Is Starlink Dangerous To Humans? These Are 6 Possible Threats

There’s no denying the impact that Starlink had on people in rural areas and beyond. In 2022 alone, it quadrupled its subscriber base from 250,000 to now over 1 million.  

However, as its reach increase, experts and casual users alike become increasingly worried about the dangers that a constellation like Starlink poses.

In summary, those potential threats are space debris, in-space collisions, national security, hacking of the dishes and software, asteroid detection, and environmental threats.

Without further ado, let’s take a closer look at each of them.

1. Potential Danger: Space Debris

Starlink eventually plans to deploy around 42,000 of its own satellites into earth’s low orbit (LEO), with the confirmation by the Federal Communications Commission (FCC) still pending.

In early December 2022, the agency granted approval for SpaceX to launch 7,500 of Starlink’s Gen2 into LEO.

The FCC imposed a limit on the number of Gen2 satellites SpaceX can deploy “to address concerns about orbital debris and space safety.”

Let’s address the first concern the FCC has, which is that of space junk. To date, SpaceX has launched over 3,600 Starlink satellites into space, of which around 3,300 remain in orbit.

Satellites become unusable for a variety of different reasons. Examples include the malfunctioning of hardware, solar storms, or in-space collisions.

Related: everything you need to know about Starlink

And even the ones that work perfectly fine will ‘only’ remain in space for around 5 years after which they deorbit.

This means that 23 satellites would come back down to earth every day if Starlink ever reaches its proposed constellation of 42,000.

As a result, regulators and spectators alike have issued concerns about space trash damaging humans down on earth. One of the greatest fears is that satellite parts may hit someone.

First-gen Starlink satellites weigh 573 lbs. (260 kilograms). By contrast, Gen2 modules are considerably heavier at 2,755 lbs (1,249 kilograms), thus requiring more powerful rockets like SpaceX Starship to be transported into orbit.

With such heavy loads, it wouldn’t be unfounded to assume that satellite parts may pose dangers to humans. However, there are several mitigating factors that make this an unlikely scenario.

The biggest one is that SpaceX designed the satellites so that they quickly disintegrate when they re-enter earth’s atmosphere. The forces of atmospheric drag and heat during this descent can be so strong that even objects like satellites may disintegrate completely.

So, the concern that a whole satellite may hit a human is completely unwarranted. But what about individual parts? Even those concerns should be neglectable given they are very likely to completely burn out.

Additionally, the great majority of satellites land in locations that aren’t inhabited by humans, to begin with. Astronomer Jonathan McDowell, who runs a highly-recommended site tracking Starlink launches, previously plotted the re-entry locations of 102 satellites.

Of the 260 Starlink satellites that have reentered so far, we have reentry locations for 102. This plot illustrates that the locations are random, consistent with the fact that the final week of their orbital decay and reentry is uncontrolled pic.twitter.com/brnU18xCfI

— Jonathan McDowell (@planet4589) July 25, 2022

As you can see from the graph above, the majority of satellites come down back to earth either hitting the ocean or land that isn’t necessarily inhabited by humans.

The notion is supported by calculations that SpaceX made using NASA’s Debris Assessment Software. The software tool determined that there was a 1 in 18,200 chance that one of its satellites could hurt or kill a human.

In summary, the danger of satellites and parts hurting humans on earth is neglectably low. But what about the ones that roam space?

2. Potential Danger: Collisions

Think about the following scenario: a satellite roaming the earth is being destroyed, which leads to all kinds of havoc being wreaked as individual parts start crashing into each other.

As those parts roam around uncontrollably, they start hitting space shuttles, telescopes, and other objects – some of which are inhabited by astronauts. Eventually, the International Space Station (ISS) is hit by all kinds of space junk and killing everyone on board.

If this scenario sounds all too familiar, then you’re as much of a movie enthusiast as me. Those scenes were pulled from the award-winning movie Gravity, which was released back in 2013. But every great story also has a kernel of truth to it, with Gravity being no exception.

The movie is a fictional translation of the so-called Kessler Syndrome, which was first published by NASA scientist Donald J. Kessler in 1978.

