Laser-Based Propulsion System Could Get Us to Mars in Record Time—Just Three Days

This could open allow for the exploration of nearby exoplanets, solar systems, and other parts of the galaxy. 


Artist conceptualization of Breakthrough Starshot
Artist’s rendition of a solar sail on the announcement of Breakthrough Starshot.

Scientists are gearing up for further explorations into space. But normal rockets aren’t going to cut it for missions to places like Mars and beyond. With conventional rocketry, we can make it to the red planet in five months’ time, at its closest point to Earth. Photonic propulsion could be the answer, according to NASA scientist Philip Lubin. He’s a professor of physics at the University of California, Santa Barbara.  

Lubin explains his concept in a recent video for NASA 360. He and his team were awarded a NASA Innovative Advanced Concepts (NIAC) grant of $100,000 to outline a roadmap and conduct initial testing. The project is dubbed: Directed Energy Propulsion for Interstellar Exploration (DEEP-IN). Using this method, an unmanned probe could make it to Mars in about three days’ time, at the red planet’s closest point. The plan calls for placing a laser in Earth’s orbit. It could serve another purpose as well, as a defense system, protecting our planet from asteroids.

For propulsion, the system uses a solar sail pushed by the laser. A solar sail is what it sounds like—a thin, lightweight material which fills with photons or light particles reflected off of any surface, and catches them, much like a normal sail catches wind, causing propulsion. There have been two successful tests of such a sail, the IKAROS mission conducted by Japan’s JAXA space agency in 2010, and another by NASA in 2011.  

A solar sail. By NASA/Marshall Space Flight Center [Public domain], via Wikimedia Commons.

Without the need to carry fuel, spacecraft would be far lighter and travel faster for longer periods, allowing such a craft to reach relativistic speeds, or that which is significant relative to the speed of light. According to Einstein, time would move more slowly for those aboard such a vessel. The closer to the speed of light one comes, the slower time appears.

So how fast would it travel? A wafer-thin probe could move at 30% the speed of light, an “unheard of” velocity, according to NASA scientists. Voyager 1 is currently traveling at 0.006 percent the speed of light, just for comparison. Lubin wrote in a separate paper that, "Electromagnetic acceleration is only limited by the speed of light while chemical systems are limited to the energy of chemical processes."

The whole project sounds like science fiction right? But Lubin says that the technology already exists, it just needs to be scaled up. That’s important because the first real mission to Mars is planned for 2030. According to Lubin, a 100 kilogram (220 lb.) unmanned robotic spacecraft could make it there in just three days. A manned one would take longer, about a month or so, four months shorter than by current means.

But Mars is just the beginning. Such technology could open up new possibilities for space exploration. At an NIAC symposium in 2015 Lubin said, "Within about 25 light-years of the Earth, there are actually quite a few potential exoplanets and habitable things to visit." For example, Alpha Centauri is the closest solar system, over four light years away. But according to Lubin, a small probe using photonic propulsion could make it in about 17 years.  

This tech is earmarked for small, unmanned spacecraft. Sending AI throughout the galaxy would garner enormous benefits. We could even find other inhabitable worlds. Despite this, there are still significant challenges to overcome. For instance, how would we beam the information back? Communicating with Earth would pose a daunting challenge. Another issue is employing a laser strong enough, and finding ways of slowing the probe down once it reached its destination.

Artist’s depiction of Proxima Centauri b (Proxima b), an exoplanet in the inhabitable zone of the star Proxima Centauri, theoretically reachable using photonic propulsion.  

Besides photonic propulsion, other models are in the works. One that has gotten a lot of press lately, the EM Drive, is an electromagnetic acceleration system whose initial test was successful. Yet, no one quite understands how it works. Another is an antimatter rocket, proposed by Positron Dynamics CEO Ryan Weed. Weed, speaking with Wired last year, said such a rocket could “loop the Earth in three seconds.” We could also reach Mars in weeks’ time, rather than months.

This system uses positrons and electrons. When they interact, it causes propulsion at a velocity of 72 million mph (approx. 116 mil. kmh), the CEO said. Meanwhile, NASA’s current ion thrusters have a top speed of just 200,000 mph (approx. 322,000 kmh). The cost however is prohibitive, about £12,500 per kilogram (approx. $15,000 per 2.2 lbs.).

We understand photonic propulsion, at least theoretically. And it isn’t so expensive, although it may require a ring of superconducting magnets, like those used in a Large Hadron Collider. Those aren’t cheap. Even so, Lubin’s plan can be developed in a cost-effective manner. So as it stands now, laser-based solar sails are likely to provide humanity’s next evolutionary step, exploring more our solar system, nearby exoplanets and in decades and centuries to come, more of our Milky Way.

