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2.  SciCast Tip of the Week
Keeping up with the Joneses might be a domestic nightmare, but keeping up with SciCast is a whole lot easier. There’s this column, of course, lovingly hand-delivered to your inbox every week by our crack team of email robots.
But now (NEW! FRESH!) there’s also the SciCast Blog, an ever-changing melting-pot of ideas, inspiration, links, examples, equipment reviews, help, and advice.
It’ll be the first place you’ll hear about our forthcoming downloadable films, too. Which we know we’ve been promising for months, but is actually quite close to happening, now. Honest.
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3. Stump the Scientist
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 Last week’s stumper was from Jude in Shropshire who asked:
“Why is it, when the weather is cold, we feel like we need to go to the loo more often? Is it to do with blood supply & the bladder being deprived/constricted?? Or is it just me?”
J Bond replies
“We do need to have a wee more often when it's cold. This is due in part to vasoconstriction (when blood vessels near the surface of the skin constrict to allow less blood to flow through them so that less heat is lost to the outside). Vaso constriction cause there to be a greater volume of blood in the inside of the body. This is interpreted by the body as there being too much water in the blood so the production of ADH is stopped, causing more water to be excreted through the kidneys in the urine - hence the greater need to wee!”
Romaine Hervey adds
“The obvious answer is: Because in the cold -- specifically when we go from a warm environment to a cold one -- we shut down circulation to the skin; particularly in the extremities. This is a fast-responding, fine adjustment, method of temperature control, though not actually with a wide range of control. The shut-down in the peripheral circulation makes the deep part of the circulation sense over-filling.”
Peter Bayley-Bligh, Joy Moise and Helen Hare all understood that it was because you sweated less in the cold weather and therefore went to the loo more to remove more water/urea from your system. So is this a myth? Please can someone shed a light? We found a website on the subject but after reading the sentence ‘Talk lovingly to your kidneys…’ we beat a hasty exit.
If you can help or have a burning question of your own then send us an email with STUMP THE SCIENTIST in the subject line to planet-science.news@nesta.org.uk
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4. Activity of the Week
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Rattlebacks
 You will need:
- A plastic spoon. Preferably a large one, like a dessert spoon.
- Some Plasticine, modelling clay, Blu-Tack, or similar. Play-dough is too light, sorry.
- A plastic ruler. 30cm is fine, but 20cm is better if you can find one.
What you do:
- Snap the bowl off from the handle of the spoon (be careful to aim it away from yourself when you do this, in case it fires splinters), and fill it with a big blob of Plasticine. You want it to look like a heaped spoonful of Plasticine.
- Now imagine you hadn't snapped the handle off, and line the spoon up with the ruler. Slide one over the other until the bowl of the spoon is dead-centre of the ruler. In a moment, you're going to push the two together so the Plasticine sticks them, but just before you do, twist the bowl of the spoon. Just turn it, ever so slightly - five or ten degrees is plenty. Now squidge them together
- You'll have to juggle everything around a bit so that when you put your rattleback on a table, spoon-side down, it balances nicely. You want the ruler to rest parallel with the table, without one end touching or one side being especially lower than the other. Smudge the spoon around until you've got that. Done? Good
- Now, spin your rattleback. Give it a good flick with your fingers so it spins several times, and see what happens. When it stops, try spinning it in the other direction.
What's going on?
What you should see is that your rattleback is quite happy spinning in one direction (either clockwise or anticlockwise), but if you spin it the other way, it objects. It will start to rock, and then rattle, and then - amazingly - it'll stop spinning, and simply rock back and forth like a see-saw. If you're lucky, it will even start to rotate the other way.
When something is spinning it has angular momentum, and one of the laws of the universe is that angular momentum is conserved. Angular momentum - basically the speed with which it is spinning - only changes when a force acts on it.
