A new method of moving through space will allow us to reach the nearest star not in thousands of years, but in just a few decades.
Physicists have proposed a new way to deliver spacecraft to nearby stars in a relatively short time using relativistic electron beams. The study was published in the journal Acta Astronautica.
Without better space travel, dreams of reaching even the nearest stars may remain just dreams. The closest star to us, Proxima Centauri, is about 4 light years away. It is orbited by a potentially habitable planet, Proxima Centauri b. To study both the planet and the star up close, a space probe would have to be sent there.
If this probe traveled at the speed of, say, the most remote human spacecraft, Voyager 1, the journey would take more than 70,000 years.
There are now ideas to send spacecraft to the stars at relatively high speeds, equipped with a light sail and a laser beam. This beam must push the sail and allow the probe to reach very high speeds to move through space.
But such projects assume that the spacecraft’s size and weight will be small, meaning it can’t fit many scientific instruments.
Therefore, such a probe cannot collect much valuable information about nearby stars and their planets. On the other hand, the cost of launching such a laser beam is quite high and such a beam will also dissipate over a large distance, which reduces its effectiveness.
Current designs, which rely on a lightsail and a laser beam, suggest that the beam can only effectively push the probe to a distance of 0.1 astronomical units, while the distance to Proxima Centauri is approximately 270,000 astronomical units.
Although even such a small distance should be enough to accelerate the spacecraft to a very high speed. But the laser beam, as already mentioned, will disappear and therefore there is no guarantee that the probe will reach the nearest star in a reasonable time.
Therefore, physicists have proposed using electron beams or beams of electrons that would be accelerated to relativistic speeds to move a large probe with a light sail. This is a speed close to the speed of light. In this way it would be possible to send a probe of much greater size and mass to the nearest stars.
According to physicists, such a beam will allow the probe to collect more energy and its speed could be up to 10% of the speed of light.
Electrons are relatively easy to accelerate to speeds close to the speed of light. And the scattering of the electron beam can be avoided using an effect well studied in particle accelerators.
Scientists’ calculations show that such a beam can push a space probe to a distance of 100 and even 1000 astronomical units. Thanks to the speed obtained, the probe will be able to reach the star Proxima Centauri in about 40 years.
But accelerating the electron beam to relativistic speeds and keeping it pointed straight at the probe is still a challenge that needs to be solved, physicists say.
To create such a beam requires a lot of energy, which is why scientists propose to place another spacecraft close to the Sun, which will orbit our star and create the necessary electron beam, which will be aimed at the probe heading towards the stars flies.
According to scientists, minimal improvements to existing technologies will allow humanity to reach the nearest stars quite quickly.
