Scientists say that even if you travel at the speed of light, you still can't reach the edge of the universe?

The universe is vast with mysteries beyond human understanding, from the vast Solar System to distant galaxies billions of light years away. Although the speed of light is considered the fastest, but before the constant expansion of the universe, the journey of discovery still seems like a distant dream.

The vast universe has always been one of the most fascinating mysteries that humanity has tried to explore. Since the first days of observing the sky, we have gradually realized that the space we live in is just a small part of the Solar System, the Milky Way, and the entire infinite universe. However, this journey of discovery also means that we have to face the incredible limitations of current science and technology.

The Solar System: Bigger Than We Think

The vast universe has always been one of the most fascinating mysteries that mankind has tried to explore.

Take Voyager 1, one of humanity's two iconic spacecraft. Launched in 1977, Voyager 1 has been hurtling through space for more than 40 years and is now about 24 billion kilometers from Earth. This distance may seem incredible, but in reality, it is just a small step on the journey out of the Solar System. According to scientists , the edge of the Solar System is defined by the Oort cloud – a vast region of icy objects about 1 light-year from Earth . This means that even if Voyager 1 could maintain its current speed, it would take tens of thousands of years to reach the edge of the Solar System.

If we had a spacecraft that could travel at the speed of light – 300,000km/s – the journey out of the Solar System would still take at least a year, demonstrating that even with technology far beyond our current capabilities, exploring the Solar System is a huge challenge.

Distance to neighboring stars

The nearest star system to us, Proxima Centauri, is about 4.22 light years away. If we could travel at the speed of light, the journey would take just over four years. Meanwhile, to escape the Milky Way would take a journey of 3,000 years . And to reach the nearest galaxy – the Andromeda Galaxy – the estimated time is 2.54 million years.

These numbers not only show the vastness of the universe, but also highlight the limits of current technology. Even the speed of light , the fastest speed known to man, is not enough to explore every corner of space.

The Observable Universe: An Unsurpassable Limit?

According to scientists, the observable universe is currently about 93 billion light years in diameter. This means that, even if we could travel at the speed of light, the journey from one end of the universe to the other would take at least 93 billion years. However, the reality is more complicated than that . The universe is not only vast, but it is also constantly expanding, causing distant objects to move farther and farther away from us.

The universe is not only vast, it is also constantly expanding.

The expansion of the universe was first discovered by astronomer Edwin Hubble in 1929. He noticed that distant galaxies were redshifted, a phenomenon that indicated that they were moving away from Earth. Space is constantly expanding, and this expansion rate can even exceed the speed of light at certain distances . This does not violate Einstein's theory of relativity because it is the expansion of space-time itself, not the movement of objects in space.

According to data from the European Space Agency's Planck satellite, the current expansion rate of the universe is about 67 kilometers per second per million parsecs (3.26 million light years). At a distance of 14.5 billion light years, the expansion rate has exceeded the speed of light. And at 93 billion light years, the expansion rate is many times greater than the speed of light. Therefore, any galaxy more than 93 billion light years away is invisible to us, because the light from it can never reach Earth.

Limit of the speed of light

Although the speed of light is considered the ultimate limit in the universe, it is powerless against the ever-increasing expansion of space . The existence of dark energy – the force driving the expansion of the universe – makes the edge of the universe an unreachable goal.

A theoretical solution to this limitation is to use wormholes or warp drives, which were proposed in Einstein's theory of relativity. These concepts do not require exceeding the speed of light but rather change the structure of space-time, allowing for shortening distances in space or creating shortcuts between distant points. However, these are still hypothetical and there is no practical technology that can make them a reality.

The existence of dark energy makes the edge of the universe an unreachable target.

The Future of Space Exploration

Perhaps, in millions or hundreds of millions of years, humans will find a way to overcome the current barriers. But at this time, the universe is still a vast space with countless mysteries beyond our reach. The journey of discovery requires not only great advances in technology but also the perseverance and endless passion of mankind.

The universe is a place that holds not only the big questions but also the dreams of human existence. Every step forward, no matter how small, brings new insights, inspires us, and pushes us further in our space exploration. While we wait for breakthroughs, we can be proud of what we have achieved and continue to dream of the endless possibilities that lie ahead.