Structures in the Universe

TL;DR

The universe is highly structured, with galaxies, clusters of galaxies, and superclusters forming intricate patterns due to gravity and other forces.

Transcript

• Good evening, everybody, and happy new year to everyone gathered in this lecture theater. I'd like to welcome you to lecture three in our series on Cosmic Revolutions. And the title of tonight's lecture is Structures in the Universe. Our universe is a richly structured place. Now that may not seem a surprising statement to make on the face of it.... Read More

Key Insights

• 💁 The universe has a hierarchical structure, with clusters of galaxies forming superclusters.
• 🖐️ Rotation plays a significant role in shaping structures within galaxies.
• 🤩 Supernova blast waves can trigger star formation and create voids in the galactic distribution.

Questions & Answers

Q: How do stars form within galaxy clusters?

Stars form within galaxy clusters when dense gas collapses under gravity and ignites fusion. Large masses of gas and the right conditions are necessary for star formation.

Q: What causes the structures in spiral galaxies?

The structures in spiral galaxies are caused by the rotation of the galaxy and the formation of a disc-like structure. The rotation of the gas and stars within the galaxy create spiral arms.

Q: How do elliptical galaxies differ from spiral galaxies?

Elliptical galaxies appear smooth, but they also exhibit rotation. The rotation in elliptical galaxies is not as prominent as in spiral galaxies, but it is still present.

Q: What is the significance of galaxy-galaxy interactions in shaping structures?

Galaxy-galaxy interactions can induce structures in galaxies, such as spiral arms and bars. The gravitational forces between galaxies can distort orbits and cause gas and stars to form structures.

Summary & Key Takeaways

• The universe was once smooth and homogenous, but now it is filled with lumpy and structured formations such as galaxies.

• Stars form within clusters and nurseries, where dense gas collapses under gravity and ignites fusion.

• Spiral galaxies and elliptical galaxies both exhibit rotation, with spiral galaxies forming beautiful disc-like structures.