What's is the Universe made of?
Look around and you might believe that the universe is made entirely of matter – substances that have mass and take up space. We see it almost everywhere.
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by NASA's Goddard Space Flight Center
is licensed under Creative Commons Zero v1.0 Universal
The Universe
Cosmology is the study of the Universe. It doesn't look at small objects, like stars or planets. It investigates the Universe on a large scale.
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This work
by NASA/ESA/G. Illingworth/D. Magee/P. Oesch (University of California, Santa Cruz)/R. Bouwens (Leiden University)/HUDF09 Team
is licensed under Creative Commons Attribution 4.0 International