Two large spiral galaxies, known collectively as the Antennae, are staging a spectacular merger. The process draws out long tails of stars from each galaxy, while compressing clouds of gas and dust to give birth to tens of thousands of new stars (shown in the bright red regions). Lanes of dark dust permeate the galaxies, ready to collapse to give birth to even more stars. The merger will take tens of millions of years to longer to complete, and will result in a rather dull remnant known as an elliptical galaxy -- an almost featureless football-shaped agglomeration of stars. [NASA/ESA/Hubble Heritage Team]
We can see our future in the stars. Not our individual futures, mind you, but the future of our home galaxy, the Milky Way.
The future of the Milky Way is visible in a pair of colliding galaxies known as the Antennae. Today, we see them as two bright galactic cores flanked by long streamers of stars that look like the antennae of an insect.
Before the collision began, the individual galaxies were big, beautiful spirals like the Milky Way. A few hundred million years ago, though, the two galaxies passed close to each other for the first time. Their gravity pulled out stars, forming the “antennae.” Gravity also squeezed giant clouds of gas and dust, giving birth to many millions of new stars.
The galaxies looped around each other, then swung even closer together than the first time. This second encounter triggered the birth of even more stars - a process that’s continuing today.
About 50 million years from now, the cores of the two galaxies should merge. Over time, the galaxies will settle down, transforming one of the most dynamic systems in the universe into one of the most boring.
The same fate awaits the Milky Way. In a few billion years, it will merge with the Andromeda galaxy. For a while, the system will look much like the Antennae do today - two galaxies merging to make a single giant family of stars.
The Antennae are in Corvus, the crow, which is in the southeast as night falls. Its brightest stars form a pattern that looks like a sail.
Script by Damond Benningfield, Copyright 2013
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