Home » Technology » This high-speed space sail can take us to the following star systems February 20, 2022
Artist’s rendering of the Starshot Lightsail spacecraft during acceleration with a laser array on the ground.
Masumi Shibata / hacking initiatives
Only about 4 light years from our solar system is Alpha Centauri, another bustling space district. It is installed by three stars With the same function as our sun, it carries planets similar to our famous eight bodies and may have an Earth twin that hangs out in the habitable zone. Almost like an alternate reality, the star system is a bewildering area for space explorers.
There is only one clear case. With our current technology, sent spacecraft won’t reach Alpha Centauri until around the year 82022. That’s why in 2016 the late astrophysicist Stephen Hawking and investor Yuri Milner launched Starshot hack – An initiative to send wafer-sized space probes to Alpha Centauri. at 20% the speed of light, reducing the enormous travel time to just 20 years.
Receive the CNET Science newsletter
Explore the greatest mysteries of our planet and beyond with the CNET Science newsletter. Monday delivered.
Their scheme focuses on an optical sail that harnesses the power of photons, also called light particles, emitted by a laser on the ground, rather than the wind like a traditional sail. Although it’s a perfect match for the sci-fi technology of Star Trek, the idea has grown in popularity to the point that researchers around the world are beginning to study how to operate the alien gadget, hoping to produce a hyper -engine that explodes through the universe at dizzying rates.
One such team from the University of Pennsylvania is tackling a big piece of the puzzle. à Some articles published this month in Nano LettersAnd Researchers have proposed a way to ensure these innovative spacecraft aren’t torn apart by intense laser pulses during the two-decade interstellar flight. Essentially, the researchers suggest that the sail should “flow” through the vacuum of space like the sails of ordinary boats through the winds of Earth.
Illustration of what one of the stars of Alpha Centauri, Proxima Centauri, might look like. The red dwarf star can be seen in the center, its nearby planets, and the other two Alpha Centauri binary stars in the background.
“Some of the light sail numbers from the start were choppy, some weren’t, but they haven’t been well studied,” said study author Igor Bargatin, associate professor in the Department of Mechanical Engineering and Mechanics. applied from the University of Pennsylvania. “What we have done is show that you absolutely have to inflate.
“We realized that people haven’t really looked at the mechanics of the problem, especially the possibility of crying,” Bargatin added. “We want to make sure that idea comes to fruition, and when it comes to fruition, people pay attention to things that can happen during acceleration.
“We don’t want these sails to fail.”
Interstellar Ship Parameters
Imagine a boat venturing out to sea with a sail attached. The sail will rise with every gust of wind and propel the ship forward. This thrust is caused by the backing of the wind hitting the sail, creating pressure.
Bright sails are not much different.
“When photons hit our light sail, they are reflected and also create pressure,” Bargatin said. “The exact mechanism is a bit different because we’re talking about light air molecules versus real air molecules. But it still creates pressure in both directions. In fact, such devices have already proven their efficiency to some extent.
In 2010, the Japanese Aerospace Exploration Agency He launched a light sail mission called Ikaros She considered it a success. in 2019, LightSail demo 2 Affiliate trial. Funded by a Kickstarter campaign launched by Bill Nye and Neil DeGrasse Tyson, he flew a small satellite into space using the pure power of a photon.
The solar sail that was at the center of the Japanese Ikarus project.
Japan Aerospace Exploration Agency
But both Ikaros and LightSail 2 use light emitted from the sun, unlike Breakthrough Starshot’s laser vision.
Although sunlight reduces the risk of tears, it is too weak for a Starshot attempt. Also, says Bargattin, the light pulses from the Starshot should occur in a relatively short time because once the light sail is too far from Earth, scientists lose their ability to accelerate it effectively.
In short, to reach one-fifth the speed of light – to be able to reach Alpha Centauri in the required twenty years – within a strict window, the lights would need extremely powerful light pulses that are only possible with a laser. .
Artist’s rendering of Lightsail 2 orbiting Earth.
“The pressures designed on our photonic nails are not huge,” Bargatin said. “It’s almost like having a penny in your hand.” Scientifically speaking, the pressure amounts to about 10 Pa, says Bargatin, but consider how we live our lives without worrying about light pressure. Absoutely.
Ten Light Power Steps require a large amount of laser energy, so unlike the Icarus Dance of Soft Sunlight, light nails emitted by extremely harsh laser pulses can be damaged.
How to build a permanent light sail
According to the researchers, the powerful laser pulses can create pressure strong enough to arch and tear the plate like the sail of a taut boat that could explode if giant gusts of wind hit it.
They believe that lights should have the ability to “puff up” and form a somewhat curved shape like an awning. Bargatin explains that the length of the sail and the radius of curvature should be around 3 meters. In their new papers, the authors describe the geometric measures that ensure optimal distension.
Even a light sail protected from tears will encounter other obstacles. To overcome such problems, the main parameter to consider is the material of the sail. Panels should be strong for durability and lightweight to reduce laser power and efficiently reflect light for optimal thrust and conduct away heat generated by laser pulses.
Bargatin says if the last part is not supported, she can literally sail fusion in the space.
“You can find a bunch of materials,” Bargatin said. The thickness of this material and the curvilinear geometry will allow the sail to overcome the pressures we are currently designing for,” noting that his team is primarily studying a material called molybdenum disulfide.
In the grand scheme of things, however, building a massive laser array that would send a beam of light forward would be a major hurdle. Researchers working in space communications are also looking to retrieve information from a chip probe attached to the optical sail, Bargatin said.
The microchip probe offered by Starshot.
If the Breakthrough Starshot mechanism ever works, it will be a true testament to mankind’s scientific genius. In announcing the organization’s formidable goals six years ago, Hawking’s Monument:
“I think what makes us unique is going beyond our limits. Gravity holds us to the ground, but I just flew to America. I lost my voice, but I can still speak, thanks to my speech-to-text device. How to transcend these limits?
With our minds and our machines.