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
Human Factors, Instrumentation & Controls
Improving task performance, system reliability, system and personnel safety, efficiency, and effectiveness are the division's main objectives. Its major areas of interest include task design, procedures, training, instrument and control layout and placement, stress control, anthropometrics, psychological input, and motivation.
Meeting Spotlight
Conference on Nuclear Training and Education: A Biennial International Forum (CONTE 2025)
February 3–6, 2025
Amelia Island, FL|Omni Amelia Island Resort
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!
Latest Magazine Issues
Dec 2024
Jul 2024
Latest Journal Issues
Nuclear Science and Engineering
December 2024
Nuclear Technology
Fusion Science and Technology
November 2024
Latest News
World Nuclear Energy Day grows in recognition
Since its inception in 2020, World Nuclear Energy Day has grown in awareness each year. The day is celebrated annually on December 2.
This year on December 2, the U.S. Senate passed a resolution for World Nuclear Energy Day, celebrating the peaceful development of nuclear energy technology and underscoring the vital role of nuclear power in strengthening the U.S. economy and supporting a reliable energy grid worldwide.
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