When LEO Fails: The case for stratospheric infrastructure

Kessler Syndrome, Space War, Solar Storms, Regulatory Failure - HAPS to the rescue

Low Earth Orbit is the most consequential shared commons humanity has ever built on, yet we are treating it like a landfill. GPS, broadband, weather forecasting, military ISR, financial timing, precision agriculture all share one thing: they all depend on a thin band of space between 300 and 2,000 kilometers above Earth. If that band degrades, they all go down together. The question is not whether LEO will face a crisis but what form it will take - and whether we have a fallback. This post explores the problem space and potential mitigators.

https://www.cosmos.so/e/54523896

The Fragility of Orbit

LEO faces several risks, some more detrimental and more probable than others. Let’s explore them one by one.

Kessler Syndrome

In 1978, NASA scientist Donald Kessler described a feedback loop: collisions in orbit create debris, which creates more collisions, which creates more debris, until an orbital band becomes unusable. For decades this was treated as a distant concern. It is now an operational reality.

The numbers are past the threshold. A March 2025 analysis by Lewis and Kessler using the latest population data found that the current number of intact objects exceeds the runaway threshold at nearly all altitudes between 520 km and 1,000 km. Planned mega-constellation deployments will push even more altitude bands beyond stability limits.

The operational evidence. SpaceX’s Starlink constellation - 9,300+ satellites as of late 2025 - performed 300,000 collision avoidance maneuvers in 2025 alone. That is roughly 820 maneuvers per day. And each new satellite added to orbit increases collision probability with every existing satellite.

The CRASH Clock tells the story. Researchers developed a metric called the Conjunction Risk Assessment for Space Highways - which tells us how quickly satellites would start colliding if they lost the ability to avoid each other. In 2018, it stood at 164 days. By January 2026, it had collapsed to 3.8 days. The safety margin eroded by 97% in eight years. IEEE Spectrum’s analysis notes an important nuance: the CRASH Clock measures time to the first collision, not a full Kessler cascade. But a first collision is exactly how a cascade starts - and 3.8 days without active avoidance is the margin that stands between operational orbit and the beginning of a chain reaction.

ESA’s 2025 Space Environment Report tracks over 40,000 objects, with models estimating 1.2 million objects larger than 1 cm and 130 million larger than 1 mm. The 2009 collision between Iridium 33 and Cosmos 2251- a single event - created over 1,800 trackable debris fragments, many of which will remain in orbit for decades. The collision doubled the risk in the 700-800 km altitude band.

Now imagine this with 15,000-18,000 satellites in LEO by end of 2026, and China filing for a 200,000-satellite constellation.

Space War

Kessler Syndrome is an accident. Space war is a choice - and the arsenals are ready.

**Kinetic anti-satellite weapons (ASAT): Russia’s November 2021 test destroyed its own Cosmos 1408 satellite, generating 1,500+ trackable debris fragments at 480 km altitude - directly threatening the ISS and Starlink’s orbital band. China demonstrated kinetic ASAT capability in 2007 by destroying a weather satellite, creating debris still tracked today. The US, India, and likely others have operational capability.

Directed energy weapons: China has likely fielded ground-based lasers capable of dazzling or damaging low-orbit satellite sensors. Russia has deployed the Peresvet system with mobile ICBM units. The U.S. Space Force is deploying electronic satellite jammers and accelerating counterspace weapons development. Every major debris removal laser has inherent dual-use capability - the ablation mechanism works identically on debris and functional satellites.

Cyber warfare: The 2022 Viasat/KA-SAT attack at the start of Russia’s invasion of Ukraine disabled satellite broadband across Europe in hours - a single cyberattack that affected tens of thousands of terminals. The CSIS 2025 Space Threat Assessment reports that cyberattacks, jamming, and spoofing have “become commonplace and rarely trigger an escalatory or retaliatory response.” GPS jamming is now routine across the Baltic, Middle East, and South Asia.

Nuclear EMP: Russia is reportedly developing an orbital nuclear anti-satellite capability. A nuclear detonation in LEO would not just destroy nearby satellites - it would create an electromagnetic pulse and a persistent radiation belt (similar to the 1962 Starfish Prime test) that could degrade electronics on every satellite passing through the affected region for months or years.

The Secure World Foundation’s 2025 Global Counterspace Capabilities report grew from 148 pages in 2018 to 316 pages in 2025, tracking 12 nations with active counterspace programs. The domain is militarizing faster than governance can respond.

The cascading scenario: A kinetic ASAT strike during a Taiwan Strait conflict could deliberately trigger a Kessler cascade in specific orbital bands. Even a “limited” exchange - targeting 10-20 reconnaissance satellites - would generate thousands of debris fragments, each capable of destroying other satellites. The debris does not distinguish between military and civilian infrastructure. GPS, Starlink, weather satellites, and the ISS all share the same orbital neighborhood.

