For noen dager siden ble jeg oppringt av søte og hyggelige Andrea i NRK Ukeslutt, som lurte på om jeg kunne være med å snakke litt om atomvåpen. Anledningen var selvsagt hele situasjonen med Nord-Kora og Guam og USA, og selv om jeg på ingen måte er noen ekspert på Nord-Koreas atomvåpen kan jeg en del sånn generelt om atomvåpen, så det ville jeg gjerne snakke om 🙂

Atomvåpen har vært tatt i bruk to ganger: i Japan, i Hiroshima og Nagasaki, i 1945. Det er fra disse to episodene vi har mesteparten av kunnskapen vår om denne typen våpen, og hvordan de virker og hva slags type ettervirkninger de har, og det er selvsagt ganske relevant når man skal snakke om hva atomvåpen kan gjøre mot noen, og hva man eventuelt kan gjøre selv for å "beskytte" seg.

Før jeg skulle møte Andrea tok jeg frem en av mine favorittbøker - Radiation and Reason -The Impact of Science on a Culture of Fear, av Wade Allison, for å friske opp min egen kunnskap og ha tallene klare når jeg skulle uttale meg.

Denne boken ER så bra og interessant og spennene! Er du interessert i radioaktivitet og stråling, og effektene av dette så MÅ du bare ha denne boken! I Ukeslutt-innslaget så snakker jeg jo hovedsakelig om Hiroshima og Nagasaki, siden det altså er disse to episodene vi har som kan fortelle oss mest om hvordan stråling etter et atomvåpen faktisk kan påvirke mennesker. I boken står det masse om Japan og bombene, og jeg har lyst til å oppsummere noen tall som kanskje kan være en overraskelse(?) for en del lesere:

  • det levde 429 000 mennesker i Hiroshima og Nagasaki før bombene, og 103 000 døde i eksplosjonen, brannen som fulgte, og på grunn av store stråledoser sånn rett etterpå
  • hva som skjedde mellom 1945 og 1950 er litt uvisst, men fra of med 1950 har man fulgt opp 283 000 overlevende
  • sannsynligheten for å dø av kreft hvis man først hadde overlevd til 1950 er ca 8%, mens sannsynligheten for å dø av kreft på grunn av stråling kun var 0.4% (dette har vist seg å være mindre enn det man først kanskje fryktet)
  • for de som fikk stråledoser under 100 mSv er det ingen ekstra risiko for kreft
  • mellom 1950 og 2000 døde 296 mennesker av leukemi; dette er 93 fler enn det man forventer hvis man ikke hadde vært utsatt for den ekstra strålingen (stråling er ansvarlig for i underkant av 100 ekstra leukemi-dødsfall på 50 år, altså)
  • når sannsynligheten for å dø av strålingsindusert leukemi er 1 til 1000 på 50 år betyr det at i gjennomsnitt så blir forventete levealder redusert med 2 uker
  • for de som fikk stråledoser på 1000 mSv og mer (dette gjelder 3% av de overlevende), ble gjennomsnittlig forventet levealder redusert med ca ett år
  • mellom 1950 og 2000 døde det 10 127 mennesker av andre krefttyper enn leukemi (blant de overlevende) - dette tilsvarer 480 ekstra kreftdødsfall på grunn av stråling

At strålingen ikke akkurat er det du bør bekymre deg for når det gjelder atomvåpen betyr selvsagt på ingen måte at atomvåpen er greit, eller ikke noe skummelt - for det syns jeg absolutt at de er...men det er fordi de har så enorm ødeleggelseskraft der og da, ikke fordi noen flere vil få kreft etterpå.

Hele reportasjen ble sent i Ukeslutt på NRK i går, og kan høres HER

PS: Fra om med den uken som begynner i morgen skal jeg være skikkelig back in business - jeg har vært på halv tolv i veldig lang tid nå, og det er bare å beklage! I skrivende stund sitter jeg faktisk blant annet å forbereder Ukens Formel - fredagsspalten min. Jeg vil også samle sammen spørsmål og svare i videoblogg, så hvis det er noe du lurer på, eller vil ha utdypet er det bare å rope ut! Anders blir selvsagt gjerne med for å snakke fysikk♥

Forrige gang jeg var innom her fortalte jeg bare ganske kort at jeg skulle på P2 og snakke om jod og jod-tabletter. Bakgrunnen for det var at det skal kjøre atomubåter langs kysten, og derfor mener noen at det er viktig at det er jod-tabletter tilgjengelig i hele landet. Som jeg nevner i radioinnslaget (link til dette nederst i innlegget) så syns jeg saken dette startet med, altså ubåtene, er veldig underlig...

