Want high-resolution remote sensing images? Balloons can also help!

Recently, Urban Sky, a U.S. stratospheric balloon remote sensing company, announced the completion of its Series A financing, raising a total of $9.75 million. The company intends to use the funds to expand its commercial imaging business, develop advanced stratospheric technologies, and expand its sensor product portfolio. So, what is Urban Sky's vision for its micro-balloon system? Compared with satellites, what are the characteristics of balloon remote sensing services? What other uses will stratospheric balloons and other aerostats have in the future?

Want to be the SpaceX of the stratosphere

This balloon remote sensing company with only 14 employees was founded in Denver, USA in 2019. The two founders worked at another stratospheric balloon company, Worldview. The balloons used by Worldview are larger and more expensive. It was originally aimed at manned tourism, and then gradually turned to remote sensing services. Urban Sky invented the stratospheric microballoon, a high-altitude remote sensing platform capable of taking visible light and long-wave infrared images. The company aims to use the miniaturization of components, the reusability of balloons, and the advantageous location of the stratosphere to reduce the cost of acquiring remote sensing data over a wide range.

Urban Sky launches stratospheric micro balloons

UrbanSky plans to provide customers with color images with a resolution of 10 centimeters. The company plans to develop higher-resolution visible light cameras and new infrared cameras to capture high-resolution images with a resolution of about 10 centimeters and long-wave infrared data with a resolution of about 3.5 meters, all within the constraints of the sensor payload mass of 2.7 kilograms.

In addition to the natural color optical imagery it currently provides, UrbanSky is also developing near-infrared and long-wave infrared imagery sensors. The sensor, which the startup calls HotSpot, has been demonstrated to monitor wildfires in real time as part of a NASA grant and with support from the U.S. Air Force.

Currently, Urban Sky launches about one balloon per week, and plans to increase the frequency to once every 2-3 days in the future. The new round of financing will also help the company expand its market and expand its flight and imaging business to more than 15 states in the United States, taking very novel and very high-resolution photos of some major metropolitan areas in the United States, with a focus on the Midwest. The company also commercializes this technology for a variety of applications, including insurance analysis, utility monitoring, disaster response, wildfire monitoring, environmental analysis, and capturing high-resolution (less than 10 cm) remote sensing data.

Antonio, the company's CEO, believes that unlike other stratospheric balloon remote sensing companies, the reusable small stratospheric balloon developed by Urban Sky is the first balloon that can be released from the back of a standard pickup truck, and the balloon can be launched from a movable installation position in a few minutes with minimal personnel. This mobile launch system, combined with advanced flight modeling software and a safe, controlled descent, can place these systems precisely in the desired area. "Our vision is to become the SpaceX in the stratosphere," Antonio added, referring to the reusable launch vehicles developed by SpaceX that have brought earth-shaking changes to the rocket launch industry.

Low cost and flexibility are significant advantages

The aforementioned company, WorldVision, believes that the future of balloon business is promising. In the field of remote sensing alone, the global market value will reach $23 billion by 2027, ranging from energy to national security.

Compared with remote sensing satellites in Earth orbit, using stratospheric balloons to obtain remote sensing images has many advantages. On February 3, 2023, Worldview announced that the company intends to shift from balloon tourism to remote sensing technology services, competing with satellite and aviation platforms to provide high-resolution images. After verification by the company, the spatial resolution of the target area can reach 5 to 7 cm. This is much higher than most current remote sensing satellites with a resolution of about 30 cm.

On the other hand, the development, use cost and difficulty of stratospheric balloons are much lower than those of earth orbit satellites. Remote sensing satellites generally need to operate in orbits of several hundred kilometers, while high-orbit remote sensing satellites need to operate in geosynchronous orbits about 35,000 kilometers above the surface to maintain the same rotation period as the earth. This not only requires a lot of preliminary preparation work, but also requires a huge cost to use rockets to launch satellites into orbit, and it also takes a certain amount of time to subsequently obtain and analyze the images taken by the satellite.

As technology develops, the cost of stratospheric balloons will gradually decrease, and they will also be able to be used more quickly and flexibly.

The combination of reuse and mobile deployment of Urban Sky's micro-balloons greatly reduces the cost of use. Due to material engineering requirements, the balloons must be very light, very airtight and low cost. After completing the shooting mission, other companies' disposable balloons usually eject the balloons into the high atmosphere or tear a hole on one side to destroy them. Urban Sky has applied for a patent for a balloon termination and descent mechanism that enables the balloon to return intact and be reused.

In addition to the mobile deployment system, the company has developed a stratospheric flight profile simulator that predicts the flight path of the balloon. Based on the target area, the software works backwards to predict where Urban Sky needs to launch the balloon from.

This reusable balloon enables Urban Sky to reduce the cost of 10-centimeter resolution images to $5-10 per square kilometer. In comparison, the cheapest images from satellite-based earth imaging company Maxar may cost $20-25 per square kilometer, and the resolution is much lower. In addition, stratospheric balloons are more time-efficient, and can flexibly adjust the flight time and shooting area according to customer needs, and can also more conveniently obtain and analyze the captured images.

There is a strong demand for CitySky's color images in multiple markets, including environmental monitoring, property insurance, and oil and gas industries. However, CEO Antonio believes that the company's images are not in direct competition with commercial satellite images, and no customers use the company's images to replace satellite images. The company is also exploring other uses for its small balloons, such as testing network communication systems.

Aerostats have a bright future

Aerostats, including balloons and airships, still have many application scenarios today, such as in meteorological and scientific exploration, space research, military, and commercial activities, and have broad application prospects.

In terms of meteorological and scientific exploration, although there are now advanced means such as sounding rockets, land-based remote sensing, and meteorological satellites, traditional sounding balloons are still the most important direct way to detect high-altitude meteorology. After the sounding balloon is released from the ground, the measuring instruments it carries will transmit data such as temperature, humidity, and air pressure at different altitudes to the radar through signals. The radar calculates wind direction, wind speed and other information through the movement trajectory of the sounding balloon and transmits it to the researcher's computer. It is understood that the sounding balloon can transmit a set of data every second, and this data usually plays an important role in weather forecasts, climate predictions, and scientific research.

The tethered aerostat "Jimu-1", independently developed by the Institute of Space Information of the Chinese Academy of Sciences, was launched near Mount Everest in mid-May 2022, reaching a flight altitude of 9,032 meters, breaking the world record for the altitude of atmospheric science observation by airships. "Jimu-1" has a volume of 2,300 cubic meters. It adopts a streamlined design and can carry scientific detection instruments for vertical profile and airborne observation.

In terms of commercial applications, in addition to traditional tourism and sightseeing services, airships also have considerable market potential in the field of cargo transportation. Existing transportation modes such as railways, roads, and aviation all rely on a large amount of infrastructure construction, while airships, as a heavy cargo air transportation equipment, require almost no ground construction.

In addition, aerostats such as balloons and airships have a wider range of uses. For example, in December 2022, Chongqing's first tethered balloon equipped with a 5G base station successfully completed its test flight. The tethered balloon linked the sky and ground platforms to achieve four emergency support functions: communication support, environmental monitoring, emergency rescue, and high-definition cloud viewing. Compared with traditional drone base stations, aerostats can stay in the air longer, consume less energy, carry more weight, and do not generate noise.

In the future, with the advancement of technology, aerostats may have more and wider uses, bringing new possibilities to their application areas. (Author: Lin Yinzhi, Image source: Urban Sky Company, Review Expert: Jiang Fan, Deputy Director of the Science and Technology Committee of China Aerospace Science and Technology Corporation)