Tag Archives: brief

A brief history of Martian exploration – as the InSight Lander prepares to launch



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An artist’s rendition of the InSight lander – which will collect data on what’s inside the planet Mars.
NASA

Helen Maynard-Casely, Australian Nuclear Science and Technology Organisation

Roughly every two years Mars and Earth wander a bit closer to each other, making the leap between these two planets a little easier. In July this year, Mars will only be about 58 million kilometres away – and NASA is set to take advantage by launching their next mission to the red planet in May 2018. The InSight Lander, will be the first Mars mission to investigate the planet’s “inner space”, and will listen for marsquakes to investigate the crust, mantle, and core.

InSight will join two rovers currently exploring the surface of Mars, and 14 spacecraft that are in orbit about it – albeit only six of which are currently sending us data.




Read more:
Ice mined on Mars could provide water for humans exploring space


Why does Mars, the red planet, have such a hold over us?

There are, after all, seven (or eight) other planets to explore – and yet we seem to have such a hang up on this one.

I guess it’s the tantalising nature of Mars. Here is a planet that we could conceivably walk on (unlike the gas giants), without being crushed by atmospheric pressure (like on Venus), having to deal with the radiation of being closer to the sun (Mercury) or just being far too far away (like Pluto). It calls to us through science fiction and fact, a planet that is so like our own Earth, but so unlike it at the same time.

Mars fly-over movie, made by visual artist Seán Doran, via NASA/JPL/University of Arizona.

The six current operational missions show that the fascination with Mars isn’t limited to one country, as European, Russian, American and Indian space agencies all have stakes in these crafts.

For comparison: our other nearest neighbour, Venus, only has one spacecraft currently in orbit about it, Akatsuki the spacecraft that wouldn’t quit. In fact, after the dramatic ending of the Cassini spacecraft, the only other planet currently being orbited by an Earth-built satellite is Jupiter, with the Juno mission.




Read more:
Juno mission unveils Jupiter’s complex interior, weather and magnetism


Water on Mars

But, while our progress to walking on Mars has been very slow, our progress in understanding our neighbour has been really quite impressive. When I started my planetary science degree in 2001, the course did not include sedimentology, the branch of geology that investigates how water has shaped rocks. It was deemed there was no point as no water has been seen on any other planet.

By the time I was in third year, the first years students behind me were getting well versed in how water could push around sand, silt and clay on other planets.

Finding water on Mars had been an obsession to many, and thanks to data from Mars rovers Spirit, Opportunity and latterly Curiosity we know that it’s there – just trapped in the rocks. A couple of years ago it was thought that we had even found water flowing on the surface of Mars, but that evidence is (ahem) drying up now.




Read more:
Dear diary: another day in the life on Mars


However, whether the water flows or is trapped in the rocks, the next question is where is the rest of it? If many of the rocks we see on Mars had been laid down by water – where is that water now?

The answer would be tangled up with the fate of Mars’s atmosphere. Though pitifully thin now, it must have been thick enough in the past to support flowing water on the surface. The mission of the spacecraft Maven (along with others) has been investigating this question – and all evidence is pointing to the Sun as the culprit for Mars’ missing atmosphere, with the solar wind gradually stripping it away.

Mars’ surface

It’s often touted that we know more about the surface of Mars than we do the bottom of our own oceans – and in terms of mapping resolution that’s true. Through the efforts of four orbiting missions we know how old most of the surface is, as well as how active it has been.

You can spend a joyful afternoon of procrastination flitting through HiRISE images that show sweeping dunes and pock-marked plains on Mars. With these images we can really apply our understanding of processes on Earth to what makes up the surface of Mars – from the formations of geological features, the movement of dust and sand and how the ice caps change through the seasons.

What’s inside Mars?

So we know there is water on Mars, we know where its atmosphere went and also the shifts of its sands – but there’s a missing piece of the puzzle. What’s on the inside?

To be fair, in this respect the interior of our own Earth is just as much of a mystery – but we have had centuries of seismic studies. From monitoring the passage of earthquakes through our planet we have built a picture of the layers that make up its interior. From that we’ve been able to undertake experiments that recreate the conditions and add more to that picture. At the moment we can only guess at the conditions within the interior of Mars – something that the InSight mission will answer.




Read more:
Before we colonise Mars, let’s look to our problems on Earth


After this, the next hurdle will be getting something back from Mars. We have a handful of meteorites that we know came from Mars, but having a sample that’s been collected and returned from a known location will priceless. NASA’s next rover, Mars 2020, will plan to do just this – but the return to Earth bit is still to be worked out.

The ConversationFrom sample return to human exploration is still a massive step, and will require a number of innovations to get there. But with the knowledge we’ve built from the missions over the last decade, it’s becoming more of a reality.

Helen Maynard-Casely, Instrument Scientist, Australian Nuclear Science and Technology Organisation

This article was originally published on The Conversation. Read the original article.

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From shouting it out to staying at home: a brief history of British voting


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Hogarth’s The Polling, from the Humours of an Election series.
Wikipedia

Malcolm Crook, Keele University and Tom Crook, Oxford Brookes University

Most of the voters who will be casting their ballots in the general election on Thursday June 8 will take their right to do so for granted, unaware of the contested history of this now familiar action. It’s actually less than 100 years since all adult males in the UK were awarded the franchise for parliamentary elections, in 1918, in the wake of World War I. That right wasn’t extended to all adult women for a further ten years after that.

