Space is EXCITING. Space is THRILLING.  And of course, it's full of challenges; it’s not a Sunday villa, beach vibes by any means. But that is exactly the point. Space challenges humanity to bring out the best of what we’ve got to tackle the challenge at hand.

From Low Earth Orbit (LEO) to deep space, we've been able to harness these regimes to connect families across the globe and peek at galaxies hundreds of millions of light-years away. There's endless potential — perhaps unexpectedly in the frontier closest to home.

Very Low Earth Orbit (VLEO) is the piece of space between approximately 100-400km, effectively sitting atop the Kármán line. This dividing line is the established definition of space because it transitions to an area where traditional aircraft can no longer effectively fly - and the distance marker humans have to clear to officially be an "astronaut", according to the FAA. Anything staying in orbit above the Kármán line needs a propulsion system that doesn’t rely on lift traditionally generated by Earth’s atmosphere — the “air” becomes less air and more general atmosphere, and the usual expectations around "flight" start to crumble.

A few LEO systems operate slightly above the VLEO boundary, most notably the International Space Station, which flies at a median altitude of 415 km. That big ol’ station hugs this edge between LEO and VLEO because it’s just high enough to not have to deal with a lot of the challenges of VLEO, while still being as close as possible to the Earth so our rockets and astronauts can get there… at least most of the time.

Cue the obvious question: what makes VLEO so different that historically, very few satellites have even tried to operate at these altitudes? Here are the heavy hitters, any of which would deter a reasonable person or company:

High drag

Satellites in orbit do not operate in a perfect vacuum. While the traditional mixture we think of as air ends around the Kármán line, the gases that make up Earth’s atmosphere extend upwards several hundreds of kilometers, and the distance where the Earth’s atmosphere stops having a noticeable effect is loosely defined. Due to this, all spacecraft that orbit in a Low Earth Orbit are traveling through atmosphere to some degree.

Atmospheric density decreases exponentially as altitude increases. Beyond ~80 km, atmospheric density is very low and the atmosphere can no longer be considered a continuous gas or fluid but instead acts as a rarefied gas - a free molecular flow. Spacecraft traveling through this tenuous atmosphere experience aerodynamic forces and torques that can become significant and become a major design driver for missions that fly under 400 km. Especially when the sun is highly active and occasionally ejects solar flares.

Our sun is highly active and specifically during solar flares, we see an increased amount of these forces. In 2022, 40 Starlink satellites de-orbited due to increased drag during a solar flare event. So while flying lower enables you to collect higher resolution data, your system must have a means for compensating for the very dynamic environment.

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High Atomic Oxygen (AO) environments

One of the primary causes of material degradation in LEO is exposure to atomic oxygen (AO), the most problematic atom in the upper atmosphere. Harkening back to high school chemistry class, you may have learned about how much oxygen loves to bond with things (rust has entered the chat).  Well atomic oxygen is an un-bonded lone oxygen atom, which means it’s going to try and react and bond with just about anything it touches. Kind of a problem. In VLEO, Atomic Oxygen likes to double down even more. When AO atoms collide with an orbiting spacecraft, the relative velocity is 7 to 8 km/sec (16000 - 18000 mph) and the collision energy is 4 to 5 eV per atom. Under these conditions, atomic oxygen may initiate a number of chemical and physical reactions with exposed materials. These reactions contribute to material degradation, surface erosion, and contamination - outer space slowly weathering down a satellite - and oh by the way, further increasing drag!

Fun tidbit: early Space Shuttle flight experiments found that hydrocarbon polymers exposed to the LEO environment would gradually erode as a result of atomic oxygen exposure. The atomic oxygen interacts with the polymers causing the surface to convert to volatile oxidation products. The erosion rates varied based on the polymer, but thanks to NASA there's a plethora of data on varying material degradation due to AO. Data we’ve put to great use!

Reduced access windows and challenging agility requirements

Flying at a lower orbit means you are that much closer to the always-rotating Earth — and so, the relative angular rates between the satellite and the Earth are much faster.

For example, at an altitude of 250 km, a satellite needs to move itself at up to 1.78°/sec to capture an image of a location that zips by underneath the orbiter. If you want to hold over that point on the ground, then your satellite needs to be able to move itself that fast. If you’re an agile scanning system like Albedo, there is an additional variable X°/sec scan rate you need to be capable of achieving on top of that. And to move between image locations swiftly as the satellites fly by in VLEO, re-targeting acceleration becomes more important too. A typical New Space microsatellite, or even agile CubeSats, typically have <1.0°/sec rate and <0.1°/sec² acceleration capability, aka how fast the satellite can re-position or follow something on the earth. These small sats would not be able to look at multiple targets, or possibly even one location on the earth as the ground moves quickly out of view. Actuators, sensors, data, comms, link budgets and control laws must all be uniquely designed for this high agility regime.

