Q&A 12: Does the Universe Have a Preferred Spin and More...

TL;DR

Astronomer answers viewer questions on asteroids, black holes, galaxies, and the universe's edge in a cosmic Q&A session.

Transcript

well happy 2017 everyone once again it's time for our questions and answer this is where you ask the questions I'll give you the answers if you want to ask a question just go on to any video on YouTube just put in your question I'll find it collect my favorites and answer them here before we get to that I just want to let you know that we have publ... Read More

Key Insights

• 🥮 Asteroids with moons near Earth can experience dynamic interactions due to gravitational forces.
• 👻 Dark energy's repulsive force is weaker within galaxies, allowing gravity to maintain their stability.
• 🙂 Distant galaxies emit radiation, making them visible from millions of light-years away.
• 💥 The Milky Way and Andromeda collision will mainly involve scattered solar systems rather than direct collisions.
• 🖤 Black holes emit radiation when actively feeding on matter and become dark once inactive.
• 🙂 Observing Planet 9 and other distant objects is challenging due to their low light reflection and distance from the Sun.
• 💽 Galaxy orientation and rotation direction within accretion disks are random across the universe.

Questions & Answers

Q: Can asteroids with moons near Earth collide or separate due to gravitational interactions?

Yes, close encounters of asteroids with moons near Earth can lead to chaotic interactions, potentially resulting in collisions or separations between the bodies.

Q: What type of radiation do black holes release? Can we detect it easily?

Black holes emit radiation while consuming matter but are dark once inactive. Detecting Hawking radiation from black holes is challenging due to its sporadic release of particles.

Q: Why are distant galaxies visible but not closer objects like Planet 9?

Galaxies emit abundant radiation, making them visible from millions of light-years away. In contrast, reflective objects like Planet 9 are harder to detect due to low light reflection and distance from the Sun.

Q: How will the Milky Way and Andromeda collision affect solar systems' paths?

When the Milky Way and Andromeda collide, solar systems are unlikely to collide directly, but gravitational interactions may alter their paths within the galaxies or scatter them into intergalactic space.

Q: Why do galaxies not collapse or fly apart despite dark energy's repulsive force?

Dark energy's repulsive force is weak within galaxies compared to gravity, which holds them together. Galaxies remain stable due to the dominance of gravitational forces on their stellar and gas components.

Summary & Key Takeaways

• Asteroids with moons can have chaotic interactions near Earth, causing collisions or separations.

• Black holes only emit radiation when consuming material, making them dark once inactive.

• Galaxies' vast distances and emitted radiation make them visible, unlike distant reflective objects like Planet 9.