Research
Unless the situation is suitably managed at the market access stage, the way LEO is being populated today poses a threat to innovation, growth opportunities, efficient spectrum use, national interests, space safety, and the environment.
Ensuring Innovation and Growth Opportunities in the New Space Age (2024)
Recurring misrepresentations are being made that LEO orbits between 500 km and 600 km in altitude are intrinsically “self-cleaning”, and that collisions of satellites in those orbits are inconsequential. That is wrong. LEO satellite collisions at these altitudes have consequences that persist for decades and threaten all LEO orbits.
Developing congestion in LEO significantly increases the risk of collisions, and longstanding impacts on access to space by everyone. We do not have to accept these consequences. Innovative new systems can deliver better service, ensure space sustainability, and allow all nations to compete in the New Space economy.
Large constellation operators can reduce the risk of a Kessler Syndrome by deploying smaller satellites, or if deploying larger satellites doing so at lower orbits.
Smaller, less massive, satellites in lower orbits may be the key to sustainable LEO constellations.
Deorbiting satellites will be tracked and operational satellites can maneuver to avoid close conjunctions. However, this depends on ongoing communication and cooperation between operators, which at present is ad hoc and voluntary.
The public satellite catalog does not contain all debris objects, as it includes few objects smaller than 10 cm. Yet it is commonly understood that objects that are 1 cm or larger in size can be lethal to a spacecraft if the two collide.
The operation of large numbers of LEO satellites in mega-constellations significantly raises the risk of collisions in space.
Mehlman, Janka, and Sturza. “Averting Environmental Risks in the New Space Age.” Day One Project.
With this level of orbital density, according to multiple modelling efforts, it is not a question of if a defunct satellite will collide with debris, but when.
One of the major challenges with space is that poor debris mitigation practices can quickly affect all space operators.
If current satellite internet proposals become reality, about 50,000 active satellites will orbit overhead within ten years. Even if the most ambitious plans do not come to pass, the satellites will be manufactured and launched on an unprecedented scale.
When calculations are performed looking for potential conjunctions (intersecting error ellipsoids) so many “potential” collisions are identified that they are routinely ignored. It is vital that this situation be remedied before a major accident occurs.
Association of Space Explorers. “Space Traffic Management and Orbital Debris.”
A recent ASAT test has focused attention and discussion on the consequences of space debris at LEO and the fragility of near-earth orbits. This paper compares the aftermath of an accidental satellite collision to that of a successful ASAT test. The results are indistinguishable.
Satellite Collisions Have the Same Consequences as ASAT Tests
Realized risk metrics are inadequate for effectively constraining the probability of collisions involving a LEO constellation over its orbital lifetime to levels that align with the safe and sustainable use of space. A comprehensive regulatory framework must evaluate the total risk profile presented by a LEO constellation over its orbital lifetime to facilitate the long-term safety, sustainability, and use of space.
Realized Collision Risk (2024)
It is commonly believed that “resilience” of a proliferated LEO constellation increases as the number of satellites increases. We show that increasing the number of satellites in a large LEO constellation may significantly increase the number of consequential collision events due to a fragmentation event. As a result, large LEO constellations may impose a significant cost to all constellations.
Resilience of LEO Constellations to Accidental and Intentional Fragmentation Events (2024)
Policy
...NASA has concerns with the potential for a significant increase in the frequency of conjunction events and possible impacts to NASA's science and human spaceflight missions.
Further, the rise in orbital debris in space compromises valuable assets and threatens to make space inaccessible.
Letter from U.S. Rep. Mark Levin (D-CA) to Acting FCC Chair Rosenworcel
In the last decade, two major satellite collisions dramatically increased the amount of fragmented debris currently in orbit.
Letter from U.S. Senators Cory Booker (D-NJ) and Dan Sullivan (R-AK) to FCC Chair Ajit Pai
Much has changed in the space environment over the past two decades, but one thing is clear: congestion in space — especially the explosive growth in space debris — has created an increasingly dangerous environment for our astronauts and satellites in orbit.
