◎◎◎ coronavirus ⪢⪢
Coronaviruses are a large group of viruses. They consist of a core of genetic
material surrounded by an envelope with protein spikes. This gives it the appearance of a crown. 'Crown' in Latin is called 'corona' and that's how these viruses get their name.
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○○○ nebula ⪢⪢
The solar system came into being about 4.5 billion years ago when a cloud of interstellar gas and dust collapsed resulting in a solar nebula, a swirling disk of
material that collided to form the solar system.
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