Saken er nemlig den, og det glemte jeg selvsagt å si på radioen (da snakket jeg jo mest om hva jod er og hva som skjer med jodtabletter - hva er greia med jod-tabletter, liksom): Jeg kan ikke fatte og begripe at disse ubåtene skal være noen som helst grunn til at jod-tabletter skal være jevnt fordelt i landet. La oss si at det faktisk blir et radioaktivt utslipp fra disse ubåtene, da, så vil dette skje i havet. Da vil naturlig nok det radioaktive jodet (som også vil være en del av det radioaktive utslippet) gå inn i næringskjeden vår gjennom fisken. Dette er ikke et problem for oss, og løses helt enkelt med fiskeforbud i det området der utslippet har vært, i noen uker (jod-131 har en halveringstid på 8 dager, så etter bare en drøy uke er det kun halvparten igjen av den opprinnelige radioaktiviteten). Uten å spise fisk fra det området der det er kommet radioaktivt jod vil du heller ikke få radioaktiv jod i deg. Problem løst. Poenget er at det ikke ville være noe poeng med jod-tabletter (en annen kollega av meg utbrøt hva slags schnapps-idé er dette?!? så det er ikke akkurat bare jeg som syns dette høres tullete ut).

Fiskeforbud ville det forresten uansett GARANTERT ha blitt, selv om man delte ut jod-tabletter...

 


Ina og Kine oppsummerer egentlig hele denne saken i et par Twitter-meldinger:

 

 

Jeg liker spesielt godt

også tok media helt av og bare "Faren er stor!"

 

Dessuten, hvis du er bekymret for radioaktivt jod burde du passe på at du spiser så du får i deg nok jod gjennom kostholdet ditt. Hvis du ikke har mangel på jod i utgangspunktet vil du ikke ha behov for jod-tabletter uansett. Så: drikk melk, spis fisk - spesielt torsk, sei, og makrell ♥

 

HER er innslaget fra Studio 2  og HER er et tidligere innlegg jeg har skrevet om jod-tabletter.

Still gjerne spørsmål hvis jeg skal utdype noe mer rundt dette - eller andre ting som er uklart eller skummelt eller rart med stråling. Koz og klemz ♥

 

 

 

 

Hei fine ♥

En av tilbakemeldingene jeg fikk etter at jeg spurte hva dere ønsker dere på bloggen fremover, var at jeg burde ha faste innlegg med ukens formel. Min aller første reakjson var at nei, det er faktisk for nerdete – selv for meg…før jeg begynte å tenke at tjaaaa, kanskje det kaaan være noe i det…til jeg innså at det er nøyaktig nerdete jeg er!

Jeg er usikker på om det blir nøyaktig en gang i uken, til fast tid – all den tid jeg tross alt ikke lever av å blogge, og har ca 100% jobb (som innimellom er en god del mer enn 100% også, faktisk) jeg skal gjennomføre, og som tross alt kommer før bloggen. Det regner jeg med alle forstår 😉

Uansett skal jeg forsøke å skrive om en av mine favorittformler en gang hver uke – jeg håper dere vil like det, og følge med!

Som den aller første ukens formel (jada, jeg kaller det ukens formel, selv om det kanskje ikke blir absolutt hver uke), gir jeg dere formelen for radiusen til en atomkjerne (*applaus*):

I denne formelen så kaller vi radiusen til atomkjernen til et eller annet atom for r. Hvor stor denne er avhenger av hvor mange nøytroner pluss hvor mange protoner det er i denne kjernen. Det er dette som kalles A - feks så er A for uran-233 rett og slett 233 (233 på slutten av en isotop forteller jo nettopp hvor mange partikler - protoner pluss nøytroner - eller nukleoner som er i denne kjernen). r0 er en konstant, og denne er alltid 1.25 femtometer (0.00000000000000125 meter). Det betyr at det eneste du trenger å vite for å finne radiusen til en eller annen atomkjerne er hvor mange partikler denne består av 🙂

Radiusen til uran-233 er dermed 1.25 ganget med tredjeroten av 233:

1.25*6.153 ≈ 7.7 femtometer.

