Journey through the Cosmos

Closest Star to Our Solar System

• Proxima Centauri is the closest star, located approximately 4.24 light-years away from the Sun.

Major Components of the Milky Way Galaxy

• The Milky Way is a barred spiral galaxy with a central bulge, disk, and halo structure.
• Contains hundreds of billions of stars, including the Sun.
• Features star clusters, nebulae, and various interstellar materials like gas and dust.
• Home to several spiral arms, including the Orion Arm where our solar system resides.

Black Holes: Formation and Characteristics

• Black holes form from the gravitational collapse of massive stars at the end of their life cycle, particularly after supernova explosions.
• Characterized by an event horizon, the boundary beyond which nothing can escape.
• They possess strong gravitational fields that can distort spacetime and affect nearby objects.
• Can be classified into three types: stellar black holes (up to a few tens of solar masses), supermassive black holes (millions to billions of solar masses), and intermediate black holes.

Significance of the Hubble Space Telescope

• Launched in 1990, Hubble has provided deep-space images that have vastly improved our understanding of the universe.
• Its observations helped to determine the rate of expansion of the universe and the existence of dark energy.
• Plays a crucial role in fields like cosmology, astronomy, and astrophysics, offering insights into various celestial phenomena.

Differences Between Meteor, Meteoroid, and Meteorite

• A meteoroid is a small rock or particle from space, typically smaller than an asteroid.
• Upon entering Earth’s atmosphere, a meteoroid becomes a meteor, commonly known as a "shooting star," due to the bright trail created by its high-speed entry and atomic friction.
• If a meteor survives its journey and lands on Earth, it is classified as a meteorite.