The vastness of the universe is beyond our imagination. Space travel has always fascinated us and we have been exploring different aspects of space science to unravel its mysteries. As humans, we are now aware that many stars and planets lie beyond our solar system, in fact, they are distributed throughout the Milky Way galaxy which itself stretches over a distance of around 100,000 light years. This article will explore how long it takes to travel 100 light years within our current understanding of physics.

What is a Light Year?

What is a Light Year?

Before diving into the topic on how long it would take to travel 100 light years, let’s first understand what exactly a ‘light year’ means. A light year is defined as the distance traveled by light in one Earth calendar year, at approximately 186,282 miles per second (299792 km/sec). It measures both time and distance; one light-year represents about six trillion miles or nine trillion kilometers.

How fast can Humans Travel Within Our Solar System?

Before discussing interstellar travel outside our solar system let us examine how quickly humans can move within it? In today’s world astronauts aboard International Space Station (ISS) travels at around 17,500 mph (28 thousand km/h), curious young minds might wonder whether this speed could be enough for interstellar travel? However traveling through space does not work like driving on earth highways since there are no limitations there from friction or air resistance rather space-crafts must push against any gravitational pull tugging them toward Earth while their thrusters pull towards deep space.

Interstellar Travel:

Many factors need considerations when traveling into deep space including distance from the starting point even if just moving to another planet (Mars) would require detailed planning such as fuel consumption i.e velocity needed for launch big enough vehicle (& also with significant life support facilities), communication systems & obviously proficient astronauts who also understand dangers associated with prolonged periods in zero-gravity situations.

NASA recently released its groundbreaking mission report titled ‘The Interstellar Probe to the Heliosphere and Beyond’. According to this, an interstellar probe traveling at a constant velocity of 10% to 20% the speed of light i.e about 18,641-37,282 miles per second (30 -60k km/s), could potentially travel around a distance range between ten or twenty light years in merely decades. What seems like quick progress is only within our limited understanding of physics since any breakthrough will require technologies beyond current human capability.

How Long Would It Take To Travel 100 Light Years?

When considering how long it would take to travel a hundred light-years various factors come into play including for instance physical barriers outside our solar system such as planets or asteroids in space often present risks when taking spacecraft so from landing possible damages can be avoided.

Currently, NASA’s Parker Solar Probe is on-route towards Alpha Centauri system which has picked up further interest by scientists given its close proximity. Named Proxima Centauri, it lies approximately four star-systems away from the Sun. The distance seems minuscule compared with other stars however at just over three trillion miles (~4.3 trillion kilometers) away from Earth it still takes roughly over four years (approximately 52 months) for even EM radiation ie visible light wavelengths used in modern-day communication platforms via antennae installed on Deep Space Network-equipped vessels (used by SpaceX’s Falcon Heavy missions among others) so time delay needs consideration before broadcasting information back home if humans were ever able successful launch for that far-end journey.

Even given science fiction aspirations humanity faces realities of deep space-travel & while much research undertaken not until we learn more about quantum mechanics than true intergalactic trips feasible within foreseeable future owing also both challenges technological limitations ethical aspects concerning effect venturing out into something beyond what know exist today without knowing potential outcomes implications consequences down line return safely again ultimately completing the mission successfully.


In conclusion, interstellar travel is still an enigma for humans. There have been many leaps and bounds in human understanding of space-science but not all aspects are fully understood yet. As more knowledge pours forth from scientists working on projects to study deep space further, we can possibly work out ways to achieve long-distance interstellar exploration without compromising safety concerns or technological limitations while keeping ethical factors into consideration at every step along the way until then closest answers in form robotic exploratory missions will probably remain best route use what too offer learn discover unlock secrets universe possesses beyond our galaxy!