What we might expect is that the spinning rattleback will slowly slow down and eventually stop due to the force of friction. This is indeed true if you spin the rattleback in the direction it wants to go in. If you spin it in the opposite direction it stops more quickly and may spin back the other way. There is clearly a force in this picture too, and it has to be friction as long as you keep your hands away.
For the rattleback to work it has to be a specific shape. It needs to be long and thin with a long curve running one way and a short curvier curve running at right angles to it. You must have a different mass distribution running along the rattleback than across it (the spoon satisfies both these points). Finally the mass of the rattleback can't sit symmetrically about either the length of the rattleback or its width - it needs to be slightly skewed (which is what you did by twisting the spoon a little before sticking it on).
If the base of the rattleback were uniform, friction would act directly opposite the motion. But the uneven mass distribution means that friction may point at an angle to the motion. For a correctly constructed rattleback there will be a vertical component which will start to make the rattleback rattle.
When spun in the unfavourable direction the entire rotational energy will slowly be transferred to this up and down motion. Once the rotation has stopped, the rattleback rocks up and down. Friction also opposes this motion, but instead of pointing along the line of the rocking the friction force is off centre - it does not point to the centre of mass. The result is an uneven force, a twisting motion, which starts the rattleback moving in the opposite direction - its favoured direction.
But why does it spin so happily in one direction but not the other? This pitching up and down only happens when the rattleback is spun in its unfavourable direction. When spun in its preferred direction the pitching happens across the ruler - this is usually known as rolling. This is a smaller motion and would take longer for it to drain the energy out of the rattleback's spin. The rattleback tends to lose its energy to normal everyday friction before there is time for the rolling instability to take over.
Special safety advice
Be careful when breaking the spoon from the handle, the plastic can splinter and the cut end can be sharp.
This film clip can be viewed at Planet SciCast.
Keep checking back for new films and, whilst you’re about it - how about submitting one of your own? Closing date for this year's SciCast awards is 4th Jan 2008.
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5. Mouses at the Ready
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 This week we’ve got a great giveaway for you. Ten copies of the December Flipside magazine. How’s that for some festive reading whilst you’re curled up beside a roaring fire, a hot steaming cup of hot choc in your hand (don’t forget the whipped cream and marshmallows!)?
If you’d like to win a copy then email us with your name and address, and the words ‘FLIPPIN GOOD READ’ in the subject line, to planet-science.news@nesta.org.uk.
The draw will take place at 5pm on Wednesday 12th December.
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The Sticky Quiz
Stick it in your diary – Must enter the Planet Science November Sticky Quiz. Time’s running out. We mean it! There’s a new super-duper quiz straining at the leash to get out so make the most of it while it lasts…
Answer all ten questions correctly and you could win a set of floor/garden/park/beach sized pick up sticks!
Ready? Steady?
Get stuck in!
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Free NLN Stem DVD!
This free DVD contains a unique selection of e-learning resources taken from the full on-line National Learning Network (NLN) Materials suite.
Specially chosen for the East of England STEM Support Centre by the Science Learning Centre East of England to support the delivery of STEM subjects, the selection includes around 500 learning objects covering Science, Technology, Engineering and Maths.
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Blogging from the Bottom of the World
When Ernest Shackleton embarked on his attempt to cross Antarctica in 1915, radio technology wasn't sufficiently developed for him to keep in contact with Britain. Now a group of gap year students taking part in an expedition in the Antarctic region will be able to post regular updates to a blog on physics.org, an Institute of Physics website that aims to show a different side to physics.
The expedition is being led by the British Schools' Exploring Society) who celebrate their 75th anniversary this year.
The 11 young explorers are currently on South Georgia, a remote island in the South Atlantic, where they are carrying out a variety of scientific work, including bird population surveys and mapping of glaciers, as well as a search for the stove discarded by famous explorer Ernest Shackleton when he traversed the island in 1916.
The expedition coincides with International Polar Year, a large scientific programme focused on the Arctic and the Antarctic from March 2007 to March 2009.
