said it would cost $8 billion to build a solar power plant for the massive energy needs of antimatter production and that it would cost $670 million a year to operate.
For now, the idea is just that. “There is currently no serious funding for advanced space propulsion concepts,” Jackson said.
However, there are other ways to produce antimatter. That’s what Weed focused his work on.
Weed’s concept involves positrons, the antimatter version of an electron.
Another kind of antimatter engine
Positrons “are thousands of times lighter than antiprotons and don’t have as much power to destroy,” Weed said.
The advantage, however, is that they occur naturally and don’t require a giant accelerator and billions of dollars to create.
Weed’s antimatter propulsion system is designed to use krypton-79 – a form of the element krypton that naturally emits positrons.
The engine system would first collect high-energy positrons from krypton-79 and then send them into a layer of regular matter, producing destruction energy. That energy would then cause a powerful fusion reaction to generate thrust for the spacecraft.
Although positrons may be less expensive to obtain than more powerful forms of antimatter, they are difficult to harness because they are highly energetic and must be slowed down or ‘moderated’. So building a prototype to test in space is still out of reach cost-wise, Weed said.
That’s the case for all antimatter propulsion designs. Over the decades, scientists have proposed dozens of concepts, but none have become reality.
For example, in 1953, Austrian physicist Eugen Sänger proposed a “photon rocket” that would run on positron destruction energy. And since the 1980s, there has been talk of thermal antimatter engines, which would use antimatter to heat liquid, gas or plasma to provide thrust.
“It’s not science fiction, but we won’t see it fly until there’s significant mission pull,” Weed said of his engine concept.
Can it work?
To build Weed’s concept on the scale of a spaceship, “the devil is in the technical details,” Paul M. Sutter, an astrophysicist and host of the podcast “Ask a Spaceman,” told BI.
“We’re talking about a device that uses truly enormous amounts of energy, which requires exquisite balance and control,” Sutter said.
Overall, that enormous energy is another obstacle preventing us from revolutionizing space travel. Because during testing, “if something goes wrong, these are big explosions,” Steve Howe, a physicist who worked with NASA on antimatter concepts in the 1990s, told BI.
“So we need the ability to test high energy density systems somewhere that doesn’t threaten the biosphere but still allows us to develop them,” says Howe, who thinks the moon would be a good test base. “And if something goes wrong, you’ll have melted a piece of the moon,” not the Earth, he added.
Antimatter tends to bring out the imagination in anyone who works on it. “But we need crazy but plausible ideas to go further into space, so it’s worth looking into,” Sutter said.
Weed echoes this sentiment, saying “until there is a compelling reason to get to the Kuiper Belt, the Solar Gravitational Lens or Alpha Centauri very quickly – or perhaps we try to bring back large asteroids for mining – progress will remain slow into the future .” this area.”
Read the original article on Business Insider