How Big is The Universe?

Introduction

This tutorial explores the vastness of the universe as depicted in the video "How Big is The Universe?" by Science Time. We will take a step-by-step journey from Earth to the edges of the observable universe, gaining perspective on cosmic distances and our place in the cosmos.

Step 1: Understand Earth and Its Neighbors

• Start from Earth: Recognize our home planet as a blue and green orb in the vastness of space.
• Zoom to the Moon:
  • Distance from Earth: Approximately 238,855 miles (384,400 kilometers).
  • Consider the Moon's size and its role as our closest cosmic neighbor.

Step 2: Explore the Solar System

• Journey to the Sun:

  • Distance from Earth: About 93 million miles (150 million kilometers).
  • Understand the Sun's significance as the central star of our solar system and its impact on Earth.

• Visit Mars:

  • Distance from Earth varies between 34 million miles (54.6 million kilometers) and 250 million miles (401 million kilometers) depending on their positions in orbit.
  • Note Mars as a point of interest for future exploration.

• Reach Neptune:

  • Distance from Earth: Approximately 2.7 billion miles (4.3 billion kilometers).
  • Acknowledge Neptune as the furthest planet in our solar system.

Step 3: Venture Beyond the Solar System

• Voyager 1 Probe:

  • Distance from Earth: Over 14 billion miles (over 22 billion kilometers).
  • Recognize Voyager 1 as the first human-made object to enter interstellar space.

• Discover the Oort Cloud:

  • Theoretical distance: Estimated to be between 1,000 to 100,000 AU (astronomical units).
  • Understand the Oort Cloud as a distant region filled with icy bodies.

Step 4: Explore Nearby Stars

• Alpha Centauri System:
  • Distance from Earth: About 4.37 light-years.
  • Familiarize yourself with the fact that Alpha Centauri is the closest star system to us.

Step 5: Navigate Through the Milky Way

• Position in the Milky Way:

  • Recognize that our solar system is located in one of the spiral arms known as the Orion Arm.

• Local Group:

  • Learn about the Local Group, a collection of more than 54 galaxies, including the Milky Way.

Step 6: Understand Cosmic Structures

• Virgo Supercluster:

  • Understand that this supercluster contains over 100 galaxy groups and clusters, including the Local Group.

• Laniakea Supercluster:

  • Explore the concept of Laniakea, which encompasses the Virgo Supercluster and others, indicating the vast scale of the universe.

Step 7: Confront the Observable Universe

• Great Attractor:

  • Consider the mysterious gravitational pull of the Great Attractor, which influences the motion of galaxies.

• Boundaries of the Observable Universe:

  • Understand that the observable universe is about 93 billion light-years in diameter.
  • Ponder what lies beyond this observable limit and the implications for our understanding of the universe.

Conclusion

This tutorial has taken you on a vast journey, from Earth to the observable universe, highlighting the immense distances and structures that exist in space. Key takeaways include the relative distances to celestial bodies, our position in the Milky Way, and the larger cosmic structures. To deepen your understanding, consider exploring more about each of these astronomical bodies and phenomena through further research or additional videos.