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Galaxy classification in Galaxy Zoo

You will learn how to classify galaxies and what is the physics behind the morphology of galaxies.

When you look up the sky, you see stars and galaxies. However, their appearances are not what they are now, but what they were when the light was emitted, because the light needs time to travel to the earth. The light from more distant galaxies takes more time to reach us. In other words, by studying distant galaxies, astronomers can investigate galaxies in the past, when they were younger. In this way, astronomers study evolution of galaxies.

Astronomers have been studying galaxy morphologies over many years. For instance, we found spiral galaxies were bluer and younger than elliptical galaxies.

However, detailed classification of galaxy morphology is still a challenging task. There exist billions of galaxies in the Universe, many of which are too faint for computers to classify. This is one of the few remaining field, where human brain can do better than computers.

In this exercise, you help the astronomers classify them via Galaxy Zoo. Please find and classify three different types of galaxies (e.g., Barred spiral, Spiral, and Elliptical galaxies) based on Hubble’s classification of galaxies, and see how challenging it is.

In the past, a rare important object was found by an amateur astronomer through this exercise.

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Mysteries Of The Universe

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