Stars and stars and star wars

Yesterday I went to the planetarium and some of my old school time memories were revived... some facts that I got to know

1. Pluto is no longer considered the 9th planet of the solar system. Due to some condition which it does not satisfy, it is considered a dwarf planet

2. I always thought that mercury was the hottest planet due to its proximity to the sun. However, I got to know that Venus is hotter than mercury due to the envelope of clouds that lead to greenhouse effect.

3. Sirius or dog star is the brighest of all

4. There are 88 constellations in the night sky

5. Jupiter has around 60 moons

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