SpaceX – With the number of tools at our disposal, it’s no surprise that the spacecraft industry has improved.
With more satellites in the sky, it’s nearly impossible to gauge which belongs to which company.
SpaceX (Space Exploration Technologies Corp) is among those with a number of satellites above the globe, taking up over half of the active space stations.
Although it is an incredible feat, it is also creating a problem as the number of satellites in low Earth orbit is increasing at a rate that regulations can’t keep up.
On February 27, SpaceX launched 21 new satellites to link up with the broadband Starlink fleet.
As a result, there are now 3,660 active Starlink satellites.
According to astronomer Jonathan McDowell’s analysis, it takes up over 50% of nearly 7,300 active satellites in orbit.
“These big low-orbit internet constellations have come from nowhere in 2019, to dominating the space environment in 2023,” said McDowell.
“It really is a massive shift and a massive industrialization of low orbit.”
Streaks in the sky
Since 2019, SpaceX has been launching Starlink satellites into orbit to bring broadband internet to remote areas of the globe.
For the same span, astronomers have warned that the SpaceX satellites could affect their work, messing up their view of the cosmos with streaks on telescope images whenever they glide by.
The Hubble Space Telescope, launched in 1990 that orbits more than 310 miles from Earth’s surface, is prone to capturing the satellite streaks.
Astronomer Sandor Kruk of the Max-Planck Institute for Extraterrestrial Physics in Garching, Germany, and her colleagues released a report on March 3 for Nature Astronomy.
They said the number of Hubble images affected by low-orbit satellite lights increased by 50%.
The number of images blocked by satellites is still small.
However, it rose from nearly 3% between 2002 and 2005 to over 4% between 2018 and 2021 for Hubble’s cameras.
A factor to consider is how there are now thousands more Starlink satellites than in 2021.
“The fraction of [Hubble] images crossed by satellites is currently small with a negligible impact on science,” said Kruk and her colleagues.
“However, the number of satellites and space debris will only increase in the future.”
The team estimates that by the 2030s, the probability of a satellite getting into Hubble’s field of view any time it captures an image will be between 20% and 50%.
For the study, they looked at more than 100,000 individual Hubble images by over 10,000 citizen scientists involved in the Hubble Asteroid Hunter project.
A deep learning algorithm was trained to spot images with satellite streaks while ignoring similar features caused by natural phenomena like:
- Cosmic rays
- Gravitational lensing
While the data for the analysis stopped in 2021, more satellites are working in orbit, which means the problem is much worse.
Kruk and her colleagues came up with a grim conclusion, writing:
“With the growing number of artificial satellites currently planned, the fraction of Hubble Space Telescope images crossed by satellites will increase in the next decade and will need further close study and monitoring.”
Read also: SpaceX’s Starlink Redefines Connectivity, Brings High-Speed Broadband Internet Even to Remote Areas
According to astronomer Samantha Lawler of the University of Regina in Canada, the jump in Starlink satellites poses a problem: space traffic.
Starlink satellites all orbit the same distance from Earth.
“Starlink is the densest patch of space that has ever existed,” said Lawler.
The satellites navigate out of each other’s way, avoiding collision.
Additionally, 310 miles is a popular altitude, where it is home to Hubble, the International Space Station, and the Chinese space station.
“If there is some kind of collision [between Starlinks], some kind of mishap, it could immediately affect human lives,” Lawler added.
SpaceX launches Starlink satellites at least once a week.
On March 3, it launched 51 satellites.
Furthermore, SpaceX is joined by other companies also launching internet satellite constellations.
Experts predict that there could be 100,000 satellites taking up low Earth orbit by the 2030s.
For now, no international regulations curb the number of satellites a private company can launch or limit the orbits they can occupy.
“The speed of commercial development is faster than the speed of regulation change,” said McDowell.
“There needs to be an overhaul of space traffic management and space regulation generally to cope with these massive commercial projects.”
A need for regulation
Astronomers have been organizing to prevent the situation from worsening.
In a recent development, an international collaboration petitioned the United Nations for help, requesting an expert group to be assembled to address the situation.
Meanwhile, astronomers can apply data and filtering techniques to identify (and potentially salvage) ruined images.
NASA stated that most affected images are still usable, but the added time and cost for astronomical research aren’t ideal.
Additionally, astronomers are asking satellite operators to work with them, including making the satellites less reflective.
SpaceX responded to the request by experimenting with mitigation techniques for Starlink, like dark paint to absorb sunlight.
However, the mitigation was less effective than they wanted.
They have also tried different approaches, like adding a visor to block reflective sunlight and adjusting orientations to minimize surface area, which the company claims are highly effective.
Furthermore, SpaceX is experimenting with “dielectric mirror film” to direct light away from Earth.
Image source: EarthSky