The Antarctica blog is online now and runs until 30 December, when the expedition returns to the UK. Readers can submit questions to the expedition members, whose pictures and biographies are up on the site.
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Teachers TV
Teachers TV is a free-to-air channel available on digital satellite and digital cable television 24 hours a day, seven days a week and on Freeview from 4-5pm daily. Here’s an example of a programme:
Aim Higher – Focus on Science
Three hundred Year 10 students attend a science fair at Barnsley College. Organised by Aimhigher, the fair hosts workshops from a variety of universities and lecturers. Sheffield Hallam University introduces the students to a murder mystery game in which a suspiciously stained T-shirt is analysed, while the University of Huddersfield's focus is on beauty products, allowing pupils to make their own. The idea of the fair is to encourage students to consider studying science at university, but will it succeed?
For more information visit the Teachers TV website.
Next airing on TV:
Wed 12 Dec 08:15
Wed 16 Jan 08:00
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Win £5,000 for your school!
Take up the Faraday interactive challenges and compete for fantastic prizes. The IET Faraday is an exciting year-long programme exploring science in action for all secondary students.
Science in Action
- Create your own challenge videos and compete with schools around the country
- Use your problem solving and creative skills to respond to our scientific challenges!
Enter as many challenges as you like and submit your videos online.
Vote for your favourites by visiting the video gallery and win prizes for you and your school.
The deadline is 14th December and winners will be announced the following week.
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7. Recommended website of the week
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Stuck for ideas for science lessons? Tired of the same old resources doing the rounds year after year? Then you need an update – or should that be Upd8? upd8.org.uk is a free downloadable science resource from the ASE. It aims to make science more topical by exploring the science behind the stories in the news. Try the Winter Olympics activity. It links to QCA Unit 9L pressure and moments. Readers in Scotland, Wales and Northern Ireland may have to consult their own curricula to see where this fits. Sorry about that. Does anyone know of a site that 'translates' English science curriculum links into those for Scotland, Wales etc? We'd love to know it! Back to Upd8 - In this activity students look at how skating and skiing work, before practising pressure calculations using skates and skis as examples.
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Remember last week when we were offering you three family tickets for the film Santa v the Snowman 3D at the IMAX?
The lucky winners are Maria Clarke of Kent, Peter Dunkin of Mitcham and Katie Sherval of Surrey. Oooh please let Santa win – we can’t bear the thought of that lump of icy snow getting one over the Big Man himself. And who would deliver the presents? Lip quivers at the thought. Well done everyone!
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9. Joke of the week
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They say you get wiser as you get older. We have Dale Robinson to thank for this one…
An old poodle had lived on its guile and wits for years in the jungle. One day he noticed the leopard on the prowl for a meal. Not knowing where it could safely hide, the poodle spots some old bones on the jungle floor. He grabs one up and starts to suck on it. As the leopard approaches, the poodle says in a loud voice" Wow I just love leopard meat, and they're such easy animals to catch."
The leopard stops in its tracks, and tiptoes off into the jungle before the poodle spots him.
A monkey, who had watched the whole event, thinking he can get into the leopard's good books, goes running after the leopard to tell him what he's seen.
The leopard, when he hears the story, is furious. He tells the monkey to climb on his back, and goes racing back through the jungle to teach the poodle a lesson.
The poodle sees them coming, turns his back on them and picks up a bone.
As they get really close, the poodle says in a loud voice, "Where's that blooming monkey, I sent him off an hour ago to bring me another leopard."
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This week saw the first birthday of Knut the polar bear. He hit the headlines when his mum rejected him soon after birth. Weighing in at 17 stone, he may no longer be cuddly - but he's still pulling in the crowds at Berlin Zoo. He even has his own blog and TV show and has appeared on the cover of loads of newspapers and magazines. David Beckham watch yer back!
Brrr!!! Winter is here (see 5 Kingdom’s winter makeover – it’s even snowing, Aw!), and Planet Science has got some frosty new creature masks from the 
