Discovering Guide Stars for Enhanced Navigation in Euclid’s Mission

Euclid, ESA’s dark Universe detective, has overcome its navigation woes and is ready for its final testing in full ‘science mode’. The mission, which aims to answer fundamental questions about the nature of our Universe, experienced some hiccups during its initial phase. The most worrying issue was Euclid’s Fine Guidance Sensor (FGS), which at times couldn’t find its guide stars. This was due to interference from the Sun’s protons, stray sunlight, and X-rays.

During the commissioning phase, teams at ESA’s mission control worked tirelessly to resolve these issues. They updated and tested the FGS for ten days in orbit, successfully finding the guide stars. With this problem solved, Euclid will now proceed to the Performance Verification phase, its final test before embarking on its mission in the dark Universe.

The FGS is a completely new development in Europe and plays an important role in Euclid’s mission. It uses guide stars to navigate and maintain the telescope’s precise pointing. Before launch, the FGS was extensively tested on Earth, but real space conditions brought new challenges. Cosmic rays caused false signals to appear in Euclid’s observations, making it difficult for the Sensor to resolve star patterns.

To address this issue, a software patch was developed and tested both on Earth and in orbit. The results were promising, with more stars revealing themselves. The updated software allows the FGS to identify stars more accurately. With this fix in place, Euclid’s Performance Verification phase has restarted, and observations are being carried out correctly.

Euclid’s mission is to delve into the mysteries of dark matter and dark energy, which allegedly make up 95% of our Universe but have never been seen. It will also explore the validity of general relativity on cosmic scales and study the formation of cosmic structures after the Big Bang. By observing one-third of the sky and looking back 10 billion years, Euclid will provide a 3D view of the dark matter distribution and map the evolution of galaxies over cosmic time.

Equipped with one of the most precise and stable telescopes ever launched, Euclid will capture razor-sharp images and deep spectra of the Universe. Over its six-year mission duration, it will change its focus every 75 minutes, pointing more than 40,000 times. This ambitious mission has the potential to revolutionize our understanding of the dark Universe.

Carole Mundell, ESA’s Director of Science, expressed her gratitude to all the teams involved in successfully completing the commissioning phase. She highlighted the exciting phase ahead, where Euclid will be tested in science-like conditions and showcase how it will transform our understanding of the dark Universe.

As Euclid prepares for its scientific survey, scientists and enthusiasts alike eagerly await its first images, which will undoubtedly shed light on the mysteries that have puzzled us for centuries. With its advanced technology and dedicated team, Euclid is poised to make groundbreaking discoveries and reshape our understanding of the Universe.