Posted by: Corina Paraschiv | July 4, 2010

The scoop behind Hubble’s Deep Sky picture

You must have seen this picture before.

This is the Hubble Ultra Deep Space picture

This is the Hubble Ultra Deep Space picture

This picture was taken with the Hubble and it’s called the Hubble Ultra Deep Space picture.  What I knew from a visit to the Griffith Observatory a couple years back was that this picture represents what happens when you hold a needle at an arm’s length towards the sky — the round tip of it would represent approximately the area of space that this picture covers — an impressive thought!

But here’s the whole story behind the picture.  Now the first thing you might remember was that this picture was taken by the Hubble telescope, and that telescope seems to be a miracle in itself.

When Galileo first discovered the telescope, that instrument was barely two pieces of glass put together.  When I say discover, I do mean discover, not invent – because the telescope per se was actually first introduced in Northen Europe for naval wars on ships.  It quickly spread throughout the continent, from France to Italy, where Galileo Galile finally set his hand on it, and saw all the potential it could yield for astronomy.

Since then, humans struggled to make telescopes that could be increasingly more clear.  You see, the images you used to get were very blurry, because the focal point for the different colors that were caught by the telescope varied from color to color.  The effect was all the more accentuated as the telescope was short.  So people started building ridiculeously long telescopes, measuring sometimes up to 45 meters, in order to get crisp pictures.  But those telescopes were very approximate, and could be swung and lose their positions with the smallest gust of wind.

One of the early (45 meters long) telescopes

One of the early (45 meters long) telescopes

That is, until someone had the brilliant idea to create a telescope using two mirrors which would focalize the image without needing this much length.  Many subsequent changes happen to make the process better.  But all of them had the similar concept of the mirrors reflecting the ligth and directing it into an eye piece.

This is how the upside-down images were generated through the mirror telescopes

This is how the upside-down images were generated through the mirror telescopes

At that time, I think it must have been around the 1970s, astrophotogrpahy is born.  Daguerre’s process to take a still picture of a life scene (which took hours of exposure — you can see the first picture ever taken and read about it in the previous article I wrote on photography), is suddenly recognized as being a perfect tool for astronomy, where long exposures are actually needed.

Henry Draper, the amateur astronomer who took the first deep sky picture in history

Henry Draper, the amateur astronomer who took the first deep sky picture in history

A 51 minute exposure of the Orion Nebula was taken in September 1880 by Henry Draper (at right; 1837-1882), a doctor and prominent amateur scientist (and the son of John William Draper), and two years later he took another lasting 137 minutes which revealed the entire nebula and the faintest stars in it.

A 51 minute exposure of the Orion Nebula was taken in September 1880 by Henry Draper (at right; 1837-1882), a doctor and prominent amateur scientist (and the son of John William Draper), and two years later he took another lasting 137 minutes which revealed the entire nebula and the faintest stars in it.

Now all this you may or may not have known but what I’m about to tell you is really marvelous and knowing the previous things helps us realize just what a little miracle the Hubble telescope is in the history of astronomy.

Following these first pictures like the one you saw before, the telescopes became bigger and bigger, the pictures became more and more sophisticated with colors, and the places humans were physically capable of putting all those installations in became higher and higher in desert mountains.  The air in those places is very dry and the altitude, sometimes even higher than the clouds, allows for more crisp images as the athmosphere on earth distorts the data less and less.

And that’s when Hubble came in.  One day, they had the idea to send a telescope into space, to escape all the issues of interference with earth’s athmosphere.  Hubble was big, it was about the size of a schoolbus.  Now they sent it up there and it was all very exciting, and the crew down on earth was impatiently waiting for the delivery of Hubble’s first pictures.  What they got was a real shock to all the scientists – and put a lot of people – from astronomers to politicians who had founded the project – into deep trouble.  Here’s what they saw.  On the right is what they SHOULD have seen, and on the left, the picture they got.

On the Left: What they saw.  On the Right:  What they should have seen.

On the Left: What they saw. On the Right: What they should have seen.

Now that was a problem.  NASA researched and researched until it finally understood the problem: the mirror had been the wrong shape.  Everything else inside the telescope had been built to work with the right shape.  And so they had to consider something rather unforseen and unthinkable at the time, to save their 2 billion dollars investment.
The solution?
The solution to fix the Hubble Mirror problem was to send men in space to do it

