The nearest star to our sun is Proxima Centauri, about 4.2 light-years away. That sounds manageable until you translate it: 40 trillion kilometres. Our fastest spacecraft, the Voyager 1 probe, travels at roughly 60,000 km/h. At that speed, it would take about 70,000 years to get there. We need a better plan.
The problem with distance
Space is almost incomprehensibly empty and large. The distances between stars are measured in light-years — the distance light travels in a year — and light is the fastest thing in the universe. Even travelling at a significant fraction of light speed would take years or decades to reach the nearest stars. For more distant ones, centuries or millennia.
Imagine the sun is a football on a pitch in London. On that scale, the nearest star would be another football sitting in Paris. The entire solar system — all the planets, the asteroid belt, everything — would be about the size of the centre circle. The distances between stars make the distances between planets look like stepping stones.
Idea 1: Generation ships
One proposal accepts the timescale problem: build a ship large enough to house hundreds of people, who live and die on board across multiple generations during the journey. The great-great-great-grandchildren of the original crew would eventually arrive. This would be an extraordinary feat of engineering, sociology, and self-contained life support — essentially building a travelling colony.
Idea 2: Laser-propelled light sails
The Breakthrough Starshot project, backed by Stephen Hawking before his death, proposed firing a powerful laser at a tiny spacecraft with a reflective sail. The light pressure could accelerate it to 20% of the speed of light — fast enough to reach Proxima Centauri in about 20 years. The catch: the spacecraft would be roughly the size of a postage stamp. Getting useful data back would be the challenge.
Idea 3: Suspended animation
Science fiction loves this one — putting the crew in a kind of deep sleep so they don't age (or get bored) during a long journey. There's no technology to do this yet, but research into inducing hibernation-like states in humans is genuinely underway, driven partly by medical applications like preserving patients during surgery.
Will it ever happen?
Not in the next century, almost certainly. But given that humans went from the first powered flight to landing on the moon in 66 years, projecting technological limits over thousands of years seems unwise. The real barriers — energy, materials, biology — are enormous. But they're physics problems, not magic. And physicists have a good record.
The nearest star to our Sun is called Proxima Centauri. It is about 4.2 light-years away. That might not sound too bad. But in kilometres, that is 40 trillion kilometres. Our fastest spacecraft is called Voyager 1. It travels at about 60,000 kilometres per hour. At that speed, it would take 70,000 years to get there. We definitely need a better idea.
The problem with distance
Space is almost impossibly big and empty. The gaps between stars are measured in light-years. A light-year is how far light travels in one whole year. Light is the fastest thing in the universe. Even travelling at a big fraction of light speed would take years to reach nearby stars. Reaching farther stars would take hundreds or thousands of years.
Imagine the Sun is a football on a pitch in London. On that same scale, the nearest star would be another football sitting all the way in Paris. The whole solar system — all the planets and everything else — would only be as big as the centre circle. Compared to the gaps between stars, the gaps between planets are like tiny steps.
Idea 1: Generation ships
One idea accepts that the journey will take a very long time. Scientists suggest building an enormous ship. It would carry hundreds of people living their whole lives on board. Those people would have children, and their children would have children too. Eventually, the great-great-great-grandchildren of the first crew would arrive at the star. Building this ship would be incredibly difficult. It would be like creating a whole moving town in space.
Idea 2: Laser-propelled light sails
A project called Breakthrough Starshot had the support of the famous scientist Stephen Hawking. The idea is to fire a powerful laser beam at a tiny spacecraft. The spacecraft would have a very thin, shiny sail. The push from the laser light could speed it up to 20 percent of the speed of light. At that speed, it could reach Proxima Centauri in about 20 years. However, the spacecraft would only be roughly the size of a postage stamp. Sending back useful information from so far away would be very hard.
Idea 3: Suspended animation
This idea appears in lots of films and stories. The crew would be put into a very deep sleep for the whole journey. They would not age or get bored while they slept. We do not have the technology to do this yet. But scientists are genuinely researching ways to put humans into a hibernation-like state. Some of this research is already being used to help patients during difficult medical operations.
Will it ever happen?
Almost certainly not within the next hundred years. But think about this. Humans went from the very first powered aeroplane flight to landing on the Moon in just 66 years. It seems unwise to say something is impossible over thousands of years. The real problems are things like energy, materials, and keeping humans healthy. These are enormous challenges. But they are science and engineering problems, not impossible magic. And scientists have an excellent record of solving hard problems.