MARS
 

By Lydia Kirwan and Sarah Mason.

Glenlola Collegiate School

Bangor, Northern Ireland

 
 

Mars – The History

The first people to catch sight of Mars just saw it as a red blob followed by a strange loop in the sky.

The first reported sighting of Mars that we know of is the Babylonians - around 400BC. The Egyptians and Greeks and Romans all saw it and had their own explanations for it.

The Babylonians made careful observations of their calendar and how the sightings of Mars linked into it. They had many religious reasons for it, but never tried to explain these phenomena’s that they witnessed. They called Mars Nergal – The Great Hero, the King of Conflicts.

The Egyptians were the first to notice that the stars seem "fixed" and that the sun moves in relation to the stars. They also noticed five bight objects in the sky (Mercury, Mars, Venus, Jupiter, and Saturn) that seemed to move in a similar way. They called Mars Har Decher - the Red One.

The Greeks and Romans Greeks called the planet Ares after their god of war, while the Romans called it Mars. Its sign is thought to be the shield and sword of Mars.                   

Most of the early people thought Mars to be a sign or war or  the God of War. They thought these things probably because of the violent,  fiery red colour of the planet, which actually is a dust which covers the surface.

Characteristics of Mars

The average distance that Mars is from the sun is 227.94 million km (141.64 million miles). At the Equator its’ diameter is 6,786km (4,217 miles). The Earth’s mass = 1 - Mars = 0.11

The Martian day, i.e. time taken for it to rotate on axis, is 24.62 hours, nearly an hour longer than an Earth day. Its’ year, i.e. time taken to orbit the sun, is nearly double an Earth year – 686.98 Earth days.

The average temperature is rarely over freezing, one of the main reasons why it would be extremely hard to survive on Mars.  The surface temperature -120 ° C to 25 ° C.

It has two moon which are called  Phobos and Deimos , they are named after the two dogs that the Roman God Mars owned. These ‘moons’ are dark chunks of rock, or, they may be asteroids captured by the gravitational force of Mars. They each orbit Mars nearly twice in one day.

WHAT HAVE SCIENTISTS FOUND OUT ABOUT MARS?

Space probes over the years

One of the first probes to land on Mars was NASA’s two Viking probes.  They were launched in 1975 and landed on Mars in 1976.  They consisted of a lander, obiter and land support structure.  They looked specifically for evidence of past or present life.

Before it was lost Russian Phobos 2 imaged Phobos, Mars’ tiny innermost moon, as did NASA’s Mars Global Surveyor, which is still operating.  NASA;s Mars Odyssey is to date also still on Mars.  It has been providing evidence, being interpreted both for and against there being water-providing life on Mars.

Mars Global Surveyor in orbit around Mars (NASA image)

 

Future Missions

On May or June 2003, Mars Express and its lander Beagle 2 will blast off into space starting its six month journey to Mars.  It will be the first ever European spacecraft to head for Mars.  It will probe more deeply into the water debate and should also provide the first global map of Phobos.  It will also address other unknowns, such as the difference between the young, northern lowlands and the rugged, southern highlands and the atmosphere and climate on Mars.

Other new spacecraft hoping to land on Mars in 2003/4 are NASA’s two rovers, which will arrive shortly after Mars Express and the Japanese ISAS’s spacecraft Nozomi.

All of the aims and results of all the missions around Mars is undertaken by the International Mars Exploration Working Group.


Comparing Mars to Earth

Similarities

Both are rocky planets. 

Both tiled on a rotational axis, therefore both have seasons.

Differences

MARS

EARTH

228 (millions of km) from sun

160 (millions of km) from sun

Diameter = 12,756km

Diameter = 7,786km

A year on Mars = 1.881 earth years

A year on earth = 1 year

360º rotation takes 1:00:38

360º rotation takes 0:23:56

Too cold for water

Water covers more than 2/3 of the earth

Mars – Class Practical work

We have seen during our research that Mars once had a lot of volcanic activity.  The evidence for this is the many volcanoes we can observe today on Mars, including Olympus Mons, the highest volcano in the solar system.

On Earth, there are different shapes of volcano and these can be classified depending on how they were formed:

o        Shield volcanoes – gentle eruption, convection currents in matle form ‘hot spots’

o        Cone volcanoes – violent eruption, caused by tectonic activity.

 

How can we work out the volcano type?

It can be determined from the following formula:

SHAPE FACTOR =  diameter of volcano

                                                        height of volcano

                            

If the value for the shape factor (SF) is less than 10, then it is a cone volcano, but

if the value is greater than 10, then it is a shield volcano.

                             SF < 10  à CONE

                             SF > 10 à SHIELD

Our practical task is for students to work out the type of volcanoes present on Mars, and then to make conclusions as to how they were formed.

 

The table shows values for the diameter and heights of some volcanoes on Mars.  Pupils have to work out the shape factor and then determine the volcano type. [NOTE:  all the volcanoes on Mars are SHIELD volcanoes.  This indicates that there is probably no tectonic activity on the planet.)

VOLCANO

DIAMETER (km)

HEIGHT (km)

SHAPE FACTOR

Hecate Tholus

     170

        6

 

Olympus Mons

     520

       23

 

Ascraetus Mons

     400

       17

 

Uranius Tholus

       83

        3.5

 

Ulysses Tholus

        91

        4

 

Elysium Mons

      170

        9

 

Our Final thoughts on Mars .

          We thoroughly enjoyed our research on Mars - the Red Planet. We never knew very much about this planet but now at the end of our research we have all the knowledge about it that we could wish for.

          We think it was very worthwhile investigating the subject we chose. We now have the answers to the questions that we asked ourselves at the beginning. Why is Mars red?? Is there life on Mars, really?? How different is it to Earth?

           The future for Mars is promising; Mars express will soon be going to Mars to gather more information for us. So our knowledge of the planet can improve and grow and even the unanswered questions maybe answered.

          If it is possible one day to travel to Mars; safely, we would be extremely eager to travel there and see the planet itself and all its marvels.                                

   mars

CITATIONS

Books : Exploring The Planets by Brain Jones

Astronomy Now magazine

Computer : www.nasa.com/mars

Dorling Kindersley encyclopaedia