(via Urban Walking by HR-FM on deviantART)
@1 month ago with 53 notes


"In the spring of 1955, as the Cold War intensified and the arms race between the United States and the Soviet Union escalated at a shocking pace, America — as it had many times before — detonated an atomic weapon in the Nevada desert. The test was not especially noteworthy. The weapon’s yield was not dramatically larger or smaller than that of previous A-bombs. The brighter-than-the-sun flash of light, the mushroom cloud and the staggering power unleashed by the weapon were all byproducts familiar to anyone who had either witnessed or paid attention to coverage of earlier tests.

And yet today, six decades later, at a time when the prospect of nuclear tests by “rogue states” like North Korea and Iran is once again making headlines and driving international negotiations and debate, the very banality of one long-forgotten atomic test in 1955 feels somehow more chilling than other more memorable or era-defining episodes from the Cold War. After all, whether conducted in the name of deterrence, defense or pure scientific research, the May 1955 blast was in a very real sense routine.

This is not to suggest that the scientists, engineers and other professionals involved at Yucca Flat were somehow cavalier about detonating atomic weapons. But it’s worth remembering that, in the first half of 1955, the U.S. conducted more than a dozen nuclear test explosions in Nevada alone. After a while, the mushroom clouds from these tests, visible from Las Vegas 60 miles away, had become tourist draws. One needn’t be a pacifist, an anti-nuclear crusader or a modern-day Luddite to shudder at the thought of nuclear explosion after nuclear explosion after nuclear explosion — and the lethal aftermath of what such explosions entail — ripping through the dry desert air of the starkly gorgeous American southwest.

Made in the Nevada desert by photographer Loomis Dean shortly after a 1955 atomic bomb test, these are not “political” pictures. They are eerily beautiful, unsettling photographs made at the height of the Cold War, when the destructive power of the detonation was jaw-droppingly huge — but positively miniscule compared to today’s truly terrifying thermonuclear weapons. As LIFE told its readers in its 16 May 1955 issue:

A day after the 44th nuclear test explosion in the U.S. rent the still Nevada air, observers cautiously inspected department store mannequins which were poised disheveled but still haughty on the sand sand in the homes of Yucca Flat. The figures were residents of an entire million-dollar village built to test the effects of an atomic blast on everything from houses to clothes to canned soup.

The condition of the figures — one charred, another only scorched, another almost untouched — showed that the blast, equivalent to 35,00 tons of TNT, was discriminating in its effects. As one phase of the atomic test, the village and figures help guide civil defense planning — and make clear that even amid atomic holocaust careful planning could save lives.

There is, in such words and in such sentiments, an almost unrecognizable optimism  it’s tempting to say, an innocence that is no longer available to us when it comes to honest discussions of, as LIFE put it, “atomic holocaust.” With conversations about nuclear tests (both theoretical and real) so very much in the news these days, these pictures from more than half a century ago might serve as a quiet reminder of just how horrific and insane the very notion of nuclear warfare really is.”

[Nevada Ghosts: LIFE at an A-Bomb Test, 1955]

@9 months ago with 69 notes

Inside the nursery school. #chernobyl #Ukraine #nuclear #power #station #disaster #radiation #geiger #gamma #exclusion #abandoned #deserted #evacuated #ussr #soviet #tour #visit #trip #kiev


Inside the nursery school. #chernobyl #Ukraine #nuclear #power #station #disaster #radiation #geiger #gamma #exclusion #abandoned #deserted #evacuated #ussr #soviet #tour #visit #trip #kiev

@11 months ago with 4 notes

Inside the nursery school. #chernobyl #Ukraine #nuclear #power #station #disaster #radiation #geiger #gamma #exclusion #abandoned #deserted #evacuated #ussr #soviet #tour #visit #trip #kiev


Inside the nursery school. #chernobyl #Ukraine #nuclear #power #station #disaster #radiation #geiger #gamma #exclusion #abandoned #deserted #evacuated #ussr #soviet #tour #visit #trip #kiev

@11 months ago with 3 notes
@11 months ago with 25 notes


NUTEX Radium Condoms (ca. 1940s)

@11 months ago with 66 notes


Understanding Chernobyl: Positive Void Coefficent (or void coefficient of reactivity)

A void coefficient allows operators to estimate how much the reactivity of a nuclear reactor will change as voids (typically steam bubbles) form in the coolant and moderator.

A positive void coefficient means reactivity in a reactor increases as more voids are created. The RBMK design had a dangerously high positive coefficient. Light water was used as coolant and graphite for moderation. Because the light water was boiling, more steam voids were forming. Steam voids don’t absorb neutrons, leaving them to collide with uranium, which then leads to more heat. More heat means more steam voids will form in the reactor and increase reactivity.


