Star Size and Measurement Challenges

The video explores the vastness of stars, comparing their mass and volume. It discusses the largest stars by mass, like BAT 99-98, and by size, such as UI Scooty and Stevenson 2-18. The current largest known star is W g64, but measuring these cosmic giants is challenging due to their distance and size. The video emphasizes the ongoing advancements in astronomy to better understand these stars.

What is the estimated number of stars in the Milky Way galaxy?

• Between 50 to 200 billion

• Between 1 to 4 trillion

• Between 100 to 400 billion

• Between 10 to 40 billion

Which star is currently known as the most massive?

• Stevenson 2-18

• BAT99-98

• Betelgeuse

• UY Scuti

What is the estimated age of BAT99-98 compared to the Sun?

• 7.5 million years old

• 4.6 billion years old

• 10 million years old

• 5 billion years old

What was the original estimated size of UY Scuti compared to the Sun?

• 1,700 times the size of the Sun

• 775 times the size of the Sun

• 2,150 times the size of the Sun

• 1,540 times the size of the Sun

What is the theoretical limit for the size of a star according to stellar evolutionary theory?

• 1,000 times the radius of the Sun

• 2,500 times the radius of the Sun

• 1,500 times the radius of the Sun

• 2,000 times the radius of the Sun

How long would it take to travel around Stevenson 2-18 at the speed of light?

• 10.5 hours

• 4 hours

• 9 hours

• 14.5 seconds

What is a significant challenge in measuring the size of massive stars?

• Their proximity to Earth

• Their lack of luminosity

• Their small size compared to the Sun

• Their ever-changing atmospheres and dust clouds

What is the main factor that determines the size of a star?

• Its age and temperature

• Its mass, composition, and evolutionary history

• Its distance from Earth

• Its color and brightness

Which star is currently considered the largest by physical size?

• UY Scuti

• Stevenson 2-18

• WOH G64

• Betelgeuse

What is the estimated radius of WOH G64 compared to the Sun?

• 1,700 times the radius of the Sun

• 1,540 times the radius of the Sun

• 2,575 times the radius of the Sun

• 775 times the radius of the Sun