With our species blessed with 83 worlds that orbit our home star, why would we choose to settle some and skip the rest? After all, would it not be in humanities best interest to spread our glory over every celestial moon, planet and dwarf planet?
While covering every centimeter of every orbiting sphere may sound glorious, it may not be practical (or even desired) by our future descendants. Just as the human race chooses to (mainly) live within fertile valley’s and hills over deserts and mountains, so to our children may opt to skip worlds with “too much hassle” involved in settling them.
A prime example of this would be Mercury. Although humanity may posses the capability of colonizing this sphere, its close orbit towards the Sun may make it uninhabitable, at least during the day time (thanks to solar radiation).
Even though Mercury may contain many precious metals beneath its baked crust, it will probably never boast large metropolis’s upon its surface, unless Earth decides to turn it into a planetary penal colony.
Moving outward to Venus, one could easily realize why humanity would never ever want to set foot on the planet, let alone through its thick atmosphere. The atmospheric pressure on Venus is about 90 times that of Earth, strong enough to crush a human unprotected.
Hosting sulfuric acid within its upper clouds, Venus may be more valuable as an interplanetary garbage dump than a viable colony (even for science).
Over in the Jovian system, Jupiter’s moon Io shares a similar fate to Venus. Although lacking an atmosphere, Io does house numerous volcanoes upon its surface, some of which spew hot sulfur hundreds of kilometers from its surface.
Even if scientists were able to withstand the deadly radiation that engulfs this world, they would probably not enjoy swimming in one of Io’s numerous lava lakes.
Despite the fact that Io’s lunar sister is known to harbor an abundance of water ice, Europa may only gather a mournful glance from a few scientists observing from Ganymede. Even though many scientists suspect that Europa may have oceans beneath its surface, the world is jealously guarded by its father Jupiter, who bathes its lunar daughter in deadly radiation.
While some have suggested digging a hole beneath the icy surface, doing so may only guarantee ones fate within the icy walls, as Europa has a fairly active surface, which could result in one getting crushed by its icy “tectonic plates.”
When it comes to radiation, Saturn’s ring worlds do not seem to fare any better than Europa. While the icy moons of Mimas, Enceladus, Tethys, Dione, and Rhea may find their surfaces scoured by robots (in search of water ice), these lunar bodies unfortunately orbit within Saturn’s radiation belts.
Even though engineers will probably find a way to shield themselves with artificial magnetic fields (or even create enormous planetary versions), the added cost of doing so may make living on these worlds too expensive for the “average space colonist.”
The moons of Uranus and Neptune who dance around their green and blue parents, respectively may share a similar fate to their Saturian cousins.
Although its quite possible that these moons may eventually be settled by humanity, they may find themselves harboring space pirates (to the delight of solar governments everywhere) as their distance from Earth and lack of nearby resources may make them unattractive for the masses.
Heading out towards the Kuiper belt, one wonders whether humanity will have the attention span of settling any of these frozen objects at the edge of our solar system.
Although colonizing both Pluto and Charon could provide a few engineering delights, one wonders if humanity may simply decide to ignore these historical relics as they head out to other promising star systems.