As humanity has grown it has expanded to fit its needs. In this day and age, humankind has started consuming resources at an alarming rate and has stopped exploring new places to compensate for the rate of consumption. As humanities population continues to grow, the Earth will be unable to support all of the population, and the only place to go is space. Space travel will help humanity better deal with decreasing natural resources and an increasing population.

Humanity as a race has been steadily growing in population for a very long time. However, the growth of the population has become greater than what the planet can compensate for. In 1950 the population of the world was 2,525,778,669, and grew to 4,071,020,434 in 25 years. In contrast, the population grew from 4,449,048,798 in 1980 to 6,051,478,010 in 1999. What once took the world 25 years to have the population grow by 2 billion people now takes 20.(geohive) This is troubling as humanity had gone into ecological debt in 2015 after only 8 months. Weather offers a reason  “The group estimates that it takes the equivalent of 1.6 Earths to support the world's population of more than 7 billion today, a number that's expected to grow to more than 9 billion by 2050” Further more, there are estimates that state that the current trends in population growth will require 2 Earths to sustain humanity. To make such an outrageous claim become reasonable, humanity will have to look outward to the stars if it wants to survive. With the resources on Earth dwindling, and humanity “will be living on resources borrowed from future generations,” As a result, turning to something outside of Earth is the obvious way to acquire resources. The closest would be the asteroids surrounding the interior planets of Mercury, Venus, Earth, and Mars. As the National Space Society states “Immediate uses of these resources to manufacture propellants, structural metals, refractories, life-support fluids and glass can support future large-scale space activities.” (nss) In addition to the resources supporting future space activities, they could also be used on Earth to assist in limiting the strain the population puts on Earth. By exploring space and using the resources near Earth already, humanity can help alleviate the strain put onto the planet and offer more land for inhabitation.

As resources dwindle on Earth, much of the moon and the surrounding areas are unexplored. In regards to the Moon, most of the landings took place near the equator and the gathering and testing of the lunar materials does not go past a small area of the landing zone. The National Space Society states “Although Earth-based multispectral mapping has continued to improve since the Apollo era, we still do not have direct chemical data on most of the Moon's surface. Thus the task begun by Apollo, to carry out complete geochemical mapping of the Moon, remains as unfinished business.” This is a mistake as the the resources on the moon could help sustain life on the moon, which could eventually evolve into a hub for even more space travel. The lunar resources appear to be radiation resistant and could be used for thermal isolation and heat storage in the initial stages of lunar landings and base building. The National Space Society further believes that eventually the biggest resource the Moon would yield is the “manufacture of rocket propellants...it may be possible to export lunar-produced oxygen from the Moon to low Earth orbit, where it might be economically attractive to use it as propellant in support of lunar resupply operations or even missions to Mars.” Furthermore, there are many deposits of other resources from comets and meteors that have hit the Moon, trapping resources like sulfur and potassium. By using the resources found on the Moon, it would be reasonable for humanity to take advantage of the minerals on Near Earth Asteroids. Due to the various raw materials inside of the asteroids make trips to the the celestial bodies very productive. While the predicted Mass Payback Ratio for the Moon is estimated at 0.1, and eventually increasing to 2.4 after return trips. For various asteroids, the MPBR is estimated to be at around 6 and after return trips and technological advances, a MPBR of around 100:1. While this is in part due to the fact that the missions to the asteroids would be simple mineral retrieval instead of trying to make a permanent residence like the Moon. According to the N.S.S, the Near Earth Asteroids will yield “very large masses of non terrestrial raw materials, such as metals or carbonaceous asteroid material...These materials can then be processed into SPS construction members, propellants, life-support fluids, glasses, ceramics (for heat shields), and radiation shielding.” These resources will help expand space travel even more in addition to giving more resources back to Earth. By doing so and with such high payback ratios, Space travel will not only become self sustaining, it will also better help with resource shortages on Earth.

In order for humanity to survive in the next millennia, it will have to expand and reach for the stars. Not only will this help with the resource consumption of humans, but it will also help to house the increasing population. By exploring space, humanity will be able to handle many challenges