The star at the center of our solar system
📖 Advanced Vocabulary
📚 Reading — Our Star
The Sun is a star — a massive ball of hot gas located at the center of our solar system. It is composed primarily of hydrogen (about 73%) and helium (about 25%). The Sun is so large that about 1.3 million Earths could fit inside it.
The Sun produces energy through a process called nuclear fusion. In its core, where temperatures reach about 15 million degrees Celsius, hydrogen atoms are fused together to form helium. This process releases enormous amounts of energy in the form of light and heat.
Sunlight takes approximately 8 minutes and 20 seconds to travel from the Sun to Earth, covering a distance of about 150 million kilometers. This energy is essential for life on Earth — it drives weather patterns, ocean currents, and the process of photosynthesis in plants.
The Sun is approximately 4.6 billion years old and is currently in the middle of its life cycle. Scientists estimate that it will continue to burn for another 5 billion years before it eventually expands into a red giant and then shrinks into a white dwarf.
The Sun occasionally produces solar flares — powerful bursts of radiation that can affect satellite communications and power grids on Earth. The Sun also has an 11-year solar cycle during which its activity increases and decreases.
📝 Grammar Review — Everything You've Learned
Throughout this journey, you have learned these English grammar concepts:
🎯 Final Comprehension Quiz
1. What is the Sun primarily composed of?
2. How does the Sun produce energy?
3. How long does sunlight take to reach Earth?
4. How old is the Sun?
5. What are solar flares?
✍️ Writing Exercise
Write 3-5 sentences in English about your favorite planet. Use what you have learned:
- Use "is" and "has" correctly
- Use at least one comparison (bigger than, the coldest, etc.)
- Use at least one connector (because, even though, however)
This is a free writing exercise — there is no automatic grading. Share your writing with your teacher!