To explain the rather obscure title; TRAPPIST-1e is an exoplanet around a red dwarf star about 39 light years away from Earth. It’s one of seven planets and of those seven, it is one of the three that sit within the habitable zone of the star.
Why do I bring this up?
Well, I have long dreamed that one day humans would become a multiplanetary species. To be fair; that title also includes Mars and any of the planets in our Solar System. Perhaps I should take it a step further; I have hoped for a long time that one day humans would become an interstellar species.
The distinction is worth noting, I think. It seems inevitable that humans will eventually expand to Mars. Most likely to the Moon first, but once a base is built there travel between planets in the Solar System becomes far easier.
The Moon’s gravity is 1.62 m/s/s. Earth’s gravity is 9.81 m/s/s.
That fact alone is enough to entice humans to settle the moon and use it as a base. With less gravity, there is far less thrust needed to leave the surface. Less thrust means less fuel and, most importantly for humans, less money.
(I’m going to take an aside here and point out that the escape velocity of a planet is actually independent of their gravity. In a sense. The equation for escape velocity is the square root of 2xGxM/R. M = mass, R = radius, and G = the gravitational constant. No where in the equation is the gravity of the planet. Though, as gravity is dependent on the mass of the object, you could argue that it still plays a part.)
The escape velocity of Earth is 11.19 km/s. The moons escape velocity is 2.38 km/s.
Basically, to inhabit the rest of the Solar System, humans must first inhabit the moon.
But what does this have to do with TRAPPIST-1e?
The fastest speed ever reached by a human-made object in space (the Parker Solar Probe) was 153 454 mph. To put that into metric, 246 960 kph.
At that pace it would take 1494167438.44 hours to reach the TRAPPIST system. Or 170 567.05 YEARS.
Clearly we need a faster way to travel.
However, once we inhabit the Solar System, it is safe to assume that our technology (and hopefully our cooperation) would have evolved to the point where we could even create a Dyson Sphere.
Put simply, a Dyson Sphere is a solar farm that surrounds a sun. Obviously we can’t completely cover the Sun, for one, it’s huge and for another, we kind of need the light to keep warming our planets as well as providing energy to the Sphere.
One of the most common proposals for a Dyson Sphere is a series of smaller satellites that continuously orbit the Sun, thus providing humanity with all the power it would ever need. That is the limiting fact; even the constant of the speed of light doesn’t limit us from reaching other solar systems. If we travelled at 0.2 the speed of light (a mere 59958491.6 m/s) we would reach TRAPPIST in 195 years.
Okay, that’s still not fantastic but it’s a damn sight better than 170 000.
It seems inevitable to me that one day we humans will leave our Solar System and head into interstellar space. Whether we head towards TRAPPIST-1e or Kepler-186b, we will reach out. It’s in our nature; it’s what we do.
But first we need to inhabit the rest of our Solar System and that is something that is possible today.
I won’t be alive to see that and that is a truly heartbreaking fact but I draw hope knowing that some day humans will most likely step onto a planets surface that isn’t under the warm yellow light of our Sun.