Op-Ed from Sen. Roger Wicker (R-MS): Protecting our assets from space debris
It is essential that the Commission’s understanding of orbital regimes, and the decisions operators base on that understanding, be shaped by an accurate measure of the risk of collision between objects in Earth orbit.
We believe that addressing orbital debris and the long-term sustainability of space will require a basket of multiple approaches. There is no silver-bullet solution.
“Spacefaring nations must minimize the risks to people and property on Earth of re-entries of space objects and maximize transparency regarding those operations. It is clear that China is failing to meet responsible standards regarding their space debris. It is critical that China and all spacefaring nations and commercial entities act responsibly and transparently in space to ensure the safety, stability, security, and long-term sustainability of outer space activities.”
Statement from NASA Administrator Bill Nelson (5/8/21)
Media
Viasat Exec Chairman Mark Dankberg sat with Jim Bridenstine, Acorn Growth Companies Senior Advisor, Viasat Board Member and former NASA Chief to discuss how we can ensure safe, sustainable access to space.
Over the summer, SpaceX had lost contact with three Starlinks orbiting earth, leaving experts concerned over the potential for such satellite mega-constellations to add to dangerous orbiting space debris.
Now, Ekaterini Kavvada, the directorate general of Defence Industry and Space at the European Commission, has warned that this space junk is 'not a theoretical threat but a reality'.
"But if we don't address the space-junk crisis at a global level, rather than at an operator one, "we risk missing how the environment is degrading," Daniel Oltrogge, the director at the Center for Space Standards and Innovation...
Space is getting crowded, and experts worry that we might one day face a catastrophic cascade of proliferating space debris, which could in turn knock out satellites, disable GPS service, and generally render space travel and global communications impossible for a generation.
The New Republic: Elon Musk Wants to Move Fast and Break Space
“The mega-constellations are producing huge risks of collisions. We need more stringent rules for traffic management in space and international mechanisms to ensure enforcement of the rules.”
Financial Times: ‘Huge risk’ of space junk collisions as satellite launches intensify, experts warn
Viasat, Amazon and other firms objected to SpaceX’s move on a variety of fronts, including potential signal interference, environmental impacts to the atmosphere and collision risk...
"It’s a race to the bottom in terms of getting as much stuff up there as possible to claim orbital real estate,” said Moriba Jah, associate professor at the Department of Aerospace Engineering and Engineering Mechanics at the University of Texas at Austin.
Wall Street Journal: Elon Musk’s Satellite Internet Project Is Too Risky, Rivals Say
Today, we need to mitigate the risk of “space debris”—spent rocket stages, fuel tanks and decommissioned satellites that could damage other satellites, spacecraft and future human habitats.
Wall Street Journal: Space Is Poised for Explosive Growth. Let’s Get It Right.
For space junk, the implications are stark.
New York Times: What if Space Junk and Climate Change Become the Same Problem?
“We face entirely new challenges as hundreds of satellites are launched every month now — more than we used to launch in a year,”...
Financial Times: ‘Huge risk’ of space junk collisions as satellite launches intensify, experts warn
Some researchers are livid because they fear these objects will disrupt astronomy research.
The worst-case scenario, in which satellite collisions create a runaway feedback loop of ever-greater amounts of space debris, is known as the Kessler syndrome...
Removing from orbit existing large objects that could collide with one another would be a great start for governments.
Low-Earth orbit is already quite crowded. As Musk himself has noted, nearly 5,000 satellites currently swarm the planet’s immediate environment, and Starlink alone is poised to triple that number.
Space junk is a huge problem—and it’s only getting bigger, National Geographic
Low-Earth orbit is already quite crowded. As Musk himself has noted, nearly 5,000 satellites currently swarm the planet’s immediate environment, and Starlink alone is poised to triple that number.
Will Elon Musk’s Starlink satellites harm astronomy? Here’s what we know. National Geographic