The fastest planet, the Mercury.

 The Mercury is the closest planet from the sun. So powerful sunlight eclipse the Mercury, so we watching the Mercury is very hard and dangerous. This fast planet named "Mercury" because Mercury is the fastest god in Greek and Roman mythology. Mercury is simillar with moon. Because it has no atmosphere and it is desert like moon. Let's learn about the Mercury.

1.Mercury's orbital characteristic

 The Mercury is close from sun. The Mercury is about 46001272km to 69817079km from the Sun. The mercury's orbit is ellipse. It is not simillar to circle.

Aphelion:69817079km
Perihelion:46001272km

It's orbital period is about 88 days. It's rotation period is 58 days.

2.Mercury's physical characteristic

The mercury is very samll. It's surface area is 0.147 x Earth's surface area. And its volume is 0.056 x Earth's volume. And its mass is 0.055 x Earth. But its mean density isn't samll. Its mean density is 5.427 g/cm³  So it doesn't have enough gravity that it can't have enough atmosphere. So it changed desert like moon.


Volume:6.083×10¹⁰ km³
Mass:3.3022×10²³ kg
Surface area:7.48×10⁷ km²
Mean density:5.427 g/cm³


And it doesn't occurs greenhouse effect on the Mercury, so the Mercury's night is very cold.

Night mean temperature:103K
Mean temperature:440K
Day mean temperature:623K

3.Mercury's atmosphere

 It has a tiny atmosphere

42% oxygen
29% soduim
22% hidrogen
6.0% heluim
1% others