. 24/7 Space News .
How to design a sail that won't tear or melt on an interstellar voyage
by Staff Writers
Philadelphia PA (SPX) Feb 17, 2022

An artist's conception of the Starshot Lightsail spacecraft during acceleration by a ground-based laser array. Previous conceptions of lightsails have imagined them being passively pushed by light from the sun, but Starshot's laser-based approach requires rethinking the sail's shape and composition so it won't melt or tear during acceleration.

Astronomers have been waiting decades for the launch of the James Webb Space Telescope, which promises to peer farther into space than ever before. But if humans want to actually reach our nearest stellar neighbor, they will need to wait quite a bit longer: a probe sent to Alpha Centauri with a rocket would need roughly 80,000 years to make the trip.

Igor Bargatin, Associate Professor in the Department of Mechanical Engineering and Applied Mechanics, is trying to solve this futuristic problem with ideas taken from one of humanity's oldest transportation technologies: the sail.

As part of the Breakthrough Starshot Initiative, he and his colleagues are designing the size, shape and materials for a sail pushed not by wind, but by light.

Using nanoscopically thin materials and an array of powerful lasers, such a sail could carry a microchip-sized probe at a fifth of the speed of light, fast enough to make the trip to Alpha Centauri in roughly 20 years, rather than millennia.

"Reaching another star within our lifetimes is going to require relativistic speed, or something approaching the speed of light," Bargatin says. "The idea of a light sail has been around for some time, but we're just now figuring out how to make sure those designs survive the trip."

Much of the earlier research in the field has presumed that the sun would passively provide all of the energy that light sails would need to get moving. However, Starshot's plan to get its sails to relativistic speeds requires a much more focused source of energy. Once the sail is in orbit, a massive array of ground-based lasers would train their beams on it, providing a light intensity millions of times greater than the sun's.

Given that the lasers' target would be a three-meter-wide structure a thousand times thinner than a sheet of paper, figuring out how to prevent the sail from tearing or melting is a major design challenge.

Bargatin, Deep Jariwala, Assistant Professor in the Department of Electrical and Systems Engineering, and Aaswath Raman, Assistant Professor in the Department of Materials Science and Engineering at the UCLA Samueli School of Engineering, have now published a pair of papers in the journal Nano Letters that outline some of those fundamental specifications.

One paper, led by Bargatin, demonstrates that Starshot's light sails-proposed to be constructed out of ultrathin sheets of aluminum oxide and molybdenum disulfide-will need to billow like a parachute rather than remain flat, as much of the previous research assumed.

"The intuition here is that a very tight sail, whether it's on a sailboat or in space, is much more prone to tears," Bargatin says. "It's a relatively easy concept to grasp, but we needed to do some very complex math to actually show how these materials would behave at this scale."

Rather than a flat sheet, Bargatin and his colleagues suggest that a curved structure, roughly as deep as it is wide, would be most able to withstand the strain of the sail's hyper-acceleration, a pull thousands of times that of Earth's gravity.

"Laser photons will fill the sail much like air inflates a beach ball," says Matthew Campbell, a postdoctoral researcher in Bargatin's group and lead author on the first paper. "And we know that lightweight, pressurized containers should be spherical or cylindrical to avoid tears and cracks. Think of propane tanks or even fuel tanks on rockets."

The other paper, led by Raman, provides insights into how nanoscale patterning within the sail could most efficiently dissipate the heat that comes along with a laser beam a million times more powerful than the sun.

"If the sails absorb even a tiny fraction of the incident laser light, they'll heat up to very high temperatures," Raman explained. "To make sure they don't just disintegrate, we need to maximize their ability to radiate their heat away, which is the only mode of heat transfer available in space."

Earlier light-sail research showed that using a photonic crystal design, essentially studding the sail's "fabric" with regularly spaced holes, would maximize the structure's thermal radiation. The researchers' new paper adds another layer of periodicity: swatches of sail fabric lashed together in a grid.

With the spacing of the holes matching the wavelength of light and the spacing of the swatches matching the wavelength of thermal emission, the sail could withstand an even more powerful initial push, reducing the amount of time the lasers would need to stay on their target.

"A few years ago, even thinking or doing theoretical work on this type of concept was considered far-fetched," Jariwala says. "Now, we not only have a design, but the design is grounded in real materials available in our labs. Our plan for the future would be to make such structures at small scales and test them with high-power lasers."

Pawan Kumar, a postdoctoral researcher in Jariwala's lab, as well as John Brewer and Sachin Kulkarni, members of Raman's lab at UCLA Samueli, contributed to this research.