Hvis vi heller lurer på radiusen til feks karbon-12 (det vanligste karbonet - det vi i hovedsak består av), så blir den:

1.25*2.29 ≈ 2.9 femtometer.

Størrelsen på en atomkjerne er altså femtometer-skala. Kjernefysikere holder dermed på med femtoteknologi - og femto er jo mye mindre enn nano, så da må det også være bedre...eller...? (Haha, jeg tuller 😉 )


Dette var den første ukens formel. Jeg har maaange på lager, men hvis du har et ønske så er det bare å si i fra, så ser jeg hva jeg kan få til ♥ God helg, alle! Selv har jeg lagt meg godt ned i sengen, og venter på Anders, som i skrivende stund befinner seg ca over Drammen (ja, jeg har fulgt med på flight radar siden klokken 8 i morgen tidlig, som var da Anders tok av fra LA #nerd 😉 ) - veldig snart er han her hjemme hos meg ♥

A normal misconception about nuclear physics is that it's all about nuclear power and/or atomic bombs, and that that's it. This is far from the truth, and therefore I think 10 facts about nuclear physics is a good idea today 🙂
  1. nuclear physics is  all about the atomic nucleus - discovered by accident by Ernest Rutherford a century ago, when he was bombarding a thin gold foil with alpha particles
  2. there's so much we don't know about the heart of the atom - the nucleus; and that's why we are a lot of people around the world still spending all of our lives to study it, and try to understand the nucleus and the nuclear force that holds it all together (how does it really work, and why, and how big can a nucleus actually get?)
  3. all atoms have a nucleus - nuclear physics is as much about the non-radioactive nuclei (stable gold, stable oxygen, stable iron), as the radioactive ones (thorium, uranium, plutonium) 
  4. the "applied part" of my phd thesis is about nuclear power, which is of course also one part of nuclear physics - how to produce energy from big nuclei that splits in two (you get heat and you can boil water and you get steam and then you can generate electricity)
  5. I don't want to lie; atomic bombs is also something that some people (not in Norway) study - knowledge about nuclear physics can be used in such a destructive way. As can most knowledge if I think of it...
  6. knowledge about nuclear physics tells us about the creation of the elements - what happens in the sun and similar stars; how do they get their energy, and what happens there? In stars like our sun, elements all the way up to iron are produced
  7. no elements that are heavier than iron can be produced in stars/the sun, but we know they exist  so they must have been created somehow (we know gold exist, we know thorium exist, we know there is lead - to give some examples), but not where they came from. Creation of these heavy elements is actually one of the great mysteries, and we think they are made in explosions or collisions in space. We use nuclear physics to try to figure out how and where all these elements are created.
  8. one of the really nice applications of nuclear physics is radiation therapy. Atomic radiation may cause cancer, but it may also cure cancer <3
  9. if you've ever had a CT scan, you've experienced applied nuclear physics. Think about it: it's kind of awesome that we can actually look inside the body, and get really great images of the inside, without even cutting it open...!
  10. PET, which is short for positron electron tomography is another imaging technique in the nuclear medicine, where you actually detect gamma radiation from an electron that meets its anti particle, the positron (awesome, seriously!). And from this you can create beautiful three dimensional images of for example a tumour inside the body

