Astronomers have successfully captured images of faint celestial objects orbiting close to bright stars, a feat previously considered extremely challenging.
The study, led by Thomas Winterhalder of the European Southern Observatory (ESO), combined data from ESA's Gaia space telescope with ESO's GRAVITY instrument, revealing eight hidden companions to luminous stars.
The research team began by scouring Gaia's catalogue of stellar orbits, identifying eight stars suspected of having companions based on subtle wobbles in their paths.
These targets were then observed using GRAVITY, an advanced near-infrared interferometer at ESO's Very Large Telescope in Chile.
GRAVITY's exceptional sensitivity and resolution allowed the team to detect light signals from all eight predicted companions, seven of which were previously unknown. The discoveries include three small, faint stars and five brown dwarfs - objects with masses between planets and stars.
One particularly noteworthy find is a brown dwarf orbiting its host star at a distance comparable to that between Earth and the Sun. This marks the first time such a close-orbiting brown dwarf has been directly imaged.
Winterhalder emphasised the significance of this achievement, stating, "We have demonstrated that it is possible to capture an image of a faint companion, even when it orbits very close to its bright host. This achievement highlights the remarkable synergy between Gaia and GRAVITY."
The study showcases the power of combining space-based and ground-based observations. Gaia's precise measurements of star positions and movements guided GRAVITY to the exact locations for imaging, allowing it to detect objects at incredibly small separation angles - equivalent to viewing a one-Euro coin from 100 km away.
This breakthrough opens up exciting possibilities for exoplanet detection. The research team is now planning to use this technique to search for planetary companions among the stars in Gaia's catalogue.
The study not only revealed hidden companions but also provided valuable data on their masses, ages, and compositions. Surprisingly, two brown dwarfs were found to be less luminous than expected, suggesting they might have smaller companions of their own.
This groundbreaking research demonstrates the potential of combining cutting-edge space and ground-based technologies to unlock new discoveries in our cosmic neighborhood, paving the way for future advancements in our understanding of stellar and planetary systems.
