Smallest planet in the universe



There are a couple of different ways to measure how “big” something is. The first is an object’s mass (how much matter it contains) and the second is its volume (how much space it takes up). The smallest planet in regards to both mass and volume is Mercury — at 4,879 km across and 3.3010 x 1023 kg, this tiny world is nearly 20 times less massive than Earth, and its diameter is about 2½ times smaller. In fact, Mercury is closer in size to our Moon than to Earth.
(In case you're wondering, though, Mercury is still significantly larger than the dwarf planet Pluto: Pluto's equatorial diameter is just 2,302 km, about half Mercury's width.)
Mercury is a tiny black dot as it transits the Sun in 2006.
Fred Espenak

Subsection: General Knowledge
Section: Student Zone

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Last edited REHAN - 8 Oct 2021, 12:43
Latest Activity: 8 Oct 2021, 12:43