Study Finds Sgr A* Black Hole's Actual Age and How It Was Formed

Summary

This video explores the recent findings about Sagittarius A*, the Milky Way's central black hole. The study by Wang and Jang suggests that the black hole's unusual spin is due to a massive collision with another black hole approximately 9 billion years ago, likely from the Gaia Enceladus Galaxy. This discovery supports the hierarchical black hole growth theory, providing evidence for how supermassive black holes can reach enormous sizes and potentially allowing us to predict future mergers.

Takeaways

• 🌌 The video discusses recent discoveries about the central black hole of the Milky Way, Sagittarius A*.
• 📸 The iconic Event Horizon Telescope captured an image of this black hole, which led to a Nobel Prize.
• 🔍 A study by Wang and Jang focuses on how Sagittarius A* was most likely formed and when it was formed.
• 🌟 The researchers potentially discovered the origin story of Sagittarius A*, answering questions about massive black hole formations.
• 🌌 The black hole in the Milky Way is relatively close to Earth, allowing detailed observations not possible with more distant black holes.
• 🌠 Observations have revealed that Sagittarius A* has unusual emissions and occasional major eruptions.
• 🌪️ The energy from the black hole sometimes forms 'chimneys' and exhaust vents, but these do not significantly contribute to its mass.
• 🌌 Sagittarius A* is not growing significantly from the destruction of stars, suggesting it must have grown to its current size through other means.
• 💥 The study suggests that Sagittarius A* grew through a massive black hole collision, a process previously lacking evidence.
• 🌀 The black hole's unusual spin is evidence of a past collision, likely with the Gaia Enceladus Galaxy around 9 billion years ago.
• 📈 This discovery supports the hierarchical black hole growth theory and suggests that we might witness similar collisions in the future.

Q & A

What is the name of the black hole at the center of the Milky Way galaxy?

The black hole at the center of the Milky Way galaxy is called Sagittarius A*.

What recent discovery about Sagittarius A* is discussed in the video?

The recent discovery discussed in the video is how Sagittarius A* was most likely formed and when it was formed, based on a study by Wang and Jang.

What is the mass of Sagittarius A* compared to other black holes?

Sagittarius A* has a mass of just over 4 million solar masses, which is relatively small compared to other black holes like the one in the middle of the M87 galaxy, which is closer to 6 billion solar masses.

How far away from Earth is Sagittarius A*?

Sagittarius A* is approximately 26,000 light years away from Earth.

What types of emissions can be observed from Sagittarius A*?

Sagittarius A* produces emissions that can be observed in X-rays, infrared, and radio wavelengths.

How often does Sagittarius A* have major eruptions?

It is believed that Sagittarius A* has at least one major eruption every few hundred years.

What is the role of the 'chimneys' discovered in the vicinity of Sagittarius A*?

The 'chimneys' are structures through which a lot of energy from the black hole is guided and eventually released all at once.

What evidence suggests that Sagittarius A* grew through collisions?

The evidence comes from the spin of Sagittarius A*, which is unusual and misaligned with the rest of the Galaxy, suggesting it resulted from a massive collision.

What was the mass ratio of the black holes in the collision that formed Sagittarius A*?

The mass ratio of the black holes in the collision that formed Sagittarius A* was about 4 to 1.

How long ago is the Gaia Enceladus Galaxy believed to have merged with the Milky Way?

The Gaia Enceladus Galaxy is believed to have merged with the Milky Way approximately 9 billion years ago.

What is the hierarchical black hole growth theory mentioned in the video?

The hierarchical black hole growth theory suggests that massive black holes grow by colliding and merging with other black holes.