nuclearvault:

Starfish Prime was a high-altitude nuclear test conducted by the United States on 9 July 1962 as part of Operation Fishbowl over Johnston Atoll. It was successfully detonated at an altitude of 400 km (250 mi) at 09:00:09 Honolulu time.

Starfish Prime’s electromagnetic pulse was much larger than originally expected and drove much of the instrumentation off scale, as well as causing electrical damage in Hawaii, which was about 1,445 km (898 mi) away from the detonation point. It knocked out about 300 streetlights, set off numerous burglar alarms and damaged a telephone company microwave link. 

I like this, but before anyone gets on the ‘EMP=end of the world’ train please see: 
http://lewis.armscontrolwonk.com/archive/4293/talking-warheads-on-emp

http://lewis.armscontrolwonk.com/archive/6626/more-emp-nonsense

jtotheizzoe:

spaceplasma:

xysciences:

A gif representing nuclear fusion and how it creates energy. 
[Click for more interesting science facts and gifs]

For those who don’t understand the GIF. It illustrates the Deuterium-Tritium fusion; a deuterium and tritium combine to form a helium-4. Most of the energy released is in the form of the high-energy neutron.
Nuclear fusion has the potential to generate power without the radioactive waste of nuclear fission (energy from splitting heavy atoms  into smaller atoms), but that depends on which atoms you decide to fuse. Hydrogen has three naturally occurring isotopes, sometimes denoted ¹H, ²H, and ³H. Deuterium (²H) - Tritium (³H) fusion (pictured above) appears to be the best and most effective way to produce energy. Atoms that have the same number of protons, but different numbers of neutrons are called isotopes (adding a proton makes a new element, but adding a neutron makes an isotope of the same atom). 
The three most stable isotopes of hydrogen: protium (no neutrons, just one proton, hence the name), deuterium (deuterium comes from the Greek word deuteros, which means “second”, this is in reference two the two particles, a proton and a neutron), and tritium (the name of this comes from the Greek word “tritos” meaning “third”, because guess what, it contains one proton and two neutrons). Here’s a diagram
Deuterium is abundant, it can be extracted from seawater, but tritium is a  radioactive isotope and must be either derived(bred) from lithium or obtained in the operation of the deuterium cycle. Tritium is also produced naturally in the upper atmosphere when cosmic rays strike nitrogen molecules in the air, but that’s extremely rare. It’s also a by product in reactors producing electricity (Fukushima Daiichi Nuclear Power Plant). Tritium is a low energy beta emitter (unable to penetrate the outer dead layer of human skin), it has a relatively long half life and short biological half life. It is not dangerous externally, however emissions from inhaled or ingested beta particle emitters pose a significant health risk.
During fusion (energy from combining light elements to form heavier ones), two atomic nuclei of the hydrogen isotopes deuterium and tritium must be brought so close together that they fuse in spite of the strongly repulsive electrostatic forces between the positively charged nuclei. So, in order to accomplish nuclear fusion, the two nuclei must first overcome the electric repulsion (coulomb barrier ) to get close enough for the attractive nuclear strong force (force that binds protons and neutrons together in atomic nuclei) to take over to fuse the particles. The D-T reaction is the easiest to bring about, it has the lowest energy requirement compared to energy release. The reaction products are helium-4 (the helium isotope) – also called the alpha particle, which carries 1/5 (3.5 MeV) of the total fusion energy in the form of kinetic energy, and a neutron, which carries 4/5 (14.1 MeV). Don’t be alarmed by the alpha particle, the particles are not dangerous in themselves, it is only because of the high speeds at which they are ejected from the nuclei that make them dangerous, but unlike beta or gamma radiation, they are stopped by a piece of paper.

Some fundamentals of fusion.

jtotheizzoe:

spaceplasma:

xysciences:

A gif representing nuclear fusion and how it creates energy. 

[Click for more interesting science facts and gifs]

For those who don’t understand the GIF. It illustrates the Deuterium-Tritium fusion; a deuterium and tritium combine to form a helium-4. Most of the energy released is in the form of the high-energy neutron.

