OCR Physics Space Revision Notes

• 1The universe is expanding, as demonstrated by redshift observations.
• 2Gravity governs the motion of celestial bodies and the formation of orbits.
• 3Stars undergo a life cycle, evolving from nebulae to main sequence stars, and eventually to red giants or supernovae.
• 4Black holes are regions of spacetime with gravitational pull so strong that nothing can escape from them.
• 5Exoplanets are planets outside our solar system, and their detection methods include the transit method and radial velocity method.

Space is the vast area beyond Earth that contains all the stars, planets, and galaxies. Gravity keeps planets in orbit around stars, and stars live through different stages, from birth in nebulae to death as supernovae or black holes. Scientists study these celestial objects to understand how the universe works and how it has changed over time.