Even today, it might be argued, the democratic principle of “one person, one vote” has not been fully implemented, since the royal family and members of the House of Lords are not allowed to vote in parliamentary elections. And even after the mass enfranchisement of the early 20th century, university graduates and owners of businesses retained a double vote, the former in their university constituencies as well as where they lived. These privileges were only abolished in 1948, in face of overwhelming Conservative opposition.

How Britain votes today is also a relatively late development in electoral history. Until 1872, parliamentary electors cast their votes orally, sometimes in front of a crowd, and these choices were then published in a poll book. Public voting was often a festive, even riotous affair. Problems of intimidation were widespread, and sanctions might be applied by landlords and employers if voters failed to follow their wishes, though this was widely accepted at the time as the “natural” state of affairs.

Open voting even had its defenders, notably the political radical John Stuart Mill, who regarded it as a manly mark of independence.

But as the franchise was partially extended in the 19th century, the campaign for secrecy grew. The method that was eventually adopted was borrowed from Australia, where the use of polling booths and uniform ballot papers marked with an “X” was pioneered in the 1850s.

More recent reforms took place in 1969, when the voting age was lowered from 21 to 18. Party emblems were also allowed on the ballot paper for the first time that year. It’s this kind of paper that will be used on June 8.

Staying at home

What no one predicted, however, when these franchise and balloting reforms were first implemented, is that voters would simply not bother to turn out and that they would abstain in such considerable numbers.

To be sure, this is a relatively recent phenomenon. In fact, turnout for much of the 20th century at general elections remained high, even by European standards. The best turnout was secured in the 1950 general election, when some 84% of those eligible to do so voted. And the figure didn’t dip below 70% until 2001, when only 59% voted. Since then things have improved slightly. In 2010, turnout was 65%. In 2015, it was 66%. But the fact remains that, today, a massive one-third of those eligible to vote fail to do so, preferring instead to stay at home (and the situation in local elections is far worse).

Turnout over the years.
Author provided

What was a regular habit for a substantial majority of the electorate has now become a more intermittent practice. Among the young and marginalised, non-voting has become widely entrenched. Greater personal mobility and the decline of social solidarity has made the decision to vote a more individual choice, which may or may not be exercised according to specific circumstances, whereas in the past it was more of a duty to be fulfilled.

Voters rarely spoil their papers in the UK, whereas in France it is a traditional form of protest that has reached epidemic proportions: some 4m ballot papers were deliberately invalidated in the second round of the recent presidential election. Like the rise in abstention in both countries, it surely reflects disenchantment with the electoral process as well as disappointment with the political elite.

In these circumstances, the idea of compulsory voting has re-emerged, though in liberal Britain the idea of forcing people to the polling station has never exerted the same attraction as on the continent. The obligation to vote is a blunt instrument for tackling a complex political and social problem. When the interest of the electorate is fully engaged, as in the recent Scottish or EU referendums, then turnout can still reach the 75% to 80% mark.

The ConversationHowever, in the forthcoming parliamentary election, following hard on the heels of its predecessor in 2015, the EU vote and elections to regional assemblies in 2016, plus the local elections in May, voter fatigue may take a toll. It’s hard to envisage more than two-thirds of those entitled to do so casting their ballot on June 8. Given the relatively small cost involved in conducting this civic act, which is the product of so much historical endeavour, such disaffection must be a cause for significant concern.

Malcolm Crook, Emeritus Professor of French History, Keele University and Tom Crook, Senior Lecturer in Modern British History, Oxford Brookes University

This article was originally published on The Conversation. Read the original article.


Brief History of Cartoons



Article: A Brief History of Dude


The link below is to a brief history of the word ‘dude’ and its use in popular culture.

For more visit:
http://www.theatlantic.com/magazine/archive/2013/11/dude-transcends/309528/


Article: Brief history of Alcohol Consumption in Australia


The link below is to an article that takes a brief look at the history of alcohol consumption in Australia.

For more visit:
http://www.lifehacker.com.au/2013/03/a-brief-history-of-alcohol-consumption-in-australia/


Article: Brief Histories of Items for Babies


The link below is to an article that takes a quick look at various items useful for babies.

For more visit:
http://mentalfloss.com/article/49280/brief-history-7-baby-basics


Article: A Brief History of Text Messaging


The link below is to an article with a brief history of Text Messaging.

For more visit:
http://mashable.com/2012/09/21/text-messaging-history/


Article: Brief History of Breast Implants


The link below is to an article that takes a brief look at the history of breast implants.

For more visit:
http://www.mentalfloss.com/blogs/archives/20727


Article: A Brief History of “American Cheese”


The link below is to an article offering a brief history of American Cheese.

For more visit:
http://www.mentalfloss.com/blogs/archives/21497


Article: A Brief History Of Computers That Changed The World


The link below is to an article that considers computers that have changed the world.

For more visit:
http://www.makeuseof.com/tag/a-brief-history-of-computers-that-changed-the-world/


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