The solution to fix the Hubble Mirror problem was to send men in space to do it

This may look to you like something banal, and ordinary.  But when you think about it, it was very unlikely that this operation would be successful.  That Hubble telescope is revolving around the orbit of the Earth at a speed of 26 239 km/hr.  Combined to that, the mirrors in a telescope have to be extremely precisely aligned in order to obtain a correct picture.  Combined to the lack of gravity in space, and the fact astronauts are not astronomers (they don’t really do the whole telescope thing), then you can easily imagine just what a little chance this complex operation had of being of any success.
When the crew finished installing it, and the ground crew looked up expectantly at the screen to see how it had gone, everyone was stunned to see it was successful.  Almost impossible, and yet there it was, a clear, crisp, sharp image that surpassed anything they had ever seen from Earth — and new objects in the sky that had been to far for them to ever see from the telescopes on Earth.  A little marvel in itself.  And that picture they saw, was the one “they should have seen” from the beggining, the one in fact displayed on the right of the picture that shows what they first saw, above.
The story from here gets even more thrilling.  So Hubble is up,a nd it’s taking stunning pictures of the sky.  And one scientist goes, “Hey, this is the most powerful telescope in the entire history, why don’t we poitn it at the darkest patch of sky we can and see what it shows us?”    So they pointed it to this distant black patch of the sky.  And then things started appearing.  The picture they got was this one, which is different from the one you saw at the beggining, which was taken later.
Hubble Deep Space

Hubble Deep Space

So they ran it through those computer programs along with different things like spectroscopy.  They looked at the distance of the stars, their colors, their shapes, and many other things.  Their goal: to try to determine the universe’s expansion rate — at what speed was our universe growing.
“At first,my jaw dropped”, the engineer responsible for the analysis said.   “I thought there must be a mistake.   My screen was telling me that with the data it had, the universe had a negative mass.  The only way that that could be possible was if in fact the universe was speeding up, not slowing down, and we had been told that this was impossible.”
Why is this, you may ask?  Why MUST the universe be slowing down and thus why must those results have been wrong?   In one word, gravity.
Einsteins theory of relativity unveils a little problem

Einstein's theory of relativity unveils a little problem

In fact, Einstein himself, when he came up with his theory of relativity, knew that he was “wrong”.  He knew that, if the universe was staying constant (which was the assumption back then) then his calculations were off.  He countered that by a little variable, which I think he called Comsmic variable or something of the sort, to account for the “expanding force of the universe”  — because if the mass of the universe at its center was big enough to pull everythign in towards its center, for the universe to stay still (although today we know it actually does more than just resist that gravity and stay still – it actually is growing and expanding), it had to have some force that would balance that gravity off.  That force, he said, was neglectible on earth but added up throughout space, it really did have an incidence.

And so if Einstein’s theory was right and gravity was pulling things together, then with the mass we could see and estimate through spectroscopy (you look at special light emissions and decompose the spectrums to figure out which elements the body you’re observing is made of), the scientists could not explain why the universe was growing.  According to gravity it should be slowing down after that big bang, maybe even leading to an implosion eventually as the gravity pulled back everything in the center.

That marked the discover of Dark Matter, this invisible mass in the sky that is currently the only thing the scientists can think of to explain the picture taken by Hubble.

“Either Dark Matter is this new physics phenomenon which we’ve been unaware of for a really long time”, a scientist explains, “and if it really does exist, it’s a very thrilling and exciting discovery we’re about to experience, or Dark Matter does not exist and Einstein was wrong – or maybe not entire right – and we will have to revisit our models and understand how to adapt them to better describe the reality, which is also a thrilling prospect.  Either way, we’re on that treshold of an astronomical revolution.”

We live in exciting times!  And all this started by a telescope, and its deep sky photography.

Posted by: Corina Paraschiv | July 4, 2010

Under the Sea…

The sea is a fascinating place.  It covers 70% of our planet yet it’s one of the places we know the least about.  Sometimes I even get the feeling that we know more about the moon than we do about the sea!

The most we know about is the ocean surface — that is the upper 200 meters from the surface.

The ocean surface is the smallest portion of the ocean but it;s home to most species we know.  Probably because it’s the only place where there’s photosynthesis and also because it’s easier for us to look for marine life there.

As you go down deeper, you enter the Twilight Zone.  That’s somewhere between 200m and 1000m down — and that is where the light becomes really dim and dark…

Over there, most animals start looking transparent, having no color, because there simply isn’t anywhere to hide…

And then as you continue deeper and deeper you can get into the Deep Ocean.

I remember once seeing a really cool documentary by IMAX on extremophiles : how they went into caves to collect little specimens in the most remote areas where they’d think life would be impossible.  We learn so much by looking at where limits lie!

Posted by: Corina Paraschiv | July 4, 2010

How are we different from our ancestors?

Have a look at the sketches above and below.  The resemblance between these beings that existed 2.5 million years ago and ourselves is quite striking.

Yet it cannot be denied that we are quite different from these ancestors, too.

The key to understanding the difference is to understand abstraction : the modern human can conceptually bridge the gap between things.  For instance it can see things that are completely disconnected from each other such as a child petting a kitten, a wedding couple kissing or a mom holding a child and that individual will be able to put the word “love” to all three images although they are all very distinct.

