Transcript MARS

MARS
SPACE
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DEFINITION
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The fourth planet from the Sun, just past the Earth. Often called the 'Red Planet', due to its vivid colour.
REASONS TO VISIT
See the longest ever canyon system, stretching over 5,000km (3,100 miles)
Visit the Solar System's largest volcano - over 50 times bigger than those on Earth
Decide for yourself whether the Red Planet once contained life
NUMBER OF MOONS · 2
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Solar System Jigsaw Can you
build the Solar System?
WHAT TO SEE
Mars has some of the most spectacular scenery in the Solar System.
Valles Marineres
A giant canyon system stretching over 5,000km (3,100 miles) along the equator with an average depth of 6km. See if you can spot the erosion channels that
could reveal the planet's watery past.Olympus Mons
The largest volcano in the Solar System. Reaching 27km (17 miles) high and 700km (435 miles) across. But don't be afraid - this monstrous volcano is now
extinct, so your visit will be a safe one.The face
In 1976, Viking Orbiter 1 sent pictures of a very unusual rock formation. When the Sun strikes Mars at a certain angle, the shadow looks like a human face.Is
this proof of alien intelligence at work? Or is it just chance that the rugged surface of Mars conjures up this image? Until there is more evidence, you will have
to decide for yourself.LOCAL HISTORY
It's usually claimed that Mars was named after the Roman god of war because of its angry red colour. But early on in the Roman empire, Mars was worshipped as a god
of growth and fertility.
SPOTTING MARS FROM THE EARTH
Mars' red colour, though more pronounced when seen through a telescope, is still noticeable with the naked eye.
Mars can often be spotted from Earth. Usually it travels across the sky from east to west. However, for 70 days of its two year orbit, it reverses direction
across the sky. This is the best times to observes Mars, because it's at the closest point to Earth. Find out if you can see Mars in the sky this month
TRAVEL INFORMATION
Journey time · 5.25 Earth months
1 Martian year · 2.11 Earth years
Contacting home · Time lag = 25.4 minutes
Before you leave
Mars is closer in temperature to Earth than any of the other planet in the Solar System. But don't let this catch you off your guard. Mars' weather is even more
unpredictable than our own.
We recommend a summer visit, when the temperature can reach a pleasant 27ºC. But keep an eye on the weather forecast! Storms can sweep across the
whole planet. Within days, the temperature can plummet by 20 degrees.
Travellers in the winter months should note that Mars can reach a bitter -87ºC.
One final word of warning - make sure you are prepared for dust storms. Tornadoes as large as eight kilometers high have been seen causing havoc across
the Martian landscape.
When you arrive
Your first decision when you arrive will be which hemisphere to head for. The southern hemisphere is higher, and has a more rugged landscape.
The northern hemisphere lies an average of five kilometres lower. We know that the surface there is younger as there are fewer impact craters.
There is no evidence of plate tectonics on Mars. This means that growing volcanoes aren't disrupted by surface movements. So they can grow 100 times
larger than on Earth, like Olympus Mons. But unlike Olympus Mons, other volcanoes are still active, so watch where you park!More from BBC
BBC Space - Life on Mars?
Explore the Red Planet for signs of life
WEATHER ON MARS
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it is the other neighbour to Earth (Venus being the other). It has a radius at its equator of about
2110 miles and is around 141,634,937 miles from the Sun.
Mars' atmosphere is very different to ours, and weighs less than 1 percent of Earth's, as it is made
up principally of carbon dioxide with small amounts of other gases, including neon, water,
nitrogen, argon and oxygen.
The water on Mars is not very plentiful, but it can still form clouds when it reaches certain heights.
Explorations of Mars have also seen evidence of fog, frosts and snow. The snow appears to fall in
the polar caps during winter.
Temperatures on Mars are quite a bit colder than here on Earth, with an average ranging from 140C to 20C. It is therefore cooler than Earth, even though the carbon dioxide in its atmosphere
creates a greenhouse like effect. This CO2 though is so thin its influence is minimal.
Mars rotates on its axis with a similar tilt to that of Earth (about 25 degrees) and therefore has
seasons like we have - summer, winter, spring and autumn. Like our planet, these seasons are
opposite depending on whether you are in the north or southern hemispheres. Mars' rotation
around the Sun takes about twice as long as ours and therefore the length of a season is about
double the length of ours.
