Sure, Virginia, The Universe is Nonetheless Making Galaxies

Although our universe is previous, chilly, and nicely previous its prime, it’s not achieved making new galaxies but.

Galaxy formation first received began when our universe was just a few hundred million years previous. In these darkish ages the primary stars gathered sufficient materials to set off nuclear fusion and ignite. Slowly over time these clumps of stars discovered one another and started to construct the primary younger protogalaxies. 

Over time these protogalaxies collected extra materials and merged collectively to shortly develop to change into the huge galaxies that sprinkle all through the universe right this moment.

However galaxies are greater than clumps of stars and fuel. They’re additionally deep wells of dark matter, which is the invisible substance that makes up the a lot of the mass of each object within the universe. To make a galaxy you actually begin with an accumulation of darkish matter. That types the gravitational bedrock for regular matter to collect onto and begin forming stars.

The buildup of darkish matter actually solely occurred within the very early universe, and way back shut off. However these concentrations of darkish matter stay right this moment. Proof from simulations and observations tells us that ordinary matter remains to be discovering these pockets and triggering recent rounds of star formation. Which means whereas the seeds of galaxies had been solely laid down as soon as, new accumulations of matter are nonetheless lighting up within the current day cosmos.

It’s true that we’re nicely previous the height of star formation and the heyday of galaxy meeting. That epoch got here and went over 10 billion years in the past. And much into the longer term our universe will increase a lot that this course of will decelerate and finally cease. However the universe isn’t achieved but. For now, we are able to nonetheless get pleasure from a universe stuffed with galaxies and figuring out that new ones are nonetheless approaching the scene.