Galaxies consist of stars, planets, and vast clouds of gas and dust, all bound together by gravity. The largest contain trillions of stars and can be more than a million light-years across. The smallest can contain a few thousand stars and span just a few hundred light-years. Most large galaxies have supermassive black holes at their centers, some with billions of times the Sun’s mass.
Galaxies come in a variety of shapes, mostly spirals and ellipticals, as well as those with less orderly appearances, usually dubbed irregular.

The Classification Of Galaxies | Astronomy

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Let's do English ESL basic listening: focus on hearing. Galaxies consist of stars, planets, and vast clouds of gas and dust, all bound together by gravity. The…