What happens if two galaxies collide?
The average distance between bright galaxies is only about 20 times their size, so over the history of the Universe (14 Billion years), we expect that most bright galaxies will have had at least one close gravitational encounter with a neighboring galaxy. This lecture explores what happens when two galaxies undergo interactions ranging from passing tidal interactions to head-on collisions, all the way to multiple collisions and galaxy “cannibalism” in t…
A collision of galaxies rocks the imagination. You would expect it to create the biggest bang in the universe and shatter billions of suns and their planets. There is indeed a big bang, but astronomers say that stars and solar systems are not annihilated in the cosmic collision. The countless galaxies Of the cosmos are separated by vast distances. What’s more, We are told that, the universe is expanding, and the spaces between the galaxies are increasing at fantastic speeds. A collision between two galaxies seems unlikely, but the rare event does occur. We can perhaps imagine the staggering event if We stretch our minds to grasp the dimensions of our own galaxy. If a spacecraft could maintain a speed of 70 million miles an hour, it could cross the big pinwheel in about 800,000 earth years. The galaxy contains about 100 billion widely separated stars. The spaces between them are strewn with immense clouds of gas and cosmic dust. Our spacecraft might tangle with some of these cosmic clou