Breakthrough Starshot is part of the Breakthrough Initiatives, a suite of space science programs investigating the fundamental questions of life in the Universe. These philanthropic initiatives are funded by the Breakthrough Foundation, established by Yuri Milner and his wife Julia.

Research Report: "Relativistic Light Sails Need to Billow"

Related Links
University of Pennsylvania
Space Tourism, Space Transport and Space Exploration News

Thanks for being there;
We need your help. The SpaceDaily news network continues to grow but revenues have never been harder to maintain.

With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords.

Our news coverage takes time and effort to publish 365 days a year.

If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.
SpaceDaily Monthly Supporter
$5+ Billed Monthly

paypal only
SpaceDaily Contributor
$5 Billed Once

credit card or paypal

NASA Solar Sail Mission to Chase Tiny Asteroid After Artemis I Launch
Washington DC (SPX) Jan 21, 2022
NEA Scout will visit an asteroid estimated to be smaller than a school bus - the smallest asteroid ever to be studied by a spacecraft. Launching with the Artemis I uncrewed test flight, NASA's shoebox-size Near-Earth Asteroid Scout will chase down what will become the smallest asteroid ever to be visited by a spacecraft. It will get there by unfurling a solar sail to harness solar radiation for propulsion, making this the agency's first deep space mission of its kind. The target is 2020 GE, ... read more

Comment using your Disqus, Facebook, Google or Twitter login.

Share this article via these popular social media networks
del.icio.usdel.icio.us DiggDigg RedditReddit GoogleGoogle

Ukraine crisis challenges International Space Station cooperation

Coca-Cola launching new Starlight drink 'inspired by space'

Blue Origin to build more rockets amid expectations to tourist flights

How to design a sail that won't tear or melt on an interstellar voyage

Rocket Lab officially opens third launch pad, Next launch within a week

Clean driving technology enables cleaner rocket fuel

SpaceX successfully launches 46 Starlink satellites from Florida

Vaya Space completes first suborbital test flight

NASA's Perseverance celebrates first year on Mars by learning to run

Caution! Martian wind at work

Rocky Road offers plenty of tasty science bites during Sols 3391-3394

Sol 3395: Last Chance for Contact

China to make 6 human spaceflights, rocket's maiden flight in 2022: blue book

China welcomes cooperation on space endeavors

China Focus: China to explore lunar polar regions, mulling human landing: white paper

China to boost satellite services, space technology application: white paper

SpaceX to launch IoT tech demo satellites for Plan-S

Scottish Space Sector Charts Path to a Sustainable Future

Whitepaper highlights ground segment's critical role in satellite connectivity

Space sector set to create new jobs in Highland and Moray

Northrop Grumman awarded US Space Force contract for deep-space advanced radar

China denies making space junk set to crash into Moon

NRAO and Optisys Partner Up to Produce 3D Devices for Radio Astronomy

SpaceX to launch SpaceLogistics Mission Extension Pod for Optus satellite

'Tatooine-like' exoplanet spotted by ground-based telescope

Can a planet have a mind of its own?

Day of Discovery: 7 Earth-Size Planets

Studying the next interstellar interloper with Webb

New Horizons team puts names to the places on Arrokoth

NASA Telescope Spots Highest-Energy Light Ever Detected From Jupiter

Juno and Hubble data reveal electromagnetic 'tug-of-war' lights up Jupiter's upper atmosphere

Oxygen ions in Jupiter's innermost radiation belts

The content herein, unless otherwise known to be public domain, are Copyright 1995-2024 - Space Media Network. All websites are published in Australia and are solely subject to Australian law and governed by Fair Use principals for news reporting and research purposes. AFP, UPI and IANS news wire stories are copyright Agence France-Presse, United Press International and Indo-Asia News Service. ESA news reports are copyright European Space Agency. All NASA sourced material is public domain. Additional copyrights may apply in whole or part to other bona fide parties. All articles labeled "by Staff Writers" include reports supplied to Space Media Network by industry news wires, PR agencies, corporate press officers and the like. Such articles are individually curated and edited by Space Media Network staff on the basis of the report's information value to our industry and professional readership. Advertising does not imply endorsement, agreement or approval of any opinions, statements or information provided by Space Media Network on any Web page published or hosted by Space Media Network. General Data Protection Regulation (GDPR) Statement Our advertisers use various cookies and the like to deliver the best ad banner available at one time. All network advertising suppliers have GDPR policies (Legitimate Interest) that conform with EU regulations for data collection. By using our websites you consent to cookie based advertising. If you do not agree with this then you must stop using the websites from May 25, 2018. Privacy Statement. Additional information can be found here at About Us.