Neptunium-239 | chemical isotope (2024)

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Why do heavy objects tend to fall downwards when dropped? How are birds able to fly (and why can’t I do the same?)? Human beings have long been curious about the world in which we live, striving to identify connections among the phenomenons we witness and to understand how it all works. The field of science has developed over many centuries as a way of studying and understanding the world, beginning with the primitive stage of simply noting important regularities in nature and continuing through the rise of modern science. The modern-day sciences cover a vast range of fields, including biology, chemistry, meteorology, astronomy, physics, and much more.","image":{"id":0,"url":"/86/193986-050-7B2DBB6A/ball-and-stick-model-structure-atoms.jpg","altText":"Science","credit":null,"width":null,"height":null,"fullUrl":"https://cdn.britannica.com/86/193986-050-7B2DBB6A/ball-and-stick-model-structure-atoms.jpg"}},{"id":1000,"title":"Science","url":"Science","description":"How can the sky be blue one day and stormy the next? Why do heavy objects tend to fall downwards when dropped? How are birds able to fly (and why can’t I do the same?)? Human beings have long been curious about the world in which we live, striving to identify connections among the phenomenons we witness and to understand how it all works. The field of science has developed over many centuries as a way of studying and understanding the world, beginning with the primitive stage of simply noting important regularities in nature and continuing through the rise of modern science. The modern-day sciences cover a vast range of fields, including biology, chemistry, meteorology, astronomy, physics, and much more.","image":{"id":0,"url":"/86/193986-050-7B2DBB6A/ball-and-stick-model-structure-atoms.jpg","altText":"Science","credit":null,"width":null,"height":null,"fullUrl":"https://cdn.britannica.com/86/193986-050-7B2DBB6A/ball-and-stick-model-structure-atoms.jpg"}},null],"mainCategory":{"id":1000,"title":"Science","url":"Science","description":"How can the sky be blue one day and stormy the next? Why do heavy objects tend to fall downwards when dropped? How are birds able to fly (and why can’t I do the same?)? Human beings have long been curious about the world in which we live, striving to identify connections among the phenomenons we witness and to understand how it all works. The field of science has developed over many centuries as a way of studying and understanding the world, beginning with the primitive stage of simply noting important regularities in nature and continuing through the rise of modern science. The modern-day sciences cover a vast range of fields, including biology, chemistry, meteorology, astronomy, physics, and much more.","image":{"id":0,"url":"/86/193986-050-7B2DBB6A/ball-and-stick-model-structure-atoms.jpg","altText":"Science","credit":null,"width":null,"height":null,"fullUrl":"https://cdn.britannica.com/86/193986-050-7B2DBB6A/ball-and-stick-model-structure-atoms.jpg"}},"typeDisplayName":"Demystified"}]},"byline":null,"citationInfo":null,"websites":null,"freeTopicReason":"COUNTRY_IS_FREE","articleSchemaMarkup":{"keywords":"neptunium-239","wordcount":0,"url":"https://www.britannica.com/science/neptunium-239","description":"Other articles where neptunium-239 is discussed: uranium processing: Conversion to plutonium: Neptunium-239 in turn undergoes beta decay, being transformed into plutonium-239 (atomic number 94).","publisher":{"name":"Encyclopedia Britannica","@type":"Organization","logo":{"url":"https://corporate.britannica.com/wp-content/themes/eb-corporate/_img/logo.png","@type":"ImageObject"}},"@context":"https://schema.org","@type":"article"},"studentArticle":false,"initialLoad":true}