October162012
An artist’s impression of a newly discovered star system, in which the planet (the black dot on the white star) is in a system of 4 stars. Over 800 planets orbiting stars other than the Sun (called exoplanets) are now known, meaning we are certainly not special in terms of having planets! 
This planet (and many others like it) were found by measuring the tiny drop in the brightness of a star as the planet passes between it and Earth. This of course will only work if the orbit of the planet will make it pass between us and the star, and so this is only one of many methods used to detect extrasolar planets. So far it has been difficult to detect planets the same size as the Earth because Earth is, well, small, making any changes an earth-sized planet will cause to its star be miniscule.
This planet would have 4 suns in its sky, depending upon the time of day and year, and would make for a spectacular sight, although when you have the more distant stars lighting up what should be night time, I think the novelty may wear off!
If you want to have a go at finding a planet, you can! Planet Hunters has a load of telescope data for thousands of stars which people can examine for evidence of planets. It’s fun.

An artist’s impression of a newly discovered star system, in which the planet (the black dot on the white star) is in a system of 4 stars. Over 800 planets orbiting stars other than the Sun (called exoplanets) are now known, meaning we are certainly not special in terms of having planets! 

This planet (and many others like it) were found by measuring the tiny drop in the brightness of a star as the planet passes between it and Earth. This of course will only work if the orbit of the planet will make it pass between us and the star, and so this is only one of many methods used to detect extrasolar planets. So far it has been difficult to detect planets the same size as the Earth because Earth is, well, small, making any changes an earth-sized planet will cause to its star be miniscule.

This planet would have 4 suns in its sky, depending upon the time of day and year, and would make for a spectacular sight, although when you have the more distant stars lighting up what should be night time, I think the novelty may wear off!

If you want to have a go at finding a planet, you can! Planet Hunters has a load of telescope data for thousands of stars which people can examine for evidence of planets. It’s fun.

4AM

A long absence kinda curtailed this blog for a while - new job, new country and various bits of bad news. I think it should all have settled down enough now to start doing this again, it is something I really started to enjoy before. I will try to update a few times a week.

July152012
This little graph here is what all the excitement about the Higg’s boson boils down to. I explained the need for the Higg’s boson (as far as I understand it, I am not a particle physicist, I look at molecules!) below, and here I will try to explain why everyone is so excited about the results!
You see that little bump, at around 125? That is from a new particle, which is suspected to be the Higg’s boson. Looks pretty unimpressive at first glance! A little bump not much above the background may not seem much to be excited over. But the important thing is that the chance of this being measured by chance is 1 in 3,500,000. 
I’ll explain exactly what was measured. The Higg’s boson is unstable, and can decay in many different ways. The decay studied here is when it decays into two photons - particles of light. The decay of the Higg’s is not the only way in which two photons can be created, and this is what the majority of the signal seen in this graph is, everything that follows that nice smooth decreasing curve in fact. However, when you look for two photons with a combined energy the same as the mass of the Higg’s boson, you see an extra bit of signal! That extra bit of signal is what the physicists have been searching for and have found. Its amazing how a single graph can have so much information in it, I am always amazed by this.
The key point is that two different experiments how found the same thing at the same energy. This makes it even more unlikely that this is just down to chance. It’s cutting edge physics that everyone can grasp, and I love it.

This little graph here is what all the excitement about the Higg’s boson boils down to. I explained the need for the Higg’s boson (as far as I understand it, I am not a particle physicist, I look at molecules!) below, and here I will try to explain why everyone is so excited about the results!

You see that little bump, at around 125? That is from a new particle, which is suspected to be the Higg’s boson. Looks pretty unimpressive at first glance! A little bump not much above the background may not seem much to be excited over. But the important thing is that the chance of this being measured by chance is 1 in 3,500,000. 

I’ll explain exactly what was measured. The Higg’s boson is unstable, and can decay in many different ways. The decay studied here is when it decays into two photons - particles of light. The decay of the Higg’s is not the only way in which two photons can be created, and this is what the majority of the signal seen in this graph is, everything that follows that nice smooth decreasing curve in fact. However, when you look for two photons with a combined energy the same as the mass of the Higg’s boson, you see an extra bit of signal! That extra bit of signal is what the physicists have been searching for and have found. Its amazing how a single graph can have so much information in it, I am always amazed by this.

The key point is that two different experiments how found the same thing at the same energy. This makes it even more unlikely that this is just down to chance. It’s cutting edge physics that everyone can grasp, and I love it.