Solar Weather

The Sun is indifferent to human infrastructure planning.

In February 2022, a moderate geomagnetic storm during the rising phase of Solar Cycle 25 increased atmospheric drag in LEO, causing 38-40 newly launched Starlink satellites to lose altitude and burn up before reaching their operational orbit.

We are currently near the maximum of Solar Cycle 25. Research published in Frontiers in Astronomy and Space Sciences (2025) shows that reentry rates for LEO satellites have increased significantly during this solar maximum, with atmospheric drag becoming harder to predict as solar activity fluctuates.

The Carrington scenario: A Carrington-class event (the 1859 solar superstorm, the strongest recorded) directed at Earth would be categorically different from a moderate storm. Simulations suggest it could disable or degrade a significant fraction of LEO satellites through radiation damage to electronics, dramatically increased atmospheric drag, and disruption of ground control links. New simulations warn that a Carrington-level event could “wipe out all our satellites.”

The probability is not negligible. Solar physicists estimate a 1-12% probability per decade of a Carrington-class event. Over a 50-year infrastructure planning horizon, the cumulative probability becomes significant.

Economic and Regulatory Failure

LEO’s commons problem is economics.

The bankruptcy scenario: Starlink reached profitability in 2024 - barely, with $72.7 million net profit on $2.7 billion revenue. Project Kuiper has invested $10B+ and must launch 1,600 satellites by July 2026 just to retain FCC license rights. China’s constellations are state-backed. OneWeb went bankrupt once already. If a mega-constellation operator fails, thousands of uncontrolled satellites remain in orbit with no entity responsible for their disposal. At a 1-2% annual failure rate, even a healthy Starlink generates 20-40 derelict satellites per year that cannot self-deorbit.

No enforceable global space traffic management exists. ITU spectrum allocation operates first-come-first-served. China’s 200,000-satellite filing is a spectrum land-grab, not a real deployment plan. The FCC regulates US operators but has no jurisdiction over Chinese or Russian constellations. Active debris removal technology exists (ClearSpace, Astroscale) but remains entirely government-funded. There is no commercial market because there is no mandatory liability framework. A proposed EU Space Act (June 2025) covers only EU-licensed operators.

Insurance barely covers the risk. Only about 6% of satellites carry in-orbit insurance. The space insurance market cannot price catastrophic correlated events (Kessler cascade, solar superstorm) because they would simultaneously affect all insured assets. This is not insurable risk. It is too systemic. A PNAS analysis found that a harmonized orbital-use fee of ~$235,000 per satellite-year would correct incentives and increase long-run industry value from ~$600B to ~$3T. No such mechanism exists.

The Correlation Problem

This is the factor that transforms LEO vulnerability from a sectoral concern into a civilizational one. All LEO-dependent services share the same physical environment. A debris cascade, solar storm, or ASAT campaign does not selectively degrade broadband while leaving GPS intact. It does not spare weather satellites while destroying ISR platforms. The failure mode is correlated across every service category.

A modern economy losing GPS simultaneously with satellite broadband and weather forecasting faces compounding failures that no sector-specific contingency plan addresses. Financial markets lose timing synchronization. Aviation loses precision approach capability. Precision agriculture loses guidance. Military forces lose ISR and secure communications simultaneously. Maritime shipping loses AIS and navigation.

LEO is a single point of failure for civilization-scale infrastructure. No equivalent single-point-of-failure exists in terrestrial infrastructure - no one earthquake can simultaneously disable the internet, GPS, weather forecasting, and military communications globally.

The Stratospheric Alternative

At 20 kilometers altitude, above weather and conventional air traffic but far below the orbital debris field, there exists a layer of the atmosphere that is largely empty, physically benign, and operationally proven.

The stratosphere is a hedge against LEO’s correlated failure modes - and for several applications, it is the superior solution regardless.

The Physics Case

The comparison between a satellite at 500 km and a stratospheric platform at 20 km comes down to distance - and the physics of distance are unforgiving.

Signal strength: Free Space Path Loss (FSPL) at 10 GHz from 20 km altitude is 138 dB; from 500 km it is 166 dB. The 28 dB difference sounds small until you remember that decibels are logarithmic- every 10 dB represents a 10x change in power. So 28 dB = 10^(28/10) = ~630x more signal power reaching a ground receiver from a HAPS than from a LEO satellite. A stratospheric platform talking to a standard 4G handset has physics working in its favour by nearly three orders of magnitude.

Latency: Round-trip latency from 20 km is approximately 0.13 milliseconds. From 500 km LEO orbit, it is 3.33 milliseconds. From GEO, it is 600+ milliseconds.

Imaging resolution: The Rayleigh criterion for diffraction-limited optics means that achieving 10 cm ground resolution from 500 km requires a 3.05 meter mirror. From 20 km, the same resolution needs a 12.2 cm lens. 25x times smaller. This is why satellites top out around 30 cm commercial resolution while HAPS can achieve sub-10 cm with modest optics.

