Out here in Spain we’re usually blessed with clear night
skies so we can view the stars and planets without too much light pollution.
There’s something about stargazing that tugs the imagination, a sense of
wonder, perhaps.
Nasa just released a video revealing what Mars may have looked like as a young planet billions of years ago. http://news.sky.com/story/1168023/nasa-video-mars-evolution-from-watery-world
It appears to have had a thick atmosphere that was warm enough to support oceans of liquid water - a crucial ingredient for life.
The animation, created by Nasa's Conceptual Image Lab, shows how the surface of Mars might have developed over four billion years. The artist's concept is based on evidence that Mars was once very different. It shows vast Martian lakes surrounded by mountain ranges, beneath Earth-like blue skies and rapidly moving clouds.
The shift from a warm and wet climate to a cold and dry one is shown as the animation progresses. The lakes dry up and transform into a rocky landscape with canyons, volcanoes and craters. The atmosphere gradually turns to the dusty pink and tan hues seen on Mars today.
Nasa scientist Dr Pan Conrad told Sky News: "We think that the when Mars was created it was a lot wetter and warmer than it is today. It probably lost much of its atmosphere over time and that's how it came to be such a desert and cold place."
Red dust - from the iron in its soil - now covers almost all the surface of the Red Planet, which has an average temperature of -27C (-80F).
Nasa's Curiosity rover has been exploring the surface of the planet since August 2011 and has made several discoveries to support the theory that Mars was once able to support life. These include pebbles providing evidence that a stream once flowed on the planet, and more recently, Martian dust, dirt and soil suggesting a "substantial" amount of water on Mars.
The planet’s atmosphere is over ninety-five percent carbon
dioxide and its rocks, soil and sky have a red or pink hue. The distinct red
colour was observed by stargazers throughout history and the planet was named
by the Romans in honour of their god of war. Other civilizations had similar
names, for instance the ancient Egyptians called the planet the red one.
It has two orbiting moons, Phobos and Deimos.
Galileo was the first to observe Mars through a telescope
and eighteenth century Frenchman Giovanni Cassini first noted the planet’s
poles.
However, in 1892 it was Schiaparelli who was responsible for
many of the popular illusions about the planet.
When he saw grooves or channels on the surface of Mars, his report in
Italian used the word canali to
describe the phenomenon. Translations interpreted canali as canals rather than channels and the description evoked an
image of an old and sophisticated but slowly dying civilisation on our sister
planet.
Three years later American astronomer Percival Lowell published a non-fiction book, Mars, in which he speculated about the terrain and the presence of life on the planet.
These works were read by Wells and fired his imagination in
the writing of his classic The War of the
Worlds which was given the Spielberg blockbuster treatment, inevitably transposing
the story to the United States. A
British version came out at the same time (2005), H.G. Wells’s War of the Worlds.
Lowell published two more books, Mars and its Canals (1906) and Mars
As the Abode of Life (1908).
Fourteen years after Lowell’s death, Pluto was discovered – its presence
beyond Neptune had been predicted by Lowell. He’s probably turning in his grave
now that Pluto has been demoted from planet to dwarf planet (plutoid).
Then in 1911 the serial ‘Under the moons of Mars’ was
published in the monthly All Story
magazine. Written by the creator of
Tarzan, Edgar Rice Burroughs, the story was a great hit and was later published
in book form as A Princess of Mars. This was the first of eleven swashbuckling
imaginative books Burroughs set on Mars – or, as the inhabitants called it,
Barsoom. The first three volumes in the series actually constitute a single
super epic. A film version, John Carter
was released in 2012 to a mixed reception; the fans loved it, most
of the critics panned it, and the marketing was abysmal.
Many later
science fiction works, from the Flash Gordon and Buck Rogers films of the 1930s,
to Ray Bradbury's The Martian Chronicles, to the Star Wars films,
to Kim Stanley Robinson’s Mars Trilogy, about terra-forming the red planet,
also offer nods in Burroughs’s direction. Robert A Heinlein’s novel The
Number of the Beast and Alan Moore’s graphic novels of The League of
Extraordinary Gentlemen directly reference Barsoom.
This article’s
title is taken from the classic short story by StanleyWeinbaum published in
1934.
In June 2003 – when the positions of Mars and Earth provided
for the shortest possible route, a condition that prevails every twenty-six
months - the Mars Express rocket was launched from the Baikonur cosmodrome in
Kazakhstan by the European Space Agency. Comprising an orbiter and its lander,
Beagle 2, its journey took six months at a velocity of 10,800km an hour. The spacecraft arrived in orbit around Mars
on Christmas Day, 2003. Pictures and information are still being collected by
the orbiter. The lander failed to respond to Earth-based instructions so was
deemed a failure. It’s unlikely that it was tampered with by any Martians,
however... Indeed, Mars Express, so called because of the rapid and
streamlined development time, represents the European Space Agency’s first
visit to another planet in the Solar System. The spacecraft borrows technology
from the failed Mars 96 mission and from ESA’s Rosetta mission that is
currently en route to comet 67P/Churyumov-Gerasimenko. The mission helps to
answer fundamental questions about the geology, atmosphere, surface environment,
history of water and potential for life on Mars. For the past decade, ESA’s
Mars Express orbiter has been observing atmospheric structure on the Red
Planet. Among its discoveries is the presence of three separate ozone layers,
each with its own characteristics. A new comparison of spacecraft data with computer
models explains how global atmospheric circulation creates a layer of ozone
above the planet's southern winter pole. The full article can be found at http://sci.esa.int/mars-express/52881-a-seasonal-ozone-layer-over-the-martian-south-pole/
Probes sent from Earth beginning in the late 20th century have yielded a dramatic increase in knowledge about the Martian system, focused primarily on understanding its geology and possible habitability potential.
Engineering interplanetary journeys is very complicated, so the exploration of Mars has experienced a high failure rate, especially in earlier attempts. Roughly two-thirds of all spacecraft destined for Mars failed before completing their missions, and there are some that failed before their observations could begin. However, missions have also met with unexpected levels of success, such as the twin Mars Exploration Rovers operating for years beyond their original mission specifications.
Since 6 August 2012, there have been two scientific rovers on the surface of Mars beaming signals back to Earth (Opportunity, and Curiosity of the Mars Science Laboratory mission), and three orbiters currently surveying the planet: Mars Odyssey, Mars Express, and Mars Reconnaissance Orbiter.
To date, no sample return missions have been attempted for Mars, and one attempted return mission for Mars' moon Phobos (Fobos-Grunt) has failed. (previous 4 paragraphs, from Wikipedia).
On 18 November (Monday!), the Mars Atmosphere and Volatile
Evolution Mission (MAVEN), is set to launch. It will explore the planet’s upper
atmosphere, ionosphere and interactions with the sun and solar wind. Scientists
will use MAVEN data to determine the role that loss of volatile compounds, such
as CO2, N2, and H2O, from the Mars atmosphere
to space has played over time, giving insight into the history of Mars
atmosphere and climate, liquid water, and planetary habitability. On 8 November
Maven was placed on top of the Atlas V rocket; checks so far look good for
launch. See http://lasp.colorado.edu/home/maven/
The magic of Mars still exerts its influence and pulls us
there…
