NASA | Swift Finds 'Missing' Active Galaxies

The video explores the presence of supermassive black holes in galaxies, which emit X-rays. It highlights the role of NASA's Swift satellite in discovering hidden black-hole-powered galaxies that contribute to the cosmic X-ray background. The video explains how viewing angles affect the detection of these black holes and discusses the historical context of galaxy mergers that activated black holes, leading to a peak in the X-ray background when the universe was younger.

What is a significant characteristic of supermassive black holes in galaxies?

• They are smaller than the Sun.

• They have millions of times the Sun's mass.

• They are always inactive.

• They emit only visible light.

How do astronomers detect emissions from active black holes?

• By counting the number of stars around them.

• By observing them only during the day.

• By measuring the sound they produce.

• By analyzing the angle of view and the surrounding disk.

What role does NASA's Swift satellite play in black hole research?

• It measures the temperature of black holes.

• It builds a sensitive X-ray map of the sky.

• It captures images of black holes in visible light.

• It records the sound of black holes.

What historical event increased the activity of black holes?

• The extinction of dinosaurs.

• Frequent galaxy mergers about seven billion years ago.

• The formation of the solar system.

• The Big Bang.

What is the significance of the cosmic X-ray background peak?

• It marks the beginning of the solar system.

• It indicates the end of the universe.

• It shows the time when galaxy mergers were frequent.

• It represents the birth of the first stars.