Why is interstellar travel impossible today?

Interstellar travel has long been a dream of mankind. With millions of light years between stars in the Milky Way, the question is when will humans be able to make this ambitious journey?

Since the dawn of civilization, space exploration has always been a great dream of mankind. Interstellar travel is not only a bold idea in science fiction works but also a serious scientific goal that many generations of scientists have been aiming for.

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Space exploration has always been a great dream of mankind.

However, in today's technological landscape, that dream remains a distant one. The enormous distances between stars in the Milky Way require breakthroughs in technology, energy sources, and the ability to survive in space. The question is whether humans can make this great journey in the near future, or will it take many more generations to make it a reality?

Interstellar space is so vast that it's hard to imagine. Even if we wanted to travel to the nearest star to Earth, Proxima Centauri , it's about 4.24 light years away, or more than 40 trillion kilometers. At the speed of today's spacecraft, it would take thousands of years to get there.

The Parker Solar Probe is currently the fastest spacecraft ever built, with a speed of over 600km/s. However, even at this speed, it would still take Parker 7,200 years to reach Proxima Centauri. This shows that, despite advances in technology, the current speed of spacecraft is still not enough for humans to make further journeys into space.

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Parker Solar Probe.

The question then becomes, how do we increase the speed of spacecraft? Even though current spacecraft like Voyager, New Horizons, or Parker have improved their speed over time, they still only travel at a few tens of kilometers per second, which is only a fraction of the speed needed for interstellar travel. To do that, humans need to increase the speed of spacecraft by thousands, even millions of times.

One of the most intriguing ideas in science fiction is the wormhole . These are theoretical 'shortcuts' that could bridge the enormous distances between stars and galaxies. The theory of wormholes stems from solutions to Einstein's equations of general relativity . If wormholes really existed and could be controlled, they could be an efficient way for humans to travel across vast expanses of space quickly without having to travel at superluminal speeds.

However, wormholes are still a hypothesis and there is no experimental evidence to prove their existence. Furthermore, even if they do exist, creating a stable and safe wormhole to travel through is an extremely big challenge. Currently, scientists are still studying the theory and physics of wormholes, but practical applications are probably still a long way off.

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Wormholes are thought to be able to shorten the enormous travel distances between stars and galaxies.

Even if humans figure out how to speed up their spacecraft or use wormholes to travel faster, there's still another very important problem: energy . An interstellar journey could take thousands of years. During that time, a spacecraft needs a steady, sustainable source of energy to keep it running.

Currently, most spacecraft rely on solar power to power their operations. This works well when the spacecraft is close to the Sun or similar power sources, but when it enters the dark, distant reaches of interstellar space, solar power becomes useless. Therefore, humans need to develop new, more efficient power sources that can sustain spacecraft for long periods of time without relying on sunlight.

Several new energy ideas have been proposed, including using nuclear power, antimatter power, or harvesting energy from planets and asteroids in space. However, these technologies are still in the development stage and are not yet ready for use on an interstellar journey.

Interstellar travel not only requires speed and energy, but also raises complex questions about astronaut survival. If a journey lasts thousands of years, the crew will face the problem of how to sustain life during that journey.

Living conditions in space are harsh. There is no air, no gravity, and cosmic radiation is a major threat to the health of astronauts. In addition, living in space for a long time also has negative effects on the human body , from loss of muscle mass to bone degeneration.

If a voyage lasts for generations , astronauts also face the problem of reproduction and population maintenance on board the spacecraft. Maintaining a vibrant and reproducible community on board for thousands of years is a challenge for which humans currently have no concrete solution.

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In space, living conditions are very harsh. (Illustration photo).

Although humans are still far from achieving interstellar travel, we have made significant progress in exploring the universe. From successful missions like Apollo that landed humans on the Moon, to probes like Voyager that left the Solar System, these achievements demonstrate humanity's ability to explore the distant mysteries of the universe.

The continued development of science and technology also brings hope for future breakthroughs. Scientists are working on new ideas for space engines, from ion propulsion to antimatter engines. If these technologies are successful, we could open new chapters in space exploration, shorten travel times and send humans to other planets and star systems.

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With perseverance and aspiration, humans can continue to go further on the journey of space exploration.

Although interstellar travel is not yet possible, that does not stop humans from dreaming and continuing to explore. The challenges of speed, energy, and survival still exist, but with the spirit of constant innovation and exploration, humans can achieve breakthroughs in the future.

Like Christopher Columbus discovering America, conquering the stars is a long and risky journey. However, with perseverance and ambition, humans can continue to go further, surpassing current limitations to open new chapters in the history of the universe.