Kessler and co-author Burton Cour-Palais plotted a scenario in which the chance of satellite collisions increases with every new object lofted into space. The biggest issue is that even smaller objects pose serious threats to larger spacecrafts as highlighted by the National Academy of Sciences:

“A 1 kg object impacting at 10 km/s, for example, is probably capable of catastrophically breaking up a 1,000 kg spacecraft if it strikes a high-density element in the spacecraft. In such a breakup, numerous fragments larger than 1 kg would be created.”

The issue may only be amplified by the mega-constellations that SpaceX, Amazon via Kuiper Systems, OneWeb, and others aim to assemble.

Generally speaking, the higher up a satellite is located, the longer it remains in space. NASA provides us with the following rule of thumb:

“The higher the altitude, the longer the orbital debris will typically remain in Earth orbit. Debris left in orbits below 370 miles (600 km) normally fall back to Earth within several years. At altitudes of 500 miles (800 km), the time for orbital decay is often measured in decades. Above 620 miles (1,000 km), orbital debris normally will continue circling Earth for a century or more.”

All of Starlink’s satellites fall within the first category while competitors like OneWeb operate at 1,200 km (750 miles) altitude.

There are some data points that underline the threat of collisions. Back in February 2022, NASA issued a letter, stating that collision risk with crewed missions was a serious concern for the agency. Additionally, it also had to delay launches due to passing satellites.

A year prior, the Chinese government addressed the United Nations and stated that the country’s space station had to perform emergency maneuvers to avoid crashing into Starlink satellites.

SpaceX issued a response to address all of those concerns and highlighted the measures it undertakes to avoid any collision in space:

• Starlink representatives can be reached 24/7/365 to coordinate with other agencies and operators
• Each satellite boasts a built-in anti-collision system that changes the object’s direction once the probability of a crash is greater than 1/100,000 (the industry standard for a maneuver is 1/10,000 probability)
• All Starlink satellites, as mentioned above, operate in a “self-cleaning” distance to earth, which means they naturally deorbit within around 5 years and burn up when entering earth’s atmosphere
• SpaceX shares data with various agencies such as the FCC, the U.S. Space Force, and even publicly accessible websites like Space-Track.org

Additionally, SpaceX has since entered into agreements with some of its competitors to share real-time data about the location of each satellite. In June 2022, for example, SpaceX and OneWeb announced that they would ensure that their respective constellations communicate with each other.

Three months later, the two companies, plus Iridium, released a document that detailed best practices for safety in space. Those best practices, as they said, would hopefully set standards for all phases, meaning the design, launch, and deorbiting.

With that being said, the potential of collision is undeniably a major concern for everyone involved. It remains to be seen how Starlink and other operators address them going forward.

3. Potential Danger: National Security

Apart from the physical encounter with satellites and their parts, various experts have also highlighted the potential threat Starlink could pose to their national security.

When the war in Ukraine broke out, SpaceX quickly shipped thousands of dishes to the country, thus enabling Ukrainian troops and citizens to communicate with each other and stay online (since cell towers were destroyed by the Russians).

“There are some features of Starlink that make it different from previous generations of satellite communications technology used in conflicts,” said John Scott-Railton, a senior researcher at Citizen Lab at the University of Toronto’s Munk School in an interview with Insider.

For example, he pointed out that the dishes are “visually distinctive,” meaning they could be seen from afar. Russian troops could then target those dishes and the people surrounding them.

The second and more worrying aspect is that the radio signals which Starlink emits are trackable. As a result, Russia’s intelligence could potentially identify the signal transmitter and consequently attack said those locations.

Ukrainians aren’t the only ones that would be concerned about Starlink, though. In May 2022, China’s national security threatened to destroy Starlink satellites due to their “huge potential for military applications.”

Fittingly, Starlink unveiled a new product called Starshield in December 2022, which is designed for (U.S.) government use. The system has three key focus areas, namely imagery, communications, and hosted payloads.

Consequently, Starlink advertises its Starshield offering as a comprehensive solution for national security, which would include building and launching satellites, operating the network in space, and providing ground antennas.

Musk and SpaceX likely launched Starshield to get on the good side of the government. After all, it needs FCC approval to be able to launch satellites into space. By offering government-critical services, it becomes substantially easier to receive those permits and thus extend its lead over the competition.

But governments around the world aren’t the only ones concerned about Starlink’s impact. Individual consumers are faced with the threat of hacking as well.

