Small satellites have reshaped the landscape of space exploration. Over the past decade, they’ve opened the door to a wave of new actors—startups, universities, and emerging space nations—who previously lacked the budget or infrastructure to participate. Compact, relatively inexpensive, and faster to build than traditional spacecraft, smallsats have become the workhorses of the so-called New Space movement. But this revolution has a blind spot: an alarming rate of failure.
According to NASA data, nearly 40% of small satellite missions over the last twenty years have ended in partial or total failure [1]. These aren't just isolated anomalies. In many cases, the satellites never complete their objectives. While some failures stem from launch mishaps or hardware defects, a growing number arise from less obvious causes: software that behaves unpredictably once in orbit, systems that were never fully tested together, or timing and communication protocols that fall apart under operational conditions [2].
What makes these failures particularly painful is their cost—not just in hardware, but in reputation and opportunity. A single smallsat mission typically costs between $50 and $60 million and can weigh 500 kilograms or more [3]. A loss means more than broken equipment. Companies have seen mission failures wipe out investor confidence or trigger stock price drops. Academic institutions lose years of student and faculty work. Government agencies face public scrutiny and delayed timelines.
Despite the scale of these consequences, testing methodologies in the smallsat sector have not kept pace. While large satellite integrators have long employed full-system digital validation techniques—reducing their failure rates to below 10% [4]—many smallsat teams still focus on individual component testing. They simulate how hardware performs under thermal, vacuum, or vibration stress, but often overlook how systems interact. This results in problems that don't show up until the spacecraft is in orbit, where telemetry fails, commands are misread, or subsystems respond to edge cases in unexpected ways.
The problem isn’t a lack of engineering talent—it’s a mismatch between the complexity of current missions and the tools used to prepare them. Many failures could be avoided not by testing more, but by testing differently. When validation environments focus only on hardware durability, they miss the integration problems that account for the majority of in-orbit breakdowns.
This is why new tools for digital system-level validation are gaining traction. Instead of treating the spacecraft as a collection of isolated components, they simulate the satellite as a functioning system. They recreate not just power consumption or temperature swings, but the flow of commands, data, and software interactions that define how a satellite operates in the real world. This kind of simulation allows engineers to catch issues early—while they’re still fixable.
One of the companies contributing to this shift is Asynchronics, a software firm from Poland. Since 2022, it has been developing NeXosim, an open-source simulator designed to model how satellite subsystems behave together. Built in Rust for high-performance and low latency, NeXosim allows teams to test real-time telemetry, protocol handling, timing dependencies, and more. It i s already being used by research teams and startups preparing upcoming missions ranging from 75kg to 750kg [5].
“We’re not building a simulator to show that everything works,” says Adam Chikha, Chief Operating Officer at Asynchronics. “We’re trying to show where things break—how systems interact under real timing and protocol constraints. That’s the only way to know what’s likely to go wrong in orbit.”
The failures plaguing smallsat missions are not mysteries. They’re the result of assumptions left untested, behaviors not modeled, and systems validated in isolation. Reducing failure rates won’t come from building more robust hardware alone. It will require acknowledging that what happens between components matters just as much as what each component does on its own.
Adam Chikha
COO @ Asynchronics
adam.chikha@asynchronics.com
Maciek Mysliwiec
Founder @ Space Agency
maciek@spaceagency.biz
References:
[1] NASA Small Satellite Reliability
https://www.nasa.gov/smallsat-institute/sst-soa/satellite-reliability
[2] Filip Kocian – “Why Do So Many Small Satellites Fail?”, Medium
https://filipkocian.medium.com/smallsat-failures
[3] SpaceNews – “Heavier Smallsats Weigh Down Market Forecasts”
https://spacenews.com/heavier-smallsats-weigh-down-market-forecasts/
[4] ESA Systems Engineering Practice Guide
https://www.esa.int/Enabling_Support/Space_Engineering_Technology
[5] NeXosim on GitHub
https://github.com/asynchronics/nexosim