1. Light water is boiling inside the reactor.
2. Because the water is boiling, more steam voids are forming and coolant is being lost.
3. Without coolant, the temperature in the reactor increases exponentially, creating a massive amount of heat.
4. The increase of temperature boils more water and more steam voids form.
5. Even more coolant is lost, allowing more neutrons to fission with uranium-235, which pushes reactivity even higher. The reactor is now embarking on a positive feedback loop because of its high positive void coefficient.
6. Rinse and repeat.

@11 months ago with 39 notes


Greenpeace says…

1. “Nuclear weapons are the same as nuclear power reactors.”

There are 2 types of nuclear weapons: atomic and thermonuclear.

Atomic weapons assemble a supercritical mass of uranium with an uncontrolled rate of fission. In order to accomplish such a rate, uranium-235 needs to be enriched to at least 90%. This is far beyond that of natural uranium. Reactor fuel is a combination of uranium-235 enriched to around 5% and uranium-238 makes up the rest of the fuel. This makes using spent fuel in nuclear weapons with a favorable outcome is nearly impossible.

Thermonuclear weapons use both fission and fusion in the same weapon. Obviously, nuclear fusion is an underdeveloped technology, making thermonuclear weapons and nuclear reactors very, very different.

That being said, the rate of reactivity in a reactor is controlled by its moderator and coolant, as well as several control and safety rods that are lowered into the reactor core automatically if any deviation from normal operating conditions occur. These rods can slow the reactor’s chain reaction down significantly or can stop it all together. Once a reaction in a nuclear weapon has started, there’s no going back. These explosions occur within a matter of seconds. Chernobyl’s meltdown has often been used as “proof” that nuclear reactors can explode like nuclear weapons, but explosions in the reactor were the product of a deadly combination of nuclear fuel (soaring temperatures caused fuel claddings to rupture) and coolant, causing the water to violently flash to steam. Even then, this is not a fault of nuclear fission itself.


1. For an atomic weapon to detonate successfully, uranium-235 needs to be enriched to at least 90%. Uranium-235 is fissile, meaning it can sustain a chain reaction.

2. Most nuclear fuel is composed of uranium-235 that is enriched to at most 5% and uranium-238 makes up the rest of it. When the uranium-235 has been depleted, the fuel is no longer usable because only uranium-238 remains. Uranium-238 is fertile (can be fissioned by fast neutrons) but is not fissile (cannot sustain a chain reaction).

3. An uncontrollable nuclear reaction is required for a nuclear weapon to detonate. The rate of fission in nuclear reactors is constantly monitored and controlled with a moderator and control/safety rods. A runaway chain reaction in a reactor isn’t likely to occur unless a loss of coolant accident takes place.

@11 months ago with 23 notes


Nicholas Ballesteros.

From Selected Collage 2014


@7 months ago with 865 notes


Byron Nuclear Generating Station (Exelon)
Byron, Illinois

@9 months ago with 28 notes

(Source: ehcsu)

@11 months ago with 8 notes
@11 months ago with 19 notes

(Source: nuclearvault)

@11 months ago with 28 notes

(Source: nuclearvault)

@11 months ago with 14 notes


Pripyat Evacuation Broadcast - 27 April 1986, 14:00

The city of nearby Pripyat was not immediately evacuated following Reactor #4’s meltdown at Chernobyl. Completely oblivious to what had just happened, the townspeople went about their usual business. Symptoms indicating acute radiation poisoning became apparently only a few hours after the explosion. Dozens of people were reporting severe headaches and metallic tastes in their mouths, along with uncontrollable fits of coughing and vomiting. A commission set up by the state was formed and confirmed that extremely high levels of radiation had caused a number of cases of radiation exposure and ordered the city of Pripyat to be evacuated.

For the attention of the residents of Pripyat! The City Council informs you that, due to the accident at Chernobyl Power Station in the city of Pripyat, the radioactive conditions in the vicinity are deteriorating. The Communist Party, its officials, and the armed forces are taking necessary steps to combat this. Nevertheless, with the view to keep people as safe and healthy as possible, the children being top priority, we need to temporarily evacuate the citizens in the nearest towns of Kiev Oblast. For these reasons, starting at 14:00 on 27 April, each apartment block will be able to have a bus at its disposal, supervised by the police and city officials. It is highly advisable to take your documents, vital personal belongings, and a certain amount of food, just in case, with you. The senior executives of public and industrial facilities of the city have decided on the list of employees needed to stay in Pripyat to maintain these facilities in good working order. All houses will be guarded by the police during the evacuation period. Comrades, leaving your residences temporarily, please make sure you have turned off the lights, electrical equipment, and water, and shut the windows. Please keep calm and orderly in the process of this short-term evacuation.

Officials instructed residents only to bring what was absolutely necessary as the evacuation period would only be in effect for 3 days. Slowly, the gravity of the situation was being pieced together by officials and the evacuation order was extended indefinitely. 

@11 months ago with 32 notes