Nuclear fusion has the potential to generate power without the radioactive waste of nuclear fission (energy from splitting heavy atoms  into smaller atoms), but that depends on which atoms you decide to fuse. Hydrogen has three naturally occurring isotopes, sometimes denoted ¹H, ²H, and ³H. Deuterium (²H) - Tritium (³H) fusion (pictured above) appears to be the best and most effective way to produce energy. Atoms that have the same number of protons, but different numbers of neutrons are called isotopes (adding a proton makes a new element, but adding a neutron makes an isotope of the same atom). 

The three most stable isotopes of hydrogen: protium (no neutrons, just one proton, hence the name), deuterium (deuterium comes from the Greek word deuteros, which means “second”, this is in reference two the two particles, a proton and a neutron), and tritium (the name of this comes from the Greek word “tritos” meaning “third”, because guess what, it contains one proton and two neutrons). Here’s a diagram

Deuterium is abundant, it can be extracted from seawater, but tritium is a  radioactive isotope and must be either derived(bred) from lithium or obtained in the operation of the deuterium cycle. Tritium is also produced naturally in the upper atmosphere when cosmic rays strike nitrogen molecules in the air, but that’s extremely rare. It’s also a by product in reactors producing electricity (Fukushima Daiichi Nuclear Power Plant). Tritium is a low energy beta emitter (unable to penetrate the outer dead layer of human skin), it has a relatively long half life and short biological half life. It is not dangerous externally, however emissions from inhaled or ingested beta particle emitters pose a significant health risk.

During fusion (energy from combining light elements to form heavier ones), two atomic nuclei of the hydrogen isotopes deuterium and tritium must be brought so close together that they fuse in spite of the strongly repulsive electrostatic forces between the positively charged nuclei. So, in order to accomplish nuclear fusion, the two nuclei must first overcome the electric repulsion (coulomb barrier ) to get close enough for the attractive nuclear strong force (force that binds protons and neutrons together in atomic nuclei) to take over to fuse the particles. The D-T reaction is the easiest to bring about, it has the lowest energy requirement compared to energy release. The reaction products are helium-4 (the helium isotope) – also called the alpha particle, which carries 1/5 (3.5 MeV) of the total fusion energy in the form of kinetic energy, and a neutron, which carries 4/5 (14.1 MeV). Don’t be alarmed by the alpha particle, the particles are not dangerous in themselves, it is only because of the high speeds at which they are ejected from the nuclei that make them dangerous, but unlike beta or gamma radiation, they are stopped by a piece of paper.

Some fundamentals of fusion.

A bomb without Einstein?

Fermi’s work came directly out of an experimentalist, nuclear physics context where physicists were bombarding substances with all manner of subatomic particles to see what happened.”

I love that. 

I Left Academia Because I Didn't Think It Was Worth All The Trouble -- Apparently Other Women Feel The Same

thatssoscience:

One of the most honest descriptions of leaving academia. I loved this paragraph :

 ”But I can’t tell you how many times I’ve heard “Oh, you think I’m bad? You should see how my Professor treated me! I’m nice!” as if that excuses any behavioral transgression. It’s a vicious, stupid, self-perpetuating cycle that reduces scientific research to some sort of hazing ritual. And, once your tenured, you can really start being a dick in earnest, because why be nice if there are no repercussions to being mean?”

 

Let’s bring some humanity back to the sciences. 

(via scinerds)

"What is Alpha, Beta, and Gamma Radiation?"
-

Alpha radiation is high-energy electrons or positrons, two protons and two neutrons sticking together with no electrons around. Very potent, but penetrates matter weakly. A sheet of paper (or your skin) will block them. When alpha-active matter is ingested it will cause major problems.

Beta radiation is high-energy electrons. Similarly to Alpha radiation, both are made of particles and penetrate matter weakly. Beta radiation can be blocked by a thin sheet of metal.

Gamma radiation is extremely high frequency photons, beyond UV and X-rays. It penetrates matter easily and you need excessive lead shielding to filter out a lethal dose.

/u/menolith

(via sdsimple)