5AM

Apologies for the absence

I did plan to keep this whole thing up to date a lot more than I have. Unfortunately it turned out writing my thesis got in the way rather, and I was unable to keep up! My thesis is written now, which allows me to get back to the things I really enjoy, like this =}.

On the plus side, I have several months of interesting science to catch up on and post on here =}

February112012

The Higg’s boson, what?

You may or may not have heard that scientist have found indications of the existence of the Higg’s boson at CERN, with a mass of around 125 GeV (the giga electron volt is about 0.000000000000000000000000001 kg, or about a million billion billion times less than a grain of rice) . 

Anyway, I wanted to try to explain why on earth there is so much fuss over this particle. Well, it is all because we don’t understand where mass comes from. It is probably something you haven’t really thought about before, because everything just has it, but when you think about it it is a little odd that things like electrons and quarks (the things protons and neutrons are made from) just happen to have a certain mass (0.51 MeV for electrons, 2.4 MeV for up quarks, 4.8 MeV for down quarks). Well that is where the Higg’s boson steps in. The story gets a little bit tricky, and I don’t fully understand all of this myself in gory detail, but I will try to explain this.

The Higg’s boson is predicted by the Standard Model of particle physics to explain why the fundamental forces (electromagnetic, strong, weak and gravity) don’t all have the same strength (in truth, it is just the EM and weak forces, but it too much to go into, and if you are interested read this link). Basically, the presence of the Higg’s boson breaks the symmetry between the strength of the forces, and it does this in a clever way.  At high energy the strength of the EM and weak force is the same and they are together referred to as the electroweak force. It is the fact that they are the same at high energy but different at low energy that we are trying to explain here. 

So how does the Higg’s boson do this? It interacts with the electroweak force in such a way that one part of it, the EM force, stays like it was before. The other part, the weak force interacts with the Higg’s boson, causing the particles that make up the weak force (W and Z particles) to become massive. Why this is then cool is because the Higg’s boson must also interact with the electrons and quarks in the same way, giving them mass! So we explain two things with one idea, which is always neat. The problem is, the Standard Model doesn’t tell us the mass of the Higg’s boson, so it is like looking for a needle in a haystack. However, if the Higg’s boson is found, it basically means that the Standard Model of particle physics is correct (at least so far as no new data is discovered that it can’t explain), and this would be a massive thing to know. On the other hand, if the Higg’s boson isn’t found, it means that the Standard Model is wrong, and particle physicists will have to come up with a whole new theory of particles, which would be amazing!

I hope I could perhaps lift some of the mystery surrounding the Higg’s boson, because you do read a lot of crap about it.

February102012

I spoke about the Aurora previously, in an earlier post (and I only have a few so you can go read up on it =}) but this video is pretty spectacular. The Aurora Australis from space. It is compiled from a series of still images taken by astronauts aboard the international space station. It quite literally made my draw drop. Stunning video.

February22012
This isn’t really new science, or a science picture, I just think it is really like awesome to understand how little of what happens around us we can actually perceive!
Human eyes are generally sensitive to light from around 390nm (blue) to 750 nm (red). That is a truly tiny window we can see in, a 360 nm (thats 0.000000360 m) range, when EM radiation can have wavelengths of pretty much any size. We see almost nothing that happens in the world.
Human ears are generally sensitive to sound from 20 Hz to 20 kHz (20,000 Hz), which is again not really the largest of ranges when you think that sound of any frequency can exist.
The reason why we are like this is because we evolved on planet around a star that has maximum brightness in the visible part of the EM spectrum, and so that is the light of which there is the most. I assume hearing evolved for similar reasons - that most noises of importance on earth are in this particular range.

This isn’t really new science, or a science picture, I just think it is really like awesome to understand how little of what happens around us we can actually perceive!

Human eyes are generally sensitive to light from around 390nm (blue) to 750 nm (red). That is a truly tiny window we can see in, a 360 nm (thats 0.000000360 m) range, when EM radiation can have wavelengths of pretty much any size. We see almost nothing that happens in the world.

Human ears are generally sensitive to sound from 20 Hz to 20 kHz (20,000 Hz), which is again not really the largest of ranges when you think that sound of any frequency can exist.

The reason why we are like this is because we evolved on planet around a star that has maximum brightness in the visible part of the EM spectrum, and so that is the light of which there is the most. I assume hearing evolved for similar reasons - that most noises of importance on earth are in this particular range.