Albedo is designed for 10 cm in VLEO, not the other way around

The most important thing when starting a company is to solve a real problem, then identify the best solution within the solution space. We founded Albedo on the idea that aerial-quality imagery from space would be a game-changer and discovered that operating in VLEO was the best way to achieve that. The hard problem is figuring out how to pack together both a high performance optical payload and a high performance satellite bus, all while flying in VLEO.

To solve this, Albedo took a first principles approach - in the world of bespoke satellite design, Albedo leans more American Ford/Shelby style than Ferrari. We bring precision, muscle, and pure performance to overcome the challenges listed above, rather than trying to finesse any one aspect of the problem and end up with something either extremely expensive or bespoke but less mission-capable.

Through this, we are able to achieve both significant cost reduction and overall product quality improvement. When we evaluated smaller, more finessed aerodynamic architectures, none of them were suitable for achieving better than 30 cm imagery. To achieve our mission, we needed to start from the beginning.

First Principles engineering

Something to consider about specialized aerodynamic looking designs seen in academic VLEO studies: why are they shaped that way? What problem did they see and why did they choose that specific path? Without getting into Albedo's secret sauce, we approached this problem using first principles engineering at its finest. If you have a small force to overcome, if you have a bit of velocity to regain, if you have a bit of drag causing all of these things - what can you do to solve it? In a very similar vein as car design, there are many solutions to making cars both energy efficient, sleek, powerful, and capable - all without focusing on a single design point that might drive every design to look like a tear drop or an airplane.

Albedo is the muscle car of the Earth Observation industry. Raw power, performance, and hardcore engineering. This is the American way of operating in VLEO and collecting native 10 cm imagery.

To overcome dynamic drag, our sleek exterior composition is resistant to atomic oxygen effects and low drag in nature. Albedo has built into our FSW an autonomous protect mode that allows us to maintain our orbit during all times, including unexpected solar events. We will be alive and kicking with a 4 year mission life on average, and sometimes beyond! With highly efficient electric propulsion units, high performance GNC sensors and actuators, and a world class control system, our satellite has been designed  to collect hundreds of thousands of square kilometers full of 10 cm imagery for our customers. Need a pic of both Denver & Boulder? We can grab both, in one satellite pass. To top it off, we did it all about 100x cheaper than experts speculated 5 years ago, and we did it all with our customers front and center in our mind.

Albedo’s Precision Platform

Albedo's spacecraft, which we've coined as the Precision Platform, provides a highly-agile, highly-stable foundation to support ultra-high resolution data collection. While we’re starting with an optical payload for Clarity-1, we've built a modular interface to ensure the Precision Platform can accommodate any high-performance payload. The team at Albedo has spent decades architecting both high performance payloads and satellite systems from scratch, and we’ve built the spacecraft of our dreams to handle any mission in VLEO or beyond. TL;DR; this is our version of a COTS bus - a powerful, opinionated infrastructure to collect and disseminate ultra-high resolution from space, at a price point that’s unmatched.

Above and beyond just operating in VLEO, the 10cm problem is no easy feat. A platform to retain the level of resolution your satellite has resolved must be built to meet the challenge. This is why we have designed our GNC suite to take advantage of modern robotics control theory, precision GNC hardware, and the deepest understanding of how control flows into mission MTF.

We’ve architected our VLEO technology to be extensible to other modalities, as many missions benefit from being 2x as close to the earth. For example, LIDAR reaps a 16x benefit when you cut altitude in half. In any modality, more aperture is goodness², so we built the Precision Platform to fly a big telescope that can catch a lot of photons across all parts of the Electro-Magnetic spectrum.

Mission First

While a lot has changed at Albedo, our mission has always stayed the same: collect aerial-quality imagery from space. VLEO just happened to be the best way to do that. The orbit is an unforgiving place, where mistakes are amplified and the margin for error is razor-thin. But Albedo keeps in mind a phrase I hold dear to my heart: Trying to change the world ain’t for the faint of heart. Deep space is thought of as the final frontier, but there's a closer, equally as harsh frontier. The scene is set and the explorers are ready: may the best pioneer win!

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