Could Space Elevators be Feasible? Physicist Suggests Transformation into a ‘Spacefaring Civilization’

The pursuit of exploring and potentially colonizing outer space has sparked numerous ideas on how to achieve this goal. While the conventional method of using rockets for space launches is widely accepted, alternative methods such as the concept of a space elevator have been proposed.

A space elevator is essentially a cable that extends into space, allowing humans to ascend into orbit. This idea has gained support from industry experts as it offers a potential solution to the exorbitant costs associated with rocket launches. Alberto de la Torre, an assistant professor of physics at Northeastern, explains that current launch systems are expensive, with costs exceeding $10,000 per kilogram of payload and totaling around $60 million per launch. This is where space elevators become appealing.

The concept of a space elevator was first envisioned by Russian rocket scientist Konstantin Tsiolkovsky in the late 19th century. The elevator would extend from the ground through the atmosphere and beyond geostationary orbit, which is an altitude where objects in space orbit in sync with the Earth’s rotation due to gravity. Geostationary orbit is approximately 22,236 miles above the Earth’s surface.

The cable of the space elevator would be anchored to a satellite structure in geostationary orbit, acting as a counterweight that extends down to Earth. Theoretically, a satellite positioned beyond geostationary orbit would help stabilize the cable through a combination of forces. The Earth’s gravitational pull would exert a downward force on the cable from the ground, while the centrifugal force of the satellite’s rotation would exert an upward force on the cable from space. These forces would create the necessary tension to sustain a cable of such length.

In summary, the concept of a space elevator offers a potential alternative to traditional rocket launches, providing a more cost-effective and efficient means of sending humans and cargo into space.

According to de la Torre, the cable is the crucial component of a space elevator, which is positioned at the Earth’s equator and synchronized with its rotation.

Currently, there is no proof of concept for a space elevator. Despite various attempts at designing it, including a prize-winning design by a British architect, numerous technical challenges have prevented its realization for decades.

De la Torre explains that creating a cable of such length, more than 22,236 miles above the Earth, is not feasible with standard materials. If made of steel, the cable would face tension at geostationary orbit that exceeds its tensile strength rating by over 60 times.

To overcome this, reducing tensile forces is crucial for an Earth-based space elevator, according to de la Torre. He suggests that materials like boron nitride nanotubes, diamond nano threads, and graphene, which have low density and high tensile strengths, show promise.

De la Torre also mentions that carbon nanotubes are proposed as an ideal material due to their high tensile strength. However, recent research has raised concerns about translating their nano-scale properties to megastructures.

Ultimately, the space elevator holds the potential to significantly reduce the cost of space travel. De la Torre states that the expense of sending a payload beyond a geostationary orbit could be reduced to just a few hundred dollars per kilogram.

According to de la Torre, the initial investment required for a space elevator may be significant, similar to the expenses incurred in developing and launching the James Webb Space Telescope. However, the costs could be recovered after successfully launching a small amount of payload.

De la Torre believes that with the continuous advancements in materials science, space technology, and engineering, the idea of space elevators should not be dismissed in the near future.

However, until these breakthroughs in materials science occur, the concept of space elevators may remain confined to the realm of science fiction enthusiasts.

De la Torre emphasizes that space elevators have the potential to revolutionize humanity’s ability to explore space. They could provide a safe and cost-effective means of transporting heavy payloads required for various purposes such as space stations, asteroid mining, or the development of extraterrestrial habitats.

This article is republished from PhysORG under a Creative Commons license. Read the original article.