4. Potential Danger: Hacking

Nations aren’t the only ones that should be worried about Starlink devices being compromised. Potential backdoors would allow hackers to access the data that is being transmitted via a Starlink device.

Security researcher Lennert Wouters, back in August 2022, successfully hacked a Starlink dish using equipment that only cost $25.

The tool, which is a custom circuit board known as a modchip, would simply be mounted to the dish. He then launched a so-called fault injection attack, which allowed Wouters to bypass any present security measures.

Luckily for Starlink, Wouter’s intentions were purely academic. He even made the source code and list of equipment used available via GitHub.

He first notified Starlink representatives who then went on to fix the vulnerability. In exchange, Wouters received financial compensation through Starlink’s bug bounty program.

Added security is particularly important given that Starlink will eventually be used on vessels, airplanes, and so forth.

5. Potential Danger: Asteroid Detection

Remember dinosaurs? Those guys certainly would’ve loved to know that a single asteroid could lead to their extinction.

Starlink and the slew of other satellites set to be launched by its competitors are already visible in the night sky.

In fact, they are so evident that astronomers now repeatedly see them marked on their telescope images.

More precisely, they create streaks that stretch alongside an entire image. The Zwicky Transient Facility, which is run by the California Institute of Technology (Caltech), released an example of such a streak back in January 2022.

In the associated paper, lead author Dr. Przemek Mróz stated that “in 2019, 0.5 percent of twilight images were affected, and now almost 20 percent are affected.”

One of the biggest concerns about tainted images is that they may negatively affect the detection of so-called killer asteroids.

Jonathan McDowell pointed this out all the way back in 2020 when he released a paper on the potential harms that Starlink’s constellation could pose.

“For example, searches for near-Earth asteroids include observations taken in twilight, a time when the satellites are illuminated year-round,” he stated in the paper.

Those concerns were reiterated by NASA in its letter, with the agency estimating that a Starlink satellite could appear in “every single asteroid survey image taken for planetary defense against hazardous asteroid impacts, decreasing asteroid survey effectiveness by rendering portions of images unusable.”

In fairness, the satellites currently affect less than 0.5 percent of all pixels within an image. Software may also help to remove stretches.

SpaceX itself has also addressed some of those concerns by adding visors to its satellites. This change, implemented in 2020, has successfully reduced the satellites’ brightness by 4.6x.

Starlink later released a letter to highlight the practices it undertakes to further mitigate brightness. Those include:

• the Gen2 satellites will utilize three advanced brightness mitigation techniques, namely a dielectric mirror film (10x improvement vs. Gen1)
• pointing solar arrays away from the sun (to scatter sunlight hitting the front side of the solar arrays)
• using a “Low Reflectivity Black” paint on as many parts as possible

Notwithstanding, the likeliness of a killer asteroid not being detected at all and consequently being on course to earth is incredibly low – at least if you don’t star in a Netflix movie.

6. Potential Danger: Environmental Effects

Researchers Aaron C. Boley and Michael Byers, back in May 2021, co-authored a paper titled ‘Satellite mega-constellations create risks in Low Earth Orbit, the atmosphere and on Earth.’

In the paper, they argue that the chemicals of defunct satellites that burn up when re-entering earth’s atmosphere could damage the planet’s protective ozone layer.

As I’ve outlined above, if SpaceX were to implement its constellation of 42,000 satellites, then 23 of them would deorbit every day.

In particular, burned aluminum, which is called aluminum oxide (alumina), is known to be particularly damaging to the earth’s protective layer.

The rockets themselves also contribute to the problem. “We know that alumina does deplete ozone just from rocket launches themselves because a lot of solid-fuel rockets use, or have, alumina as a byproduct,” Boley said in the paper. “That creates these little temporary holes in the stratospheric ozone layer. That’s one of the biggest concerns about compositional changes to the atmosphere that spaceflight can cause.”

U.S.-based competitor Viasat has tried to use those concerns to its advantage, too. It addressed the FCC in a letter and asked the regulator to outright ban SpaceX from launching any more satellites.

Right now, there is no conclusive evidence that supports the above-outlined assumptions. However, as the authors said in the paper, “humans are exceptionally good at underestimating our ability to change the environment.”