Newly discovered exoplanets, some similar in size to Earth and relatively close to us, fuel dreams of space exploration and potential colonization. Yet, the vast distances between stars remain a daunting obstacle, leaving such endeavors in the realm of fantasy for now.

According to NASA's Exoplanet Archive, there are currently 4,126 confirmed exoplanets outside our solar system. Just a few decades ago, we were aware of only the planets within our own solar neighborhood. A significant breakthrough in our understanding has revealed that planets orbiting stars is quite common, and some of these planets exist in the habitable zone, where liquid water could potentially exist.

Notably, in 2017, astronomers identified a system of seven planets orbiting the red dwarf star TRAPPIST-1. Utilizing data from the Hubble and Spitzer space telescopes, researchers found that three of these planets are within the habitable zone and likely possess rocky surfaces similar to Earth. These planets may have atmospheres that could support liquid water and possibly life.

Such exciting findings have not gone unnoticed in popular culture. Media coverage has sparked imaginations about the possibility of exploring or colonizing these planets, especially if Earth were to become uninhabitable. The idea of constructing vast spaceships to carry millions of pioneers to TRAPPIST-1, which is approximately 40 light-years away, has captivated many.

However, enthusiasts of interstellar travel often underestimate the true scale of these distances. Even if one of these seven planets turned out to be a perfect Earth replica, the sheer distance means that sending a robotic probe for exploration remains firmly in the domain of science fiction.

The most accurate current measurement of TRAPPIST-1's distance comes from the astrometric satellite Gaia, which places it at 40.54 light-years away. For context, the New Horizons spacecraft, which reached Pluto in nine years, would take around 870,000 years to reach TRAPPIST-1, highlighting the impracticality of mass migration to these distant worlds.

While future technological advancements may one day overcome some of these limitations, fundamental physical constraints, such as the effects of time dilation, will still pose challenges. Explorers sent on a mission to gather information about colonizable planets may return to find Earth transformed, having experienced a significant time lag relative to those left behind.

Envisioning the timeline of multiple missions to establish a self-sustaining human colony on an exoplanet reveals the daunting nature of such an endeavor. The notion of mass migration appears to be nothing more than a concept for the future, as even colonizing Mars presents challenges that push the limits of our current capabilities.

Nonetheless, the idea of commercial aerospace companies offering affordable interstellar flights is a tantalizing dream. Human perceptions often fail to grasp the true vastness of space. While the distance of 40 light-years may seem manageable, converting it to kilometers reveals a staggering 383 trillion kilometers—a number far beyond our everyday comprehension.

To foster a better understanding of these astronomical distances, one must start with smaller scales, such as our solar system. However, even this familiar context proves difficult to visualize accurately.

Bill Bryson aptly illustrates this in his book, A Short History of Nearly Everything, noting that creating a scale model of the solar system is nearly impossible. For instance, if Earth were the size of a pea, Jupiter would be over a thousand feet away, and our nearest star, Proxima Centauri, would be nearly ten thousand miles distant.

One creative attempt to visualize these distances involved a project in the Nevada Desert, where marbles and balloons represent the solar system. However, even this project fails to convey the vastness of space effectively.

A more impactful representation was created by artist Josh Worth, who developed a web page to illustrate the distances within our solar system. By scaling the moon to one pixel, users can scroll through the solar system, emphasizing the immense space between celestial bodies.

Josh Worth's project, titled If the Moon were only 1 pixel, provides a compelling way to comprehend the vastness of the solar system. Users can manually scroll from the Sun to Pluto, experiencing firsthand the vast distances involved.

Upon reaching Pluto, users realize they are 328.5 light-minutes from the Sun—an incredible distance that underscores how far one must travel to reach the TRAPPIST-1 system, which is still 40.54 light-years away.

Ultimately, space is mostly empty, with celestial bodies scattered like dust in a vast void. This sparseness allows galaxies to collide without the stars within them posing a significant risk to one another.

In conclusion, while the dream of cheap interstellar travel is enticing, the reality of astronomical distances and the physical constraints of space travel remind us that such aspirations remain, for now, firmly in the realm of science fiction.