To see the NASA video for yourself, click here: 

Massive 'Darth Vader' isopod found lurking in the Indian Ocean

The father of all giant sea bugs was recently discovered off the coast of Java.

A close up of Bathynomus raksasa

SJADE 2018
Surprising Science
  • A new species of isopod with a resemblance to a certain Sith lord was just discovered.
  • It is the first known giant isopod from the Indian Ocean.
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Volcanoes to power bitcoin mining in El Salvador

The first nation to make bitcoin legal tender will use geothermal energy to mine it.

Credit: Aaron Thomas via Unsplash
Technology & Innovation

This article was originally published on our sister site, Freethink.

In June 2021, El Salvador became the first nation in the world to make bitcoin legal tender. Soon after, President Nayib Bukele instructed a state-owned power company to provide bitcoin mining facilities with cheap, clean energy — harnessed from the country's volcanoes.

The challenge: Bitcoin is a cryptocurrency, a digital form of money and a payment system. Crypto has several advantages over physical dollars and cents — it's incredibly difficult to counterfeit, and transactions are more secure — but it also has a major downside.

Crypto transactions are recorded and new coins are added into circulation through a process called mining.

Crypto mining involves computers solving incredibly difficult mathematical puzzles. It is also incredibly energy-intensive — Cambridge University researchers estimate that bitcoin mining alone consumes more electricity every year than Argentina.

Most of that electricity is generated by carbon-emitting fossil fuels. As it stands, bitcoin mining produces an estimated 36.95 megatons of CO2 annually.

A world first: On June 9, El Salvador became the first nation to make bitcoin legal tender, meaning businesses have to accept it as payment and citizens can use it to pay taxes.

Less than a day later, Bukele tweeted that he'd instructed a state-owned geothermal electric company to put together a plan to provide bitcoin mining facilities with "very cheap, 100% clean, 100% renewable, 0 emissions energy."

Geothermal electricity is produced by capturing heat from the Earth itself. In El Salvador, that heat comes from volcanoes, and an estimated two-thirds of their energy potential is currently untapped.

Why it matters: El Salvador's decision to make bitcoin legal tender could be a win for both the crypto and the nation itself.

"(W)hat it does for bitcoin is further legitimizes its status as a potential reserve asset for sovereign and super sovereign entities," Greg King, CEO of crypto asset management firm Osprey Funds, told CBS News of the legislation.

Meanwhile, El Salvador is one of the poorest nations in North America, and bitcoin miners — the people who own and operate the computers doing the mining — receive bitcoins as a reward for their efforts.

"This is going to evolve fast!"

If El Salvador begins operating bitcoin mining facilities powered by clean, cheap geothermal energy, it could become a global hub for mining — and receive a much-needed economic boost in the process.

The next steps: It remains to be seen whether Salvadorans will fully embrace bitcoin — which is notoriously volatile — or continue business-as-usual with the nation's other legal tender, the U.S. dollar.

Only time will tell if Bukele's plan for volcano-powered bitcoin mining facilities comes to fruition, too — but based on the speed of things so far, we won't have to wait long to find out.

Less than three hours after tweeting about the idea, Bukele followed up with another tweet claiming that the nation's geothermal energy company had already dug a new well and was designing a "mining hub" around it.

"This is going to evolve fast!" the president promised.

How Pfizer and BioNTech made history with their vaccine

How were mRNA vaccines developed? Pfizer's Dr Bill Gruber explains the science behind this record-breaking achievement and how it was developed without compromising safety.

How Pfizer and BioNTech made history with their vaccine
Sponsored by Pfizer
  • Wondering how Pfizer and partner BioNTech developed a COVID-19 vaccine in record time without compromising safety? Dr Bill Gruber, SVP of Pfizer Vaccine Clinical Research and Development, explains the process from start to finish.
  • "I told my team, at first we were inspired by hope and now we're inspired by reality," Dr Gruber said. "If you bring critical science together, talented team members together, government, academia, industry, public health officials—you can achieve what was previously the unachievable."
  • The Pfizer-BioNTech COVID-19 Vaccine has not been approved or licensed by the Food and Drug Administration (FDA), but has been authorized for emergency use by FDA under an Emergency Use Authorization (EUA) to prevent COVID-19 for use in individuals 12 years of age and older. The emergency use of this product is only authorized for the duration of the emergency declaration unless ended sooner. See Fact Sheet:

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