Science Class 6 Notes Chapter 12 Beyond Earth Curiosity

Notes For All Chapters – Science Curiosity Class 6

Introduction

• Location: Nubra in Ladakh, India, is known for clear skies, making stars easily visible.
• Characters: Yangdol and Dorjay, siblings, are fascinated by the night sky and star patterns.

Stars and Constellations

• Stars: Shine with their own light, and some are brighter than others.
• Constellations: Groups of stars forming patterns, used for navigation in ancient times.
  • Example: Orion (Hunter), Canis Major (Dog), Taurus (Bull).
  • 88 constellations have been officially recognized by the International Astronomical Union (IAU).
  • Pole Star (Polaris): Appears stationary in the north and helps in navigation.
  • Big Dipper and Little Dipper: Well-known patterns. The Big Dipper is part of Ursa Major, and the Little Dipper is in Ursa Minor.

Watching the Night Sky

• • Best conditions: A clear, dark place with no city lights.
  • Use apps: Like Sky Map to find constellations and stars.
  • Preparation: Bring a compass and print out star maps for easy observation.

The Solar System

• The Sun: A star closest to Earth, provides heat and light, and is about 150 million km away.
  • Diameter: 100 times larger than Earth.
  • The Earth and other planets revolve around it.
• Planets: Large, nearly spherical objects revolving around the Sun.
  • Inner Planets: Mercury, Venus, Earth, Mars (rocky surfaces).
  • Outer Planets: Jupiter, Saturn, Uranus, Neptune (mostly gases).
  • Pluto: Reclassified as a dwarf planet in 2006.

Natural Satellites

• Moons: Natural satellites that revolve around planets.
  • Earth’s moon takes about 27 days for a full revolution.
  • Features: Craters formed by asteroid impacts.
  • India’s lunar missions: Chandrayaan 1, 2, and 3 (successfully landed on the Moon’s south pole).

Asteroids and Comets

• Asteroids: Small rocky objects, mainly found in the asteroid belt between Mars and Jupiter.
• Comets: Objects made of dust, gas, rocks, and ice that form a visible tail when near the Sun.
  • Example: Halley’s Comet, visible every 76 years.

The Milky Way Galaxy

• Galaxy: A vast system of stars; the Milky Way contains millions to billions of stars, including our Solar System.
  • Visible as a faint band of light in the night sky.

The Universe

• Beyond the Milky Way: There are many other galaxies. Scientists are exploring exoplanets to find evidence of life, but no proof has been found yet.