A Month of Spectacular Space Weather January 25, 2012
Posted by Mr G in Astronomy, Physics, Space Travel, TV.Tags: aurora borealis, aurora photos
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The Sun has been pretty busy lately, with lots of flares and coronal mass ejections sending high energy particles flying towards the Earth. These can cause problems, both in space and on the ground.
Fortunately the Earth’s magnetosphere deflects most of these away from us. But the field comes back to Earth at the poles and these high energy charged particles come rushing down into the atmosphere (in some cases accelerated by the Earth’s magnetic field).
These particles “excite” the atoms in the air by giving the atoms electrons more energy, which then get rid of the energy again as light. Blue or Red for nitrogen (70% of the air) and Red and Green for the oxygen.
At high altitude oxygen red dominates, then oxygen green and nitrogen blue/red, then finally nitrogen blue/red when collisions prevent oxygen from emitting anything. Green is the most common of all auroras. Behind it is pink, a mixture of light green and red, followed by pure red, yellow (a mixture of red and green), and lastly pure blue.
Just like iron filings line up along a magnetic field, so do the charged particles. We get sheets of air glowing when hit by the particles following the Earth’s field lines, drifting and swirling around. We call them Aurora. Aurora Borealis (a.k.a. The Northern Lights) and Aurora Australis (The Southern Lights).
Here is a BBC Stargazing Live video explaining Aurora – it’s aimed at Primary kids so it’s kept nice and simple.
Below is a slide show of Aurora photos taken during January 2012.
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Mr G
Sources: Wikipedia, BBC News, BBC Stargazing Live, Various Newspaper websites.
Is anyone out there…? Chance they are just got bigger! January 13, 2012
Posted by Mr G in Astronomy, Physics.comments closed
The existence of life outside our planet just got a bit more likely.
Following years of finding planets around other stars, a new study thinks that every star has planets which form from the remaining material in the gas/dust cloud that formed the star. The study – originally published in Nature magazine is also discussed in this BBC News article.
That means there are likely 10 Billion (10,000,000,000) planets that are like Earth in size. Many of those could be the right temperature and have the right chemistry for life to have developed.
One thing to bear in mind – we currently don’t know how to travel faster than light so even if aliens do exist – unless they do know how we might never meet them.
Mr G
Sources: Nature, BBC News
Stoke Earthquake… January 12, 2012
Posted by Mr G in Geology, Local Science.comments closed
Today an earthquake hit the Newchapel area of Stoke on Trent.
Magnitude 2.4 is not massive on the scale of earthquakes – but it is one of the more noticeable ones for this area.
Most of the earthquakes in North Staffordshire are to do with old coal mines shifting and settling. But this one is to do with the plates of rock in the Earth’s surface shifting. Although the UK is away from the edges the large continental plates (so no large earthquakes) – there are still big pieces of rock moving around. This is why we have mountains and hills in certain parts of the country while others are fairly flat.
The south end of Stoke on Trent (Barlaston on this map) is right at the point where two plates are moving – above that are the hills of the Staffordshire Moors and the Derbyshire Dales. To the west – the Malvern Hills and the Welsh mountains. To the east are “concealed” mountains – the mountains possibly buried by sedimentation when this was sea bed.
The sudden movement of the rocks will release lots of energy (earthquake) that has built up over time. As the sliding rocks get “jammed” and their movement stops, stored energy builds up.
In the UK movement of faults between plates of rock are generally slow, but over years the effects can be seen.
Mr G
Sources: BBC News, Quarterly Journal of Engineering (images)