Nuclear physics is seriously awesome <3<3<3

Hi everyone, sorry I've been quiet since Sunday! I was planning to share my plan of the week on Monday, but then the day just sort of disappeared, and I really don't know what happened to the rest of the week either (I know that yesterday disappeared since I was in charge of the nuclear physics group's christmas party, and this weekend, including today, I'm at Trysil, but Monday, Tuesday, and Wednesday I really don't know...:/)
Anyway, here are 10 facts about Beta radiation, since today is Friday and it's rime for facts (read about Alpha radiation HERE):
  1. beta radiation consists of particles - you can call it betas, beta particles or beta radiation.
  2. beta particles (or betas or beta radiation) is just exactly the same as electrons - beta particles are free electrons.
  3. you can have either beta plus or beta minus radiation (so it's actually not exactly true that beta particles are electrons, because if they're beta plus particles, then they're positrons, and if they're beta minus, then they're electrons).
  4. I think beta decay (the process where a nucleus emits a beta particle) is really weird: I mean, a neutron actually changes into a proton (or a proton changes into a neutron, if it's a beta plus).
  5. beta minus decay is also called electron emission, and beta plus decay is called positron emission.
  6. when a nucleus emits (sends out) a beta particle, it transforms into a nucleus that has a higher proton number (hydrogen would for example turn into a helium nucleus, since helium has one more proton than hydrogen) - this also means, that, yes, you can make gold from platinum, that has one less proton than gold.
  7. beta particle a are sometimes relativistic - that means that they move with a speed that's close to the speed of light, and that makes them seriously difficult to deal with (for instance theoretical calculations).
  8. if the beta particle is emitted in air, it usually moves a few meters before it is stopped (it has a range of a couple of meters in air). In water it moves only a few centimeters. This means they're quite easy to shield yourself from...
  9. most fission products emit beta (minus) radiation.
  10. beta radiation can cause actual "burns" on your skin; you can see (and feel) that your skin turns red, if you're very close to an intense source of beat radiation.

This day started with fusion: at 07:55 I was at NRK, to be a guest at P13, Tidenes Morgen, to talk about fusion. Right after this I spent an hour on the phone, talking to a journalist in Vårt Land, about fusion (and what is sacred to me, and what I ask for forgiveness for, and such). The reason for this was, not surprisingly, the new fusion reactor in Germany - the Stellarator called Wendelstein 7-X, where they want to recreate what happens at the sun; you know, let tiny nuclei melt together to form heavier nuclei and energy at the same time (sort of the  holy grail of nuclear physics/energy).
Of course: before any of this, the sun rose, it was a beautiful morning, and I could see and feel the energy from fusion from our nearest star <3 To me, every day is fusion day 🙂
The rest of the day has been spent on my article... I started the seminar with a great talk/discussion with Sunniva Supervisor, and then the rest of the day has actually been quite good. There's still a lot of work to do, but I'm positive 🙂 Now I just have to make my self a deadline for the different parts remaining to be done in this article, and then I just have to keep those deadlines, and then I'm done - and can continue with article number three and four, and then the actual thesis, and then I'm done. Easy 😛
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I must say: I love <3 getting your snaps - cool assignments, workout and chemistry, preparing for talks about colliding dark matter - love love love it! I really want to answer all of you, so let me say I'm so sorry if I don't manage!
Now it's nighty night here at Soria Moria; tomorrow I'm going to work A LOT (at least 7 hours, according to my plan form Monday) on the article. Sleep tight everyone!

Today I've been preparing for a talk that i'll be giving tomorrow: it's for high school students that are visiting the University, and my title is 10 reasons why I love nuclear physics.


Well, the title I was given was 10 reasons why I like nuclear physics, but of course I had to change the like into a love; I guess with me there's no in between - I either love something, or I hate it, and I love nuclear physics <3
  1. the idea of the atom is really a philosophical and "simple" idea
  2. the atom is more or less all empty space
  3. the nuclear force is the strongest one we know of - when we release it, fascinating (and scary) things can happen
  4. things are strange: mass can become energy, and energy can become mass (Einstein, Einstein, Einstein)
  5. nuclear power is environmental friendly: 1.053 grams of uranium-235 that all fission release the same amount of energy as if you burn 4 tons of coal
  6. nuclear power is the safest way (of all) of producing power, but interestingly that isn't the common perception
  7. it's all kind of mysterious - the nucleus radiates, and there's a lot of fear around this, but all in all it's "just" energy 🙂
  8. knowledge that can be used to produce weapons of mass destruction can also be used to cure cancer <3
  9. it's still sooo much we don't understand; 100 years after Rutherford discovered the atomic nucleus, we are still doing extremely similar experiments
  10. the study of (some of) the smallest things (the nucleus) is suddenly the same as studying the biggest things (big explosions in space)
I have to get up super early tomorrow morning, to finish my slides, so I think I'll just say good night, and sleep tight <3<3<3

