Indira Gandhi Planetarium, Lucknow Veer Bahadur Singh Planetarium, Gorakhpur        Aryabhatt Planetarium, Rampur


Mars, Earth's outer neighbor, is the fourth planet from the Sun. Mars' bright appearance and reddish color stand out in the night sky. Impressive surface features such as enormous volcanoes and valleys are frequently obscured by huge dust storms.
It has an orbital period equal to 687 earth days and a rotational period equal to 24hrs 37mins and 22.6 seconds. Mars has a very eccentric orbit that can vary from 249 million km to 207 million km.  

Internal Structure of Mars:
The core covers half the inner radius of the planet (1520-1840 kms) consisting primarily of iron with about 14-16% sulphur. This iron sulfide core is partially or completely fluid.
The core is surrounded by a silicate mantle that formed many of the tectonic and volcanic features on the planet.
The average thickness of the planet's crust is about 50 km i.e. the crust of Mars is about 80 km thick in the southern hemisphere but only 35 km at the north.

Atmospheric Composition of Mars:
Surface Pressure   0.7-0.9 kPa  
Components   Percentage Composition  
carbon dioxide   95.72  
nitrogen   2.7  
argon   1.6  
oxygen   0.2  
carbon monoxide   0.07  
water vapour   0.03  
nictric oxide   0.01  
neon   2.5 ppm  
krypton   300ppb  
formaldehyde   130ppb  
xonon   80ppb  
ozone   30ppb  
methane   10ppb