Future black hole probe makes discovery about its first observation

GRAVITY is the most powerful instrument installed on the Very Large Telescope Interferometer (VLTI), the world’s most advanced infrared telescope, operated from ESO’s observing site at Paranal, Chile. GRAVITY's mission is to zoom in on black holes. This week, ESO announced the successful first observations of GRAVITY, marking a crucial milestone in the commissioning of the instrument within the VLTI. Researchers at CENTRA , the Multidisciplinary Center for Astrophysics of the Universities of Lisbon and Porto are on the team that built this powerful instrument.

Established as a science priority by ESO, GRAVITY combines the light from several telescopes to form a virtual telescope up to 200 metres across. It uses a technique known as interferometry, which allows astronomers to detect much finer detail in astronomical objects than is possible with a single telescope. In the first observation GRAVITY has already made a small discovery: one of the stars in the star-shaped cluster located in the heart of the Orion region is a double star. 

The Portuguese CENTRA team built GRAVITY's acquisition chamber, which follows the astronomical objects and corrects for residual irregularities caused by Earth's atmosphere and by small mechanical vibrations on the rays of light that are combined from the four telescopes. This feature underlies GRAVITY's exceptional accuracy.

The Portuguese researchers are now preparing to use GRAVITY to investigate the black hole in the center of our galaxy and the origin of stars and planets, amongst other scientific questions. The participation of the CENTRA team in the GRAVITY consortium was partially merged by the FCT.

Images, from top to bottom:

• GRAVITY — future black hole probe
• GRAVITY discovers new double star in the Orion Trapezium Cluster

(Credits: European Southern Observatory – ESO)