Astronomy is on the brink of a groundbreaking leap with the introduction of PhotSat, a 12U CubeSat set to unlock the secrets of ultraviolet (UV) light from the cosmos. Traditionally, our view of the UV realm has been severely hindered by Earth’s atmosphere, which effectively blocks the majority of UV photons, especially in the UV-C and UV-B spectrums (wavelengths between 100-315nm). Now, a consortium from the Institut d'Estudis Espacials de Catalunya (IEEC) is stepping up to provide unprecedented insights into this hidden universe.

PhotSat, positioned around 500 kilometers above the Earth’s surface, is designed to scan the entire sky every few days, capturing both UV and visible light. This CubeSat is not just any satellite; it houses a sophisticated 6U payload equipped with dual cameras, an X-band antenna, and an innovative control unit tailored explicitly for UV observations.

What makes PhotSat truly remarkable is its ability to provide timely updates that could transform our understanding of the cosmos. With high-frequency observations, it aims to track exoplanet transits, identify transient cosmic events like gamma-ray bursts and supernovae, and monitor the ever-changing conditions of space weather. The data generated by PhotSat will serve as a vital resource for telescopes on Earth and in space, enhancing their observational capabilities.

One of the standout technologies onboard PhotSat is the siderostat, a precision mirror control system that enables the satellite to capture panoramic images of the sky. By precisely maneuvering its mirrors, PhotSat can focus on different sky sections, enabling it to photograph approximately 14 arcseconds of the sky per capture, with a remarkable stability of around 5 arcseconds.

Strategically positioned at a 45-degree angle from the Sun, PhotSat will minimize interference from solar UV rays, ensuring high-quality data collection. Over its mission duration, it aims to scrutinize around 40 million of the brightest celestial objects, primarily stars. Excitingly, PhotSat is expected to detect nearly 3,000 transient events each year, providing invaluable alerts for larger telescopes to follow up with detailed investigations.

As part of its scientific mission, IEEC is currently on the lookout for collaborations to support the project financially and technically. With a targeted launch year of 2026, PhotSat is poised to mark a significant milestone not only for the IEEC but for the entire European scientific community, enhancing our grasp of ultraviolet observations.

This innovative initiative promises to be a game-changer in our quest to explore the universe, shedding light on unexplored dimensions of astronomy and paving the way for future discoveries that could reshape our understanding of the cosmos.