Gaia Mission: Recently, the European Space Agency (ESA) shut down its space observatory mission Gaia.

• About Gaia Mission: Launched in December 2013, Gaia has been instrumental in charting the Milky Way galaxy, revealing its past and estimating its future.

o Originally named Global Astrometric Interferometer for Astrophysics (GAIA), later renamed Gaia.

o Designed for astrometry – mapping the cosmos by precisely measuring locations and movement of stars and celestial bodies.

o Positioned at Lagrange point 2 (L2), 1.5 million km behind Earth, allowing an unobstructed view of space.

o Equipped with twin telescopes directing light onto a billion-pixel digital camera, the largest flown in space.

o Instruments: Astrometer (Measures star positions and movements) → Photometer (Analyses brightness and colours) → Spectrometer (Determines chemical composition and velocities)

• Discoveries by Gaia: Created a precise 3-D map of the Milky Way galaxy and projected its future changes.

o Confirmed the galaxy’s central bar and spiral arms, and revealed that its disc is warped and wobbles due to past collisions with satellite galaxies.

o Discovered a new kind of black hole, including one near Earth, detected only by gravitational effects.

o Identified 150,000+ asteroids, mapped their orbits, and projected those that may threaten Earth.