Author Archives: alistair

The Pale Blue Dot – our only home

I really love this quote about the Earth and how small and insignificant we really are.

It was written by the astronomer Carl Sagan and originally accompanied this picture of Earth (called Pale Blue Dot) taken from more than 6 billion kilometers away!

Pale Blue Dot“Look again at that dot. That’s here. That’s home. That’s us. On it everyone you love, everyone you know, everyone you ever heard of, every human being who ever was, lived out their lives. The aggregate of our joy and suffering, thousands of confident religions, ideologies, and economic doctrines, every hunter and forager, every hero and coward, every creator and destroyer of civilization, every king and peasant, every young couple in love, every mother and father, hopeful child, inventor and explorer, every teacher of morals, every corrupt politician, every “superstar,” every “supreme leader,” every saint and sinner in the history of our species lived there – on a mote of dust suspended in a sunbeam.

The Earth is a very small stage in a vast cosmic arena. Think of the rivers of blood spilled by all those generals and emperors so that, in glory and triumph, they could become the momentary masters of a fraction of a dot. Think of the endless cruelties visited by the inhabitants of one corner of this pixel on the scarcely distinguishable inhabitants of some other corner, how frequent their misunderstandings, how eager they are to kill one another, how fervent their hatreds.

Our posturings, our imagined self-importance, the delusion that we have some privileged position in the Universe, are challenged by this point of pale light. Our planet is a lonely speck in the great enveloping cosmic dark. In our obscurity, in all this vastness, there is no hint that help will come from elsewhere to save us from ourselves.

The Earth is the only world known so far to harbor life. There is nowhere else, at least in the near future, to which our species could migrate. Visit, yes. Settle, not yet. Like it or not, for the moment the Earth is where we make our stand.

It has been said that astronomy is a humbling and character-building experience. There is perhaps no better demonstration of the folly of human conceits than this distant image of our tiny world. To me, it underscores our responsibility to deal more kindly with one another, and to preserve and cherish the pale blue dot, the only home we’ve ever known.”

Zapping mosquitoes with lasers

Shooting down mosquitoes with lasersThe Economist has an article about anti-mosquito laser defense systems.

Seriously.

The first device described is called a photonic mosquito fence:

  • A series of posts about 100m apart
  • Each post has a cheap camera and light source and is connected to a central computer
  • When a camera detects movements it analyzes the source (mosquito species have distinctive wing-beat frequencies)
  • If the source is a mosquito the computer “trains a laser onto the insect and blasts it into oblivion”!

That is awesome! Apparently the system is also cheap enough to compete with current malaria protection.

The other system described uses a ‘curtain’ of infra-red light to which mosquitoes are highly sensitive. Also very cool.

Positive thinking works – but only if you believe it

I believe that a lot of life is a big confidence game.

From sport to public speaking, to work, to relationships I have found that self-belief goes a long way. I call it my confidence trick and it’s worked very well for me.

The Economist has an article outlining experimental results that suggest positive thinking can leave you worse off – if you don’t believe the positive thoughts.

Read the article for details of the experiment, but in short the results were:

  • High self-esteem => benefit from positive thoughts
  • Low self-esteem => worse off because of positive thoughts!

The article goes on to suggest that the positive thoughts clash with the self beliefs of those with low self-esteem thereby reinforcing those negative self-perceptions!

Positive thought - works if you believe itSo, positive thoughts do help – but only if you believe them.

Pott’s confidence trick has experimental support!

Incidentally, I think that this is the reason that religion is beneficial to many. Religion is a positive thoughts believability engine. The problem is that it so often gets co-opted into ignorant or political ends.

Keyboard shortcuts – the ALT trick

I just discovered a little time saving trick that I’m embarrassed to say I didn’t know before. When you spend as much time behind a computer as I do, little things like this are great.

In many screens you’ll encounter buttons with one letter underlined. For example the ‘A’ is underlined on the ‘Replace All’ button in the screen below.

alt-a

Instead of lifting my hand from the keyboard and clicking the button with the mouse, I can just hit ALT+A to press the button!

Similarly I could click the ‘Replace’ button with ALT+R or even untick the ‘In selection’ with ALT+I

Trust me, that makes a big difference.

News24 balls up their graphic design

My wife is a super graphic designer and I’ve learned a bit about the industry from her.

