LibGuides: Space Race (21st Century): Concerns

Space Concerns

The New Space Race - Starlink Satellites - Sky & Telescope
Satellites represented the initial phase of SpaceX's Starlink megaconstellation, a giant network of satellites buzzing around Earth. OneWeb, for example, cannot dynamically share radio frequencies because its satellites' beams are both fixed and, due to its satellites' higher orbits, necessarily much larger than Starlink's steerable beams. SeeSat-L contributors Jay Respler, Brad Young, Bram Dorreman, and Ron Lee observed Starlink satellites in July and August 2019, when the majority of the first batch of Starlink satellites had reached 550 km. Right: Future satellite visibility is based on FCC filings, with 11,927 Starlinks, 1,980 OneWeb satellites, and 3,236 Kuiper satellites.
Space pollution - Scientific American
The article discusses the issues related space pollution and new private launch industry can learn a lot from aviation about sustainability. It mentions space, rockets and satellites are most often corporate investments or public-private partnerships and focused on jet engine emissions and honing turbine combustion to near theoretical maximum efficiency. It also mentions environmental impacts of launch vehicles are typically disregarded by comparing jet and rocket fuel consumption.
Simulated space radiation sensitizes bone but not muscle to the catabolic effects of mechanical unloading - PloS One
Deep space travel exposes astronauts to extended periods of space radiation and mechanical unloading, both of which may induce significant muscle and bone loss. Astronauts are exposed to space radiation from solar particle events (SPE) and background radiation referred to as galactic cosmic radiation (GCR). To explore interactions between skeletal muscle and bone under these conditions, we hypothesized that decreased mechanical load, as in the microgravity of space, would lead to increased susceptibility to space radiation-induced bone and muscle loss.

How Blue Origin, SpaceX, Virgin Galactic space race could impact the atmosphere

The space industry is taking off after decades of stagnation.

Driven largely by the rapidly developing space programs of Elon Musk’s SpaceX and China, the world saw 114 orbital launches in 2018 — the first triple-digit showing since 1990. This year, orbital launches are on track to exceed 130 for the first time since the 1970s. And that count doesn’t include recent suborbital tourism excursions from Jeff Bezos’ Blue Origin and Richard Branson’s Virgin Galactic.

Between NASA planning its lunar return, SpaceX constructing a massive “megaconstellation” of internet satellites, China crewing a space station and suborbital companies sending crews of tourists to the edge of space, launches may soon become a daily occurrence.

So far, the fledgling space industry does not seriously threaten the environment and likely has room to grow. Whether that will change as the new space race accelerates, however, is anyone’s guess.

Most rockets do emit more planet-warming carbon than many planes. Experiencing a few minutes of weightlessness on Virgin Galactic’s spaceplane will rack up a carbon footprint comparable with flying business class across the Atlantic, and one orbital launch of SpaceX’s upcoming fully reusable Starship will emit as much carbon dioxide as flying a plane continuously for about three years, according to a back-of-the-envelope calculation by Whittaker.

Quoted from:
Wood, C. (2021, August 27). How Blue Origin, SpaceX, Virgin Galactic space race could impact the atmosphere. CNBC.
https://www.cnbc.com/2021/08/27/how-blue-origin-spacex-virgin-galactic-space-race-could-impact-the-atmosphere.html