Ten Facts About Mars - Bob the Alien's Tour of the Solar System

The Valles Marineris, the greatest gorge on any planet in the Solar System, was caused when volcanoes erupting around it tore up the land, leaving a huge valley.

We can see how long Mars has been a 'dead' planet by the number of meteorite impacts on its surface. In comparison, Earth and Venus have fewer impact craters because they have newer surfaces formed by recent geological activity.

Mars has seasons like Earth. This is caused by the tilt of the planet's axis, at a similar angle to the tilt of Earth's axis.

The first space probe to take pictures of Mars' surface (Mariner 4 in 1964) is still in space, orbiting the Sun. Still orbiting Mars itself are Mariner 9 (launched in 1971), Viking 1 and 2 (launched in 1975), the Mars Global Surveyor (launched in 1996, which is currently looking for the Mars Polar Lander, launched in 1998) and the Mars Climate Orbitor (launched in 1998 to orbit Mars in 1999). These are American space probes. Russian probes orbiting Mars are Mars 2 and Mars 3 (launched in 1971), Mars 5 (launched in 1973) and Phobos 1 (launched in 1988). Japan has Nozomi orbiting Mars (launched in 1998).

Rocks from Mars have landed on Earth from meteorite impacts blasting debris through space.

Do you have any fascinating facts about Mars or any comments on any of the above facts? If so, email Bob at bob@bobthealien.co.uk!

NAME	Mars
MEANING OF NAME	Roman God of War (Ares is the Greek equivalent)
NAME IN FOREIGN LANGUAGES	Mars (French, German, Russian, Latin), Marte (Spanish, Italian, Portuguese), Ares (Greek)
AVERAGE DISTANCE FROM THE SUN	227,936,640 km / 141,633,260 miles / 1.52 A.U. Comparison with Earth: 149,597,890 km / 92,955,820 miles, 1.000 A.U.
CLOSEST DISTANCE TO THE SUN (PERIHELION)	206,600,000 km / 128,400,000 miles / 1.38 A.U. Comparison with Earth: 147,100,000 km / 91,400,000 miles, 0.983 A.U.
FARTHEST DISTANCE FROM THE SUN (APHELION)	249,200,000 km / 154,900,000 miles / 1.67 A.U. Comparison with Earth: 152,100,000 km / 94,500,000 miles, 1.017 A.U.
DIAMETER ACROSS EQUATOR	3,397 km / 2,111 miles Comparison with Earth: 12,756 km / 7,926 miles
DIAGRAM SHOWING PLANET'S SIZE COMPARED TO THE SIZE OF EARTH
CIRCUMFERENCE AROUND EQUATOR	21,344 km / 13,263 miles Comparison with Earth: 40,074 km / 24,901 miles
MASS	641,850,000,000,000,000,000,000 kg Comparison with Earth 5,973,700,000,000,000,000,000,000
TIME TO SPIN ON AXIS	24 hours, 37 minutes Comparison with Earth: 23 hours, 56 minutes
TIME TO ORBIT THE SUN (1 YEAR)	687 days Comparison with Earth: 365 days, 6 hours
DISTANCE PLANET TRAVELS TO COMPLETE ONE ORBIT	1,366,900,000 km / 849,400,000 miles Comparison with Earth: 924,375,700 km / 574,380,400 miles
GRAVITY (EARTH = 1)	0.38
ESCAPE VELOCITY	18,072 km/h / 11,229 mph Comparison with Earth: 40,248 km/h / 25,009 mph
MINIMUM SURFACE TEMPERATURE	-133 °c / -207°F / 140 K Comparison with Earth: -88 °c / -126 °F / 185 K
MAXIMUM SURFACE TEMPERATURE	27 °c / 80 °F / 300 K Comparison with Earth: 58 °c / 136 ° F / 331 K
WEATHER CONDITIONS	Mars is almost always sunny but very very cold. Dust in the thin atmosphere can cause haziness, and frost can form in polar regions. Thin water-ice clouds can form. Mars is extremely dry so there is never any rain on the planet (this may have been different in the past when surface water was present and the atmosphere was thicker). Mars has seasons, which means that the weather changes dependent on season - at the equator in summer, temperatures can reach up to 27 °c (80 °F). Mars is mostly calm although wind speeds can reach up to 100 mph and cause dust storms which can completely cover the planet.
CONTENTS OF ATMOSPHERE	95.3% carbon dioxide (CO₂), 2.7% nitrogen (N₂), 1.6% argon (Ar), and 0.1% oxygen (O₂). Other gases present in tiny quantities include carbon monoxide (CO), water (H₂O), nitric oxide (NO), neon (Ne), krypton (Kr), and xenon (Xe).
KNOWN MOONS	2 - Phobos and Deimos (both discovered in 1877 by Asaph Hall)
PAST MISSIONS (including nationality and year of launch - failed missions are in red)	Marsnik 1 (USSR, 1960), Marsnik 2 (USSR, 1960, Sputnik 22 (USSR 1962), Mars 1 (USSR 1962), Sputnik 24 (USSR, 1962), Mariner 3 (USA, 1964), Mariner 4 (USA, 1964), Zond 2 (USSR, 1964), Zond 3 (USSR, 1965), Mariner 6 (USA, 1969), Mariner 7 (USA, 1969), Mars 1969A (USSR, 1969), Mars 1969B (USSR, 1969), Mariner 8 (USA 1971), Cosmos 419 (USSR 1971), Mars 2 (USSR, 1971), Mars 3 (USSR, 1971), Mariner 9 (USA, 1971), Mars 4 (USSR, 1973), Mars 5 (USSR, 1973), Mars 6 (USSR, 1973), Mars 7 (USSR, 1973), Viking 1 (USA, 1975), Viking 2, (USA 1975), Phobos 1 (USSR, 1988), Phobos 2 (USSR, 1988), Mars Observer (USA, 1992), Mars Global Surveyor (USA, 1996), Mars Pathfinder (USA, 1996), Nozomi (Japan, 1998), Mars Climate Orbiter (USA, 1998), Mars Polar Lander (USA, 1999), Deep Space 2 (USA, 1999)
PRESENT MISSIONS	2001 Mars Odyssey (USA, 2001), Mars Express (Europe, 2003 - this mission included the failed Beagle lander), Spirit / MER-A (USA, 2003), Opportunity / MER-B (USA, 2003), Mars Reconnaisance Orbiter (USA, 2005), Phoenix / Mars Scout 1 (USA 2007)
PLANNED MISSIONS	Mars Science Laboratory (USA, 2009), Mars Orbiter (USA, 2011), Mars Sample Return Lander (USA, 2014), Mars Scout 2 (USA, 2011), ExoMars (Europe, 2013), Mars Astrobiological Field Lab Rover (USA, 2016), Mars Scout 3 (USA, 2018)
NOTABLE FEATURES	Olympus Mons, a volcano on Mars, is the largest volcano in the Solar System. The Valles Marineris is the greatest gorge in the Solar System.

MARS MENU	WELCOME TO MARS	IS THERE LIFE ON MARS?	MISSIONS TO MARS: PART ONE	MISSIONS TO MARS: PART TWO
MARS' MOONS	SUNSET ON MARS	BOB'S MARSCAM	FACTS ABOUT MARS	CHANGE DESTINATION

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