I can tell you for sure that she would DIE before publishing this image! It comes from the main page of a News24 website (otherwise quite a cool site).

plonker

I can’t believe that this got through to the public. Is it just me or does it look like Luke Watson has donated a lower leg to Natalie du Toit?

supersport-natalie

For those who don’t know, Natalie du Toit is one of South Africa’s greatest athletes. She lost her leg in an accident as a teenager but has gone on to be an amazingly successful Paralympic and Olympic athlete!

Defeating the News24 daily vote

Beating the News24 pollEvery day the News24 site has a user vote. I recently decided to take a closer look at their system – perhaps I could defeat the vote security. It would be fun (who says I’m a geek?) and I could learn something new.

I used a combination of Firebug and Python to watch their voting system in action. Pretty soon I realized that the security is very simple.

This is the process that News24 uses to record votes:
Flowchart showing how the News24 vote process works

  1. Show the user the vote (question and options) and get their choice
  2. Go to a page that checks if the user has already voted
  3. If the user has NOT voted yet:
    1. Save a file showing that the user has voted
    2. Move to another page that counts the vote
  4. Move on to the results page

It’s a pretty simple process and it works as long as nobody messes with it…

The problem is that it is very easy to derive the URL of the page that counts your vote (3b). So you can skip all the checks and go straight there as many times as you like!

So I wrote a very simple program (34 lines in Python including copious comments and whitespace) that:

  1. Fetches the vote details
  2. Asks which option to vote for and how many times
  3. Hits the vote counting page X times

As simple as that!

And no, I don’t use it. That would be pretty lame. The fun part was figuring it out and defeating a well known site. Not screwing up the polls for everyone.

Amazing photo of kingfisher diving

These are some stunning photos of a kingfisher feeding. At first I only saw the one below (best kingfisher photo I’ve ever seen) and couldn’t figure out how the photographer got it right.

Underwater shot of a Kingisher catching a fish

I managed to find the source page (check it out for high-res photos). It has some more stunning pictures which offer hints as to how the photographer could get the first shot.

Kingfisher diving towards a hole in the ice

Kingfisher emerging from a hole in the ice with a good catch

Superb visual illusions

I just came across an interesting website – Illusion of the Year Contest. They have a competition for best visual illusion of the year and some of the entries are great.

I’ve included some of my favorites below.

This one is very interesting. When you zoom out and the faces are smaller they appear to be looking at eachother. Zoom in and they suddently appear to be looking at you.

It seems like our brains use different heuristics to figure out where a person is looking. When no other information is available the brain uses darker patch in an eye to indicate where the iris is and hence where the person is looking.

When the images are closer and more information becomes available then the border of the iris itself dominates. Awesome illusion.

I really like this one. The two images are actually of exactly the same androgynous face. The only difference is the contrast. Higher contrast seems feminine while lower contrast seems masculine. I don’t really know why that would be the case – any ideas?

It does help to explain why woman wear contract increasing mascara, eye-liner, blush and lipstick.

Facial contrast suggests sex - visual illusion

Finally, this one is also pretty cool. The dots seem to be bouncing off of eachother. In fact the inner dot traces a square and the outer dot traces a circle. Maybe our brains have a hueristic to infer a relationship between them.

More 3D Street Art

I just came across the website of that guy who does the 3D street art. He’s got a few new pieces on there and it seems that he is tackling a whole new scale. This stuff is very clever and excellently executed.

This page that includes a few of the images (the official page is quite rubbish).

His name is Edgar Mueller and he’s from Germany. He’s been producing street art for decades. It seems there is a whole street painting community because he was awarded the maestro madonnari’ (master street painter) at the world’s largest street painting festival.

More amazing 3D street art from Edgar Mueller

More amazing 3D street art from Edgar Mueller

More amazing 3D street art from Edgar Mueller

National Geographic’s Infinite Photo

National Geographic have put together this cool “infinite photograph”. They’ve used hundreds of user submitted photos to create an infinitely zoomable photo mosaic.

To see what I mean let’s go through an example. You start off with this image. Use the yellow border to choose an area to zoom into:

Example from National Geographic's Infinite Photo

The app will zoom in to show the selected area made up of hundreds of small photos:

Example from National Geographic's Infinite Photo

You can carry on zooming in forever. Eventually you’ll zoom in to a single image and the whole process starts again – hence the infinite…

Example from National Geographic's Infinite Photo