GAIA SPACECRAFT (Syllabus: GS Paper 3 – Sci and Tech)
Context: Recently, the Gaia spacecraft has successfully overcome significant challenges in its mission to map over a billion stars in the Milky Way.
Gaia Spacecraft
- Launched: The Gaia spacecraft was launched by the European Space Agency (ESA) in December 2013.
- Position: It is located 1.5 million kilometers from Earth at the second Sun-Earth Lagrange point (L2).
- Mission Objectives
o Star Monitoring: The spacecraft monitors each of its target stars approximately 14 times per year, charting their positions, distances, movements, and brightness changes.
o Discovery Goals: Gaia is expected to discover hundreds of thousands of new celestial objects, such as extra-solar planets and brown dwarfs, and observe hundreds of thousands of asteroids within our Solar System.
o Quasar and Relativity Studies: The mission is also studying more than 1 million distant quasars and providing stringent new tests of Albert Einstein’s General Theory of Relativity.
o Camera Precision: Capable of resolving the diameter of a human hair from 1,000 km away.
Instrumentation and Data Collection
- Optical Telescopes and Instruments: Gaia contains two optical telescopes and three science instruments to precisely determine star locations, velocities, and to split their light into a spectrum for analysis.
- 3D Galactic Mapping: The spacecraft is creating an extraordinarily precise three-dimensional map of nearly two billion objects throughout our Galaxy and beyond, mapping their motions, luminosity, temperature, and composition.
- Stellar Census: The extensive stellar census provided by Gaia is crucial for addressing a wide range of important questions related to the origin, structure, and evolutionary history of our Galaxy.
