Relative Size of Planets and the Sun

How much do you know about Mars and its role in the solar system? Take this short quiz to find out.

Mars in the Solar System Quickie Quiz:

Mars is considered:

A) a major planet in the solar system
B) a dwarf planet in the solar system
C) the smallest planet in the solar system
D) an inferior planet in the solar system

A: Mars is one of the major planets in the solar system.  The dwarf planets are small bodies that are still big enough to hold a spherical shape. These include 1 Ceres, 90482 Orcus, 28978 Ixion, among others. Pluto was downgraded to a dwarf planet in August 2006.

Mars is part of:

A) The inferior planets
B) Zone 1, the inner planets
C) Zone 2, the outer planets
D) Zone 3, the outer solar system

B: The inner planets are within the solar system’s asteroid belt and include Mercury, Venus, Earth and Mars. The rest of the major planets are outer planets. Mercury and Venus, which lie within Earth’s orbit, are inferior planets.

Mars is the only planet that:

A) is part of the Kuiper Belt.
B) is close enough to be explored by Earth probes.
C) has a name with Germanic, not Greco-Roman origins
D) has a vast quantity of iron oxide on its surface

D: Pluto is part of the Kuiper Belt, a ring of ice thought to be the origin of comets. Space probes from earth have already explored Saturn, Mercury, Jupiter, Venus, Uranus and Neptune, as well as Mars. Earth is a Germanic name, although it is known in many languages as Terra after the Roman goddess. The vast quantity of iron oxide on the surface of Mars is what gives the Red Planet its fiery colour.

Mars is different from the Earth in that it has:

A) no history of volcanic activity
B) no polar ice caps, ice and snow
C) no seasonal temperature changes
D) lower atmospheric pressure

D: Earth and Mars both have volcanoes, seasonal temperature changes, polar ice caps, ice and snow (although the “snow” on Mars is different from that on Earth). But the Red Planet has much less-dense an atmosphere than the Earth.  Wind-storms on Mars can kick up huge dust-storms, but the wind doesn’t have much force behind it due to the low atmospheric pressure.

4. Mars is most similar to:

A) Venus
B) Jupiter
C) Earth
D) Saturn

C: While Venus is the closest planet to the Earth in both proximity and size, it is also closer to the Sun, and therefore incredibly hot and inhospitable. Although it has a thin atmosphere, Mars is the planet considered most similar to Earth, particularly in its rocky terrain, relatively small size and potential to sustain some form of life. Scientists believe Mars was even more like Earth early in its history.

Quick Comparison:

Stats Mars Earth
Place in the solar system 4th planet from sun 3rd planet from sun
Distance from the sun 227 940 000 km

1.52 (astronomical unit)

146 000 000

1 au

Size: diameter 6 779 km 12,745.591 km
(by volume)
95.3% carbon dioxide
2.7% nitrogen
1.6% argon
0.13% oxygen
traces of water vapour, neon, krypton and xenon
77 % nitrogen
21 % oxygen
1 % argon
0.038% carbon dioxide
traces of water vapor, neon, methane, krypton, hydrogen, nitrous oxide and ozone.
Surface air pressure Average of about 7 millibars 1013 millibars at sea-level
Surface gravity 3.71  metres squared 9.80 metres squared
Surface bulge Tharsis: a bulge 4000 km across and 10 km high Equatorial bulge: 43 km across the equator
Day length (sidereal day) 24 hours, 39 minutes and 35.25 seconds 23 hours, 56 minutes and 4 seconds
Year length 669.6 Martian solar days (about 1.9 Earth years) 365.2 mean solar days
Global average temp -55 degrees C
(-133 to 27 degrees)
14 degrees C
(-88 to 58 degrees)
Largest canyon Valles Marineris: 4000 km long, 5.3 km deep and 20 km wide Mariana Trench in the Pacific Ocean: 2550 km wide −10.9 km deep and 69 km wide
Escape velocity 5.03 km a second 11.19 km a second
Global magnetic field? No Yes
Moon(s) Two: Phobos and Deimos One: the moon