2

Today I just wanted to tell you a little bit about neutrons, and why I think they're the coolest. You know, in a way they're like a Chanel purse - classical, and never out of style 😉
speaking of Chanel: I've been thinking that I should buy a black Chanel purse as a gift for my self when I have finished my PhD, but maybe I should consider the pink one instead...?
So here are my ten reasons why I think neutrons are really cool:
  1. Neutrons have no charge
  2. They decide if an atom is stable or radioactive
  3. A single neutron can sneak its way into a nucleus and make fission <3
  4. It's an unstable particle with a half life of a little bit more than 10 minutes
  5. I sort of envision them as white dots, or tiny billiard balls...
  6. A free neutron turns into hydrogen (meaning that the neutron is actually a radioactive particle - radioactivity is just soooo fascinating 😀 )
  7. Neutrons are the "flame" in the fuel of a nuclear reactor
  8. Neutrons gives different doses (of radiation) depending on their  energy 
  9. You can make a neutron from a proton and a proton from a neutron (almost sounds like witchcraft, or something)
  10. If neutrons have the right energy, they can do quite a lot of damage - but you can just use normal water as a shield, and you're fine 😉
I just love them - neutrons are without doubt my favorite. They're fabulous ✨

Do you have a favorite particle?

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PS: I am working on Question of the month (which is actually not a nuclear physics one this first time) - the plan was to publish it yesterday, but since I (unfortunately? 😛 ) have another job than just being a blogger, I haven't been able to finish it yet , and I'm really sorry :/ However, I'm still inside my own "limits", since I said it would come this week, and even though it's Friday, it's not the end of the week just yet 😉

8

 

Today I was part of the "panel of scientists" on Abels Tårn - the radio show that airs on Friday mornings at NRK P2 (this particular show will not air until December; probably December 4th). This time was sort of a "special edition", where the audience were all high school students (and their teachers), and all the questions were from these students.
So far, so good: GREAT FUN! (For the first time, I was on the show together with Anders - that didn't make it any less fun <3 )
After the show, one teacher came up to me (at least I think tha's what she was), and told me she had two questions. 
Great, I thought...
But  they weren't questions, they were more like "questions":
The first one was if a Molten Salt Reactor will release less radioactivity during normal operation than today's reactors, and the second one I'm not sure if she ever asked; except she was asking me about all these Germans that had written stuff in German, and I said (several times - at first I was polite) that I don't speak German, so, no, I have not read these things (but I should, according to her). She was laughing in my face when I said that there are no radioactive releases during normal operation of reactors even today (and of course not in the future), and just told me I was wrong (and said that if I just read these German things I would know that I was wrong...). Still I didn't just leave (that would be rude), I tried to talk about radiation doses and limits - it wasn't very successful.

This teacher pretended to have questions, but was not interested in listening to what I said, and just went on and on and on about new German titles that I should (have) read. It was annoying and rude, and I'm still kind of upset, actually :/

all photos: Yngve Vogt

Maybe the worst part is that this teacher (if that's what she was) was stealing time from the students that had several questions for me, and that I would really have wanted to talk to - not to tell them so much about nuclear physics, but about science, and research, and all the amazing possibilities...
BTW: Thank you so much to the student who just wanted to tell me that she really enjoyed my TEDxOslo talk <3 The talk from LeRosey, last year, is HERE, and the one from Bergen, a couple of weeks ago will come very soon (stay tuned).
PS: It's TOTALLY OK to disagree with my view on nuclear power, but please don't pretend to ask me questions when you have no intensions of listening to what I say, and not respect me as a scientist. I try very hard not to pretend to be an "expert" on stuff taht I'm not working on, so don't pretend that I know nothing about my own f*****g field of science. Thank you <3 
PPS: Besides the behavior of this teacher, it was a great day, and I had a lot of fun being part of Abels Tårn today!

2

One thing that is kind of funny is that in Norwegian the word for "nuclear force" and "nuclear power" is the same - "kjernekraft".
It's the same word that describes the force that holds the atomic nucleus together and the way of producing power by splitting atoms. So in Norwegian you just can't be against kjernekraft, because it makes no sense: If you're against kjernekraft you're against atomic nuclei, and basically more or less everything, since there is nothing bigger than elementary particles - there wouldn't even be bigger particles like protons or neutrons, since they are made up from quarks that need kjernekraft to exist...
(PS: Of course I'm not really that pedantic - I do understand what people mean when they say they're against kjernekraft. But as I've said earlier, I actually don't understand how it is possible to worry about climate change, and not be pro nuclear, so I guess in a way I'll still say it makes little sense to be against kjernekraft 😉 )

no flowers, no sun, no sunset without kjernekraft...

#thinkaboutthat
#tenklittpådet