'Ghosts of the radio universe': Astronomers have discovered a slew of faint circular objects
Radio astronomers see what the naked eye can't. As we study the sky with telescopes that record radio signals rather than ...
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2D Shapes
This song is all about different types of flat shapes ... A square and a rectangle, a circle and a triangle. Images of the shapes appear as they are mentioned in the song. GIRL 1: (singing ...