January282012
This is a slightly more complicated one to explain easily and quickly, but it is amazing. That is a map of electrons in a molecule, called pentacene. More technically, it is called a molecular orbital. The light areas are where you are likely to find an electron, and the dark areas are where you are not likely to find an electron. The left hand side are experimental measurements using a STM (i will explain that in a moment) and the right hand side are calculations. Look at them, they are the same!!
The experiment is awesome, basically a STM is a tiny needle, a few atoms across. You scan this across a surface (or a molecule) and depending on the distance from the surface (or in the case, the likeliness of an electron being nearby) there is a current formed in the needle. Measuring this current, you can measure where the electrons are.
This is so awesome because this has never ever been seen before. Molecule are tiny, about 0.00000000001 m across. So to be able to see something so small, is just so amazing. Also, this is actually seeing quantum mechanics in action. What those white areas are is a picture of a wavefunction. I can’t go into that in this post, but tomorrow I will expand on this!

This is a slightly more complicated one to explain easily and quickly, but it is amazing. That is a map of electrons in a molecule, called pentacene. More technically, it is called a molecular orbital. The light areas are where you are likely to find an electron, and the dark areas are where you are not likely to find an electron. The left hand side are experimental measurements using a STM (i will explain that in a moment) and the right hand side are calculations. Look at them, they are the same!!

The experiment is awesome, basically a STM is a tiny needle, a few atoms across. You scan this across a surface (or a molecule) and depending on the distance from the surface (or in the case, the likeliness of an electron being nearby) there is a current formed in the needle. Measuring this current, you can measure where the electrons are.

This is so awesome because this has never ever been seen before. Molecule are tiny, about 0.00000000001 m across. So to be able to see something so small, is just so amazing. Also, this is actually seeing quantum mechanics in action. What those white areas are is a picture of a wavefunction. I can’t go into that in this post, but tomorrow I will expand on this!

January272012
That girl (I assume girl, I don’t know for sure) likes butter! I am sure everyone has held a buttercup to their chin to see if it reflects yellow. Now we know why the flower is so good at reflecting light.
There are two things going on here, all down to the structure of the petals. The petals have an outer layer of cells which are partially transparent, and reflective, acting like a mirror. The second thing is a layer of pigment, which reflects yellow light. When you combine these two effects, you get this yellow shine! Light from the sun will be reflected onto your chin if you hold it the flower at the right angle. Because of the pigment, the light will be yellow. This makes your chin light up.
Nature is just awesome!

That girl (I assume girl, I don’t know for sure) likes butter! I am sure everyone has held a buttercup to their chin to see if it reflects yellow. Now we know why the flower is so good at reflecting light.

There are two things going on here, all down to the structure of the petals. The petals have an outer layer of cells which are partially transparent, and reflective, acting like a mirror. The second thing is a layer of pigment, which reflects yellow light. When you combine these two effects, you get this yellow shine! Light from the sun will be reflected onto your chin if you hold it the flower at the right angle. Because of the pigment, the light will be yellow. This makes your chin light up.

Nature is just awesome!

January252012
A beautiful picture of the night sky taken at the Paranal Observatory in Chile shows the Comet Lovejoy. Discovered by amateur astronomer Terry Lovejoy in November 2011, which just is amazing because it shows amateur astronomers can discover (and name) amazing objects still!
This comet is a member of a family called the Kreutz Sungrazers, named unsuprisingly because they approach the sun very closely. This one entered the Sun’s corona (outer atmosphere of the sun, made of plasma and extending several million km into space) in December 2011, from which it emerged and continued its lonely journey through the solar system. It won’t be back for 600 years.
The Kreutz Sungrazer comets are thought to come from a large comet that disintegrated some centuries ago, and it is thought that another large, daytime visible, undiscovered member of this family could still be waiting to pass through the solar system.
I love space.

A beautiful picture of the night sky taken at the Paranal Observatory in Chile shows the Comet Lovejoy. Discovered by amateur astronomer Terry Lovejoy in November 2011, which just is amazing because it shows amateur astronomers can discover (and name) amazing objects still!

This comet is a member of a family called the Kreutz Sungrazers, named unsuprisingly because they approach the sun very closely. This one entered the Sun’s corona (outer atmosphere of the sun, made of plasma and extending several million km into space) in December 2011, from which it emerged and continued its lonely journey through the solar system. It won’t be back for 600 years.

The Kreutz Sungrazer comets are thought to come from a large comet that disintegrated some centuries ago, and it is thought that another large, daytime visible, undiscovered member of this family could still be waiting to pass through the solar system.

I love space.

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