The orbit of Mars is a lot more oval than Earth's which means it varies in distance from the Sun,
varying from 128 million miles to 154 million miles. This also has an effect on the length of its
seasons. At the moment Mars is nearest to the Sun when the southern hemisphere is
experiencing summer, which means they are currently shorter but warmer than those which are in
the northern hemisphere.
Mars usually appears quite cloudless, however there are occasionally c
THE RED PLANET
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Programme One: Approaching Mars
Presented by Heather Couper
On 27 August, Mars will make a close approach to Earth, coming nearer to us than it has done for 59, 619 years. Across the globe, thousands of people will be looking out
for it – just as they have done for centuries. In this programme, Heather Couper uncovers the history of mankind’s ongoing fascination with the planet Mars, and the
incredible metamorphoses our beliefs about the red planet have gone through.
For ancient civilisations – the Egyptians, the Romans – this fiery red star was believed to be the home of a great god. Following the invention of the telescope,
astronomers peered into the night sky and saw Mars as an Earth-like world, lush and full of life. In the nineteenth century, eccentric US businessman Percival Lowell
became convinced Mars’ surface was criss-crossed by canals, the handiwork of a sophisticated civilisation desperately trying to channel water to the cities of their dying
world. Lowell’s picture of Mars influenced many, including HG Wells – who in turn, through War of the Worlds, created an image of Mars as a place of threat which to this
day remains part of our collective culture.
And working today is a generation of scientists determined to see a manned mission to Mars within their lifetimes. One of them is British Antarctic Survey microbiologist
Charles Cockell, whose passion for Martian exploration even led him into a brief career in politics. In 1992, he stood against John Major in the general election, as the sole
candidate for the Forward to Mars party – the first political party in history to represent the interests of another planet.
But in spite of the lobbying, we’re not there yet. The reason: Mars is inhospitable and very hard to get to! Heather hears about the challenges we face before we can see
humans land on Mars, and wonders what – having made the arduous nine month, four hundred million mile journey - it might be like to take the first footsteps on the red
planet.
Listen again to Programme 1
Programme Two: Fourth Rock from the Sun
Presented by Heather Couper
Heather Couper charts the ups and downs of the scientific exploration of Mars, since the launch of the first NASA probe in 1965. Mars was still an unknown world, and
there were hopes that on its surface there would be vegetation, or mosses and lichens at the very least. There were even a few people clinging onto nineteenth century
stories of canals on Mars. But the photographs Mariner 4 sent back to Earth didn’t show canals, trees, or even moss. They showed a dry, dusty, crater-pocked desert,
totally devoid of life. Our neighbouring planet had proved to be disappointingly inhospitable.
In spite of the letdown, more probes were sent, and as the technology and cameras got better, Mars regained some of its intrigue. There were signs of riverbeds, now
dried up – but perhaps they once contained water. And where there’s water, there’s the possibility of life, particularly microscopic life-forms. In 1976, NASA sent the Viking
lander to Mars carrying on board a series of experiments to test for life. Although the official line is that none was found, one of the lead scientists on the mission, Gil
Levin, is, twenty five years on, still insistent that his experiment did find evidence of microbial life on Mars.
And today, the intrigue continues. More signs of water have been discovered – frozen in polar icecaps, the dried out lakebeds, and, tantalisingly, the marks of gullies
formed in the last few billion years – recent enough for geologists to wonder whether there might still be liquid water on the planet. And so right now, there are no fewer
than four unmanned missions heading to Mars, including the British Beagle 2 lander. Heather ponders our chances of finding microbes on Mars, and wonders what the
impact would be if we really were to discover life on another world – to learn that we are not alone.
Listen again to Programme 2
Programme Three: Everyday Life on Mars
Presented by Sue Armstrong
There are landscapes on Earth – the bleak high Arctic, the dusty deserts of Utah – where, if you let your imagination take a little leap, you could believe you were on Mars.
And there are places where space scientists have done just that – donning space suits, testing remote-controlled robots, and living in a cylindrical, 8 metre wide, tin
habitation module. Their aim is to find out what it would be like to live on Mars, and what sort of equipment, life support systems and living space would be needed to keep
humans alive, sane, and able to do exploratory science for the three years a manned mission to Mars would take.
Sue Armstrong learns the stories of the people behind these Mars simulations, such as NASA scientist Dr Nigel Packham, one of a team of four who spent 91 days in a
chamber testing out systems for recycling air, water and waste products. The crew became very close during their three month enclosure, and Nigel found that the hardest
part of the whole experience was leaving the chamber at the end. Charles Cockell talks about what it’s like to have to wear a heavy mock space-suit made of tent canvas,