Direct-to-hand-held-device connectivity: The April 2025 HAPS Alliance whitepaper establishes that HAPS are compatible with existing 4G/5G handsets without modification. Satellite direct-to-device (Starlink, T-Mobile partnership) requires specialized protocols and delivers a fraction of the throughput. In early 2025, Aalto’s Zephyr demonstrated the first wireless connection from a fixed-wing HAPS at 60,000 feet to a standard 4G mobile device on the ground.

dB is a logarithmic scale. 166 vs 138 = 28 dB difference = 10^(2.8) = ~630x power difference. The numbers look close; the physics are not.*

Technology Maturity

In April 2025, Airbus subsidiary AALTO’s Zephyr completed 67 days, 6 hours, and 52 minutes of continuous stratospheric flight - a world record. Solar-powered, battery-sustained through the night, operating at 60,000+ feet. It is an operational endurance demonstration exceeding most military deployment cycles.

The HAPS ecosystem in 2025-2026:

Radical (Seattle, US): A fixed wing form factor; solar powered; flew their full systems maiden flight in autumn 20254; (an Inflection portfolio company)

Aalto/Zephyr: 67-day record. Commercial entry-into-service in Japan planned for 2026, backed by $100M consortium (NTT DOCOMO, Space Compass, Mizuho Bank, DBJ)

Kea Aerospace (New Zealand): Historic first stratospheric flight, February 8, 2025. Atmos Mk1b reached 56,284 feet, flew 8 hours 20 minutes

Sceye (US): NASA/USGS partnership for methane monitoring. SoftBank investment. Pre-commercial HAPS services in Japan 2026

BAE Systems PHASA-35: Presented at DSEI 2025 as a defense product for persistent ISR and communications. Months-long endurance without landing

India DRDO AS-HAPS: First flight trials May 2025 at 17 km altitude. Defence Acquisition Council approved

Russia Barrage-1:Tested February 2026: - a stratospheric aerostat developed explicitly as a Starlink alternative after SpaceX restricted access to Russian military user. The proliferation is telling. When Russia builds a battlefield stratospheric relay within weeks of losing Starlink access, the dependency - and the remediation speed - are clear.

The Resilience Case

When LEO degrades - through debris cascade, ASAT strike, or solar storm - the stratosphere remains intact. A HAPS at 20km sits below the orbital debris field, is shielded from radiation by the atmosphere, presents no viable ASAT target, and can be replaced in days rather than years. It is an independent infrastructure layer whose failure modes are uncorrelated with orbit.

The applications that matter most in a LEO-denial scenario are precisely where HAPS excels:

For connectivity, a single platform covers a 50km+ radius with direct-to-device service to standard handsets, deployable from a portable ground station in hours - Japan’s SoftBank/Sceye program is explicitly designed for earthquake disaster recovery, and Taiwan demonstrated 14+ days of balloon-based emergency comms in 2025.

For navigation, a HAPS pseudolite at 20km delivers a signal roughly one million times stronger than GPS at 20,200km, making it much harder to jam while providing sub-meter accuracy over sovereign territory that can be repositioned in hours.

For ISR and earth observation, sub-10cm resolution with indefinite dwell time and real-time video replaces the satellite model of daily revisits at 30cm with minutes of dwell per pass - the difference between a photograph and continuous surveillance. Defense analysts are converging on a three-tier aerial architecture - aircraft, stratospheric HAPS, and space - treating the stratosphere as an existential building block.

Building the Mitigation Stack

The five failure modes described above are not inevitable. They are engineering problems. Three companies in Inflection’s portfolio are building specific capabilities to extend LEO’s operational life and mitigate its risks.

If the CRASH Clock reads 3.8 days, the first question is: can we track what we need to avoid? Foundational builds the precision tracking layer for space situational awareness using Space Laser Ranging (SLR). Where radar tracking provides meter-level accuracy, SLR provides sub-centimeter-level precision - 1,000x more accurate. The difference matters when you are trying to predict whether two objects at 7.5 km/s will miss each other by 10 meters or collide.

Tracking threats is necessary but not sufficient. Something must physically intervene. Lodestar is building autonomous satellite defense capabilities in contested space environments. Their system provides onboard decision-making - using game theory to predict adversary intent, detect threats, and execute orbital responses without ground control.

Radical is building autonomous solar-powered aircraft that fly perpetually in the stratosphere at 20km altitude. An aircraft can deliver what a constellation of thousands of satellites struggles to match. Two verticals: (1) connectivity - beaming 5G-speed internet directly to handheld devices over a 50km+ radius, targeting 3 billion underserved people, and (2) persistent imagery - real-time sub-10cm resolution earth observation including live video, physically impossible from orbit due to lens size and revisit constraints.

If you’re building related solution to mitigate infrastructure fall outs due to LEO failure, please get in touch.