# Urban Sky

Urban Sky is an American aerospace company headquartered in Denver, Colorado. Urban Sky designs, manufactures and operates small, altitude-stable stratospheric balloons that are primarily used for Earth Observation and remote sensing applications. The balloon systems are the first ever reusable stratospheric balloons and have several unique features including an ability to navigate in the stratosphere, and a novel size (more than 100 times smaller than typical Zero-pressure balloons). About one third of all high altitude balloons flown in 2023 were built or operated by Urban Sky (excluding Latex and weather balloons).

## History

Urban Sky was founded in 2019 with the goal of increasing access to the stratosphere, and reducing the cost of remote sensing through balloon miniaturization and new approaches to balloon control. In 2020 Urban Sky began routine stratospheric operations and became the first company ever to reuse a stratospheric balloon.
In 2022 Urban Sky started routine commercial operations after more than 50 test flights. The initial product Urban Sky released was an aerial imagery product at a resolution of 10-cm. Alongside its visual spectrum imager Urban Sky developed a Long Wave Infrared imaging system funded by NASA for detecting and monitoring wildfires with scanning rates similar to that of satellites with higher resolution. That same year Urban Sky was awarded 3 Air Force Grants to develop new sensor systems including a real-time thermal sensor developed in partnership with the University of Colorado. In 2022 Urban Sky was awarded a National Science Foundation grant to develop more precise placement technology for the balloon systems.
In 2023 Urban Sky was the winner of the National Security Innovation Network challenge for their remote sensing technologies. and that same year started flying communications related missions with a first stratospheric communications flight partnered with goTenna. Two balloons were flown in the demonstration maintaining an altitude of 57,000 feet simultaneously in the 5 hour flight establishing a line-of-site network spanning at least 14,412 square miles.
In October of 2023 the company closed a $9.75M series A funding round to scale imaging operations across the western United States. In 2024 the company announced multiple wildfire campaigns and was announced as one of two companies selected to participate in the NASA firesense campaign and announced a new Long Wave Infrared sensor for early detection and live mapping of wildfires.
As of 2023 the company had raised at least $13.8M in funding rounds that were shared publicly.

## Microballoon technology

Urban Sky Remote Sensing balloons operate in the stratosphere at an altitude of about 20km (about 65,000 feet), and are roughly the size of a car at launch with a payload attached underneath. The balloons grow in volume as they ascend and are roughly 11 times larger in the stratosphere than when they are near the ground. The balloons are propelled by the wind, allowing them to drift over predetermined targets from mobile launch locations depending on season. Urban Sky balloons are the world's first reusable stratospheric balloons. The small balloons fly in the same regulatory category as most weather balloons, limiting payload mass to 2.7 Kg per package.
In 2023 they were operating more than one stratospheric flight per week in the western United States. Based on the 2023 American Institute of Aeronautics and Astronautics Balloon Technical Committee year end report and the StratoCat balloon flight database (which showed collectively 98 high altitude balloon flights flown by other, non-Urban Sky, operators in 2023) the Microballoon type high altitude balloon was the third most prevalent type of high altitude balloon after Latex and weather balloons.