This is something that primates – who I believe have a DNA that’s something like 92% similar to ours in some cases – are unable to do.

In fact, at a greater level, primates are unable to make generalizations.  Their memories and muscles can learn and stock a variety of things but they never make the connection between them and create patterns for them.

Now this was all covered in a great PBS documentary called Human Spark: Social Networks, but the interesting thing for me is to look at it from a language perspective.

All children are naturally apt to learn a mother language.  Where it becomes super interesting is : children make inferences regarding the syntax rules.  Take any language and watch what happens.

Say a child wants to say “The man took the dog for a walk”.  It is very common to hear children say something like “The man taked the dog for a walk”.  That is because they have heard the “ed” ending many times to designate the past tense, and they have now made an abstraction out of it.  They now unconsciously apply the rule every time they speak.

Interesting, isn’t it?

Posted by: Corina Paraschiv | March 26, 2010

Some creativity sparking thinggy

Every once in a while I find a video or an article or some drawing that just screams “CREATIVITY!!!” at me, and then I just have to share it with you guys.

The scene you see below is where it all takes place.  As you click on your keyboard, objects become alive, one by one, until you realize they all have their own lives while you’re calmly reading.

” Each day, we are surrounded by seemingly insignificant objects, taking them from one place to the other, or leaving them on a table for weeks, without paying any attention to them. We ignore or forget them, using things only when we need to, making sure they don’t interfere or inhabit our space. But what if they were not so stable and subservient? What if they could swivel, bounce or even fly. And what if they did so all at the same time? We want to imagine a place where objects could live and move, harmoniously, and of their own accord. Without interfering with each other these objects would bounce, roll, turn and cross each other’s paths.  This experiment is about re-discovering our daily surroundings. Each object is assigned to a letter on the keyboard, and can be activated or deactivated at any time.”

Have I piqued your curiosity enough?
What are you waiting for?  Have a go!

Posted by: Corina Paraschiv | March 25, 2010

Golden Ratio… found in Baghdad too?

The mathematician, al-Samawal, working in Baghdad, Iraq, around the year 1150, gives an expression for the Golden Ratio that looks much different from the expression we use. Is he correct?

Posted by: Corina Paraschiv | March 9, 2010

Delaying Gratification: The M&M test

It was 1995 under the Mexican sun and I was reading Emotional Intelligence by Daniel Goalman in between a dip in the sea and a delicious grilled chicken or quesadilla snack at the beach bar.  That book was quite thick and had loads of stuff in it but I do remember this one passage pretty distinctively : a researcher had placed some chocolate in front of kids and told them that if they waited until he’d come back, they’d receive double the amount of chocolate.  If they ate it before he’d come back, then they wouldn’t get anymore.   A later study showed that those who were able to wait until the adult came back into the room did better as adults.  Interesting study.

Now the thing I’ve never seen was what does it look like when kids are in the room on their own, with the treat in front of them.  Oh how entertaining this is!!  Have a look!

Posted by: Corina Paraschiv | March 9, 2010

Cartoons Swingin’

In the 1940s swing dancing was extremely popular and it seems even pop culture, such as cartoons, took it up!  It’s always fun of course, to try and learn new swing moves by watching some of the pros, but it’s been a real surprise and delight to see my favorite dance protrayed in cartoons.

This Donald Duck clip features lots of inspirational solo moves which you can pick up… or just watch for the fun of it.  Quite entertaining!

In this one, a more “serious” version – but still funny – you see young people dancing to balboa and doing swing outs as well as ariels.  Quite entertaining!  And I prefer that kind of music to the previous one!

Enjoy and let the creative juices flow!

Posted by: Corina Paraschiv | March 9, 2010

Benford’s Law : How Credit Cards Detect Frauds

So you try to purchase something at the local store and they tell you your credit card’s not working.  You phone company and it turns out your card’s been making fraud purchases and that’s why VISA/Mastercard/American Express/Whatever-your-company blocked it!

But did you ever stop to wonder how they knew about this?   It’s Benford’s Law (amongst other things).
Numbers in the natural world have a very special distribution.  In your math class in high school, you probably heard about the normal distribution.  Well the Bendford’s law follow a completely different distribution.  It goes like this (off Wikipedia) :

Leading Digit     Probability
1              30.1%
2              17.6%
3              12.5%
4               9.7%
5               7.9%
6               6.7%
7               5.8%
8               5.1%
9               4.6%

Now let’s see in more details how this works.  The following video is taken from the website called Kirix.

Now you know!


					
Posted by: Corina Paraschiv | March 8, 2010

The Poetry-Geek

Same guy, just gets funnier :p

Posted by: Corina Paraschiv | March 8, 2010

Oscar Movies Parody

And the winner of the Oscars this year is…

Hey I couldn’t let the Oscars pass with at least a little bit of humor about them, could I!

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