ANS is committed to advancing, fostering, and promoting the development and application of nuclear sciences and technologies to benefit society.
Explore the many uses for nuclear science and its impact on energy, the environment, healthcare, food, and more.
Division Spotlight
Robotics & Remote Systems
The Mission of the Robotics and Remote Systems Division is to promote the development and application of immersive simulation, robotics, and remote systems for hazardous environments for the purpose of reducing hazardous exposure to individuals, reducing environmental hazards and reducing the cost of performing work.
Meeting Spotlight
2024 ANS Annual Conference
June 16–19, 2024
Las Vegas, NV|Mandalay Bay Resort and Casino
Standards Program
The Standards Committee is responsible for the development and maintenance of voluntary consensus standards that address the design, analysis, and operation of components, systems, and facilities related to the application of nuclear science and technology. Find out What’s New, check out the Standards Store, or Get Involved today!
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Nuclear Science and Engineering
June 2024
Nuclear Technology
May 2024
Fusion Science and Technology
Latest News
Commercial nuclear innovation "new space" age
In early 2006, a start-up company launched a small rocket from a tiny island in the Pacific. It exploded, showering the island with debris. A year later, a second launch attempt sent a rocket to space but failed to make orbit, burning up in the atmosphere. Another year brought a third attempt—and a third failure. The following month, in September 2008, the company used the last of its funds to launch a fourth rocket. It reached orbit, making history as the first privately funded liquid-fueled rocket to do so.
Nuclear science is far-reaching in the fabric of modern life. It can help explain the origins of the universe or how x-rays reveal the bones in your body. In fact, nuclear science is at the heart of so many of the technologies that improve our lives, that it’s easy to take for granted how those technologies came to be. But behind every innovation and discovery in the nuclear fields, is a scientist or engineer researching the atomic nucleus and how to use it to improve our lives.
Scientists used to think there was nothing smaller than an atom.
Today, we know the atom is made of smaller particles, and those are made of even smaller particles.
The nucleus is made of protons and neutrons; each has the same mass: 1 amu (atomic mass unit).
Protons and neutrons aren’t exactly alike, though; protons have a positive charge while neutrons don’t have a charge.
Electrons are so small that they have nearly no mass at all. A single electron has only 1/1836 amu. Electrons are also negatively charged.
All of the known elements are organized on the periodic table of the elements. They are arranged by atomic number, from smallest to largest, and labeled with their element symbol, atomic number, and atomic mass.
To easily communicate information about the elements, scientists use standard nuclear notation.
Nuclear notation is formed by writing an elemental symbol with a number above indicating its atomic number—the number of protons—and a number below indicating its mass number—the number of protons and neutrons combined.
For example: Carbon has 6 protons, so it’s atomic number is 6.
Carbon's mass number is 12. How many neutrons does it have?
The mass number of an element is a round number; the atomic mass usually isn't. Atomic mass is an average mass of all of the isotopes of an element. We use the mass number, which is always a round number, to make calculations easier.
Think about clover. Clovers can have three, four, or even more leaves. The four-leaved clovers are rare, but they are still clovers. In a similar way, two atoms of an element can have different numbers of neutrons. Because they still have the same number of protons, though, they are the same element. These “varieties” of the same element are called isotopes.
Learn more about radioactivity
Last modified June 20, 2022, 9:42am CDT