The European Space Agency is supporting the Czech company Stellar Exploration, within the framework of the ESA InCubed programme, for the implementation of the Earth Remote Sensing via GNSS Radio Occultation (EARS) project. The project involves the definition of a constellation of nanosatellites designed to monitor the Earth’s atmosphere using the GNSS radio occultation method and represents a shift in the Czech space sector towards data-oriented business.

“We see EARS as an important step for Stellar Exploration and for the Czech space sector – a shift from subcontracting to our own data service. Thanks to InCubed and the support of CzechInvest, we can move faster towards our first satellite and commercial operation,” says Jakub Ševeček, CEO of Stellar Exploration.

ESA Commercialisation Support in Project Preparation

An important part of the preparation was the support from ESA Commercialisation Ambassador Czechia at CzechInvest, who worked closely with the Stellar Exploration team to develop a business strategy and provided key input during the preparation of the project application. Their mentoring contributed to the successful evaluation of the EARS project under the ESA InCubed programme and helped align the commercial strategy with the priorities of the Czech Republic.

“Given that the InCubed programme places extraordinary emphasis on commercial viability, we focused with the Stellar Exploration team on the business case when preparing the EARS project application and worked together to fine-tune the so-called InCubed Pitch. In the Czech Republic, we act as a local facilitator between ESA and companies and help projects pass the demanding evaluation process. We are pleased that, thanks to our contribution, Stellar Exploration’s technological excellence and strong business case team have succeeded,” says David Hladík, ESA Commercialisation Ambassador from the CzechInvest agency.

GNSS radio occultation is a method of remote sensing of the Earth using navigation signals from GPS, Galileo, or GLONASS satellite systems. Satellites in low orbit capture these signals as they pass through the atmosphere, where they are bent due to changes in the density of the environment.

The measured data can then be used to derive vertical profiles of temperature, pressure, air humidity, and electron density in the ionosphere. The data obtained in this way is used primarily in meteorology, numerical weather prediction models, and climate research.

Data Processing Directly in Orbit

A key innovation of the EARS project would be the processing of measured data directly on board the satellite. While conventional radio occultation systems transmit raw data to the ground for processing, EARS would instead process the data in orbit and transmit final atmospheric products to Earth, ready for immediate use. This approach would allow results to be delivered to customers within 30 minutes of measurement, significantly increasing their operational value for weather forecasting and other climate services.

The technology being defined by Stellar Exploration plans to achieve an advanced Precise Orbit Determination (POD) system with a relative velocity accuracy of up to 0.1 mm/s. This level of accuracy would be essential for processing radio occultation data directly in orbit and ranks EARS among the most technologically advanced approaches in the field of GNSS radio occultation.

ESA InCubed, the Earth Observation programme managed by ESA Φ-lab, is the commercialisation programme of the European Space Agency aimed at supporting commercially viable projects in the field of Earth observation, covering the entire EO value chain, from upstream to downstream. Since its launch in 2018, the total programme funding reached €325 million (as of December 2025) and it has supported more than 180 activities through which companies have raised private investment funds exceeding €750 million (as of April 2026). The programme enables cooperation between ESA, national delegations, and private companies while maintaining full intellectual property ownership on the part of the recipient of the support.

Advancing the Czech Space Sector

The EARS project represents a step forward for the Czech space industry from subcontracting roles towards building its own systems and commercial operation of data services. Stellar Exploration is defining a model that includes the operation of a satellite constellation and the sale of atmospheric data to customers in the field of meteorology and climate services.

CzechInvest, as the national innovation agency, has long supported the development of the Czech space industry. In addition to its role as ESA Commercialisation Ambassador Czechia, it also operates ESA Business Incubation Centre (BIC) Czech Republic, which since 2016 has been helping start-up entrepreneurs transform space technologies into commercial applications.