Black Holes and Telescopes Concepts

What two things are needed to see light from a distant star that is outside the visible range?

• A series of optical telescopes and a regular clock.

• A series of radio telescopes and a very accurate clock.

• A single large telescope and a stopwatch.

• Only the human eye and a clear night sky.

Why do faint signals from a distant star arrive at slightly different times at different telescopes on Earth?

• The telescopes are not all pointed in the same direction.

• The signals travel at different speeds.

• The telescopes are located at slightly different distances from the star.

• The Earth is constantly moving.

What is the name of the collaboration that took the first image of a black hole?

• The Stellar Observatory Project

• The Event Horizon Telescope Collaboration

• The Mauna Kea Telescope Array

• The Supermassive Black Hole Initiative

How much more massive is the black hole in the M87 galaxy compared to our Sun?

• About 6.5 million times

• About 6.5 billion times

• About 55 million times

• About 55 billion times

What is the "Event Horizon" of a black hole?

• The bright orange ring of light around it.

• The hot swirling gas that produces photons.

• A point of no return where nothing can escape.

• The center of the M87 galaxy.

Why is it difficult to see black holes with regular telescopes?

• They are too far away.

• They are too small.

• They do not produce visible light.

• They are hidden behind stars.

What type of light waves did the Event Horizon Telescope use to image the black hole?

• Gamma rays

• X-rays

• Visible light

• Radio waves

What is the main challenge with using radio waves to create a sharp image?

• Radio waves are too weak.

• Radio waves have very long wavelengths.

• Radio waves are blocked by Earth's atmosphere.

• Radio waves travel too slowly.

How does the Event Horizon Telescope achieve a very high-resolution image of a black hole?

• It uses one very large telescope in space.

• It combines signals from many telescopes around the world.

• It uses special lenses to magnify the image.

• It waits for the black hole to get closer to Earth.

What kind of clock is used by the Event Horizon Telescope to keep time very precisely?

• An atomic clock

• A quartz clock

• A hydrogen maser clock

• A pendulum clock