Every week, it seems, another rocket is sent into space, this time carrying rovers to Mars, tourists, or, most typically, satellites. The idea that “space is growing crowded” has been around for a while, but how full is it exactly? And how crowded will it become? said Professor of physics at the University of Massachusetts, Lowell, and director of the Center for Space Science and Technology. Many satellites launched into orbit have already died or burned up in the atmosphere, yet many have remained. Although satellite tracking organisations don’t always publish the same precise figures, the overall trend is evident – and stunning.
Since 1957, when the Soviet Union launched Sputnik, the first human-made satellite, humanity has steadily increased the number of objects in orbit each year. There was sluggish but steady growth in the second part of the twentieth century, with around 60 to 100 satellites launched annually until the early 2010s.
However, since then, the rate has accelerated substantially.
By 2020, 114 flights will have launched approximately 1,300 satellites into orbit, breaking the 1,000 new satellites per year barrier for the first time. However, no previous year compares to 2021. Around 1,400 additional satellites have already begun orbiting Earth as of September 16, with the number expected to rise as the year progresses. SpaceX has launched 51 more Starlink satellites into orbit.
Small satellites with easy orbital access
This exponential increase can be attributed to two factors. To begin with, launching a satellite into space has never been easier. For example, on Aug. 29, 2021, a SpaceX rocket delivered many satellites to the International Space Station, including one developed by my students. These satellites will be launched into orbit on Oct. 11, 2021, bringing the total number of spacecraft to a new high.
The second reason is that rockets can now transport more satellites than ever before with greater ease — and at a lower cost. This increase isn’t due to more powerful rockets. Satellites, on the other hand, have shrunk as a result of the technological revolution. The great majority of spacecraft launched in 2020, 94 percent, were smallsats, or satellites weighing less than 600 kg.
The bulk of these satellites are used for Earth observation, telecommunication, and internet access. Two commercial firms, Starlink by SpaceX and OneWeb, launched around 1,000 smallsats in 2020 alone with the purpose of extending the internet to underserved areas of the globe. In the coming years, they both intend to launch more than 40,000 satellites into low-Earth orbit to form “mega-constellations.”
Several other startups, including Amazon’s Project Kuiper, are chasing the $1 trillion industry.
A suffocating sky
With the massive increase of satellites, fears of a congested sky are beginning to materialise. Astronomers noticed the first 60 Starlink satellites blocking out the sky a day after SpaceX launched them. While the impact on visible astronomy is obvious, radio astronomers fear that interference from satellite megaconstellations like Starlink would result in a loss of 70 percent sensitivity in some frequencies.
Experts have been examining and debating the potential challenges created by these constellations, as well as possible solutions offered by satellite businesses. These include lowering the number of satellites and their brightness, sharing their location, and providing better image-processing software, among other things.
Trends in the future
The democratisation of space was a goal that had yet to be realised less than ten years ago.
One could argue that the aim is now within reach, with student projects on the Space Station and more than 105 countries having at least one satellite in orbit.
Every disruptive technological breakthrough necessitates rule changes – or the creation of whole new ones. SpaceX has conducted tests to reduce the impact of Starlink constellations, and Amazon has stated that their satellites will be de-orbited within 355 days of mission completion. These and other activities by various parties gives us faith that commerce, research, and human endeavours will be able to discover long-term answers to this looming catastrophe.