Radiation astronomy/Transmutations

From Wikiversity
Jump to navigation Jump to search
This graph shows positron emissions, among others, from nuclear transmutation. Credit: Napy1kenobi.

If the proton and neutron are part of an atomic nucleus, these decay processes transmute one chemical element into another. For example:

where A = 22, Z = 11, N = Na, Z-1 = 10, and N' = Ne.

Beta decay does not change the number of nucleons, A, in the nucleus but changes only its charge, Z. Thus the set of all nuclides with the same A can be introduced; these isobaric nuclides may turn into each other via beta decay. Among them, several nuclides (at least one) are beta stable, because they present local minima of the mass excess: if such a nucleus has (A, Z) numbers, the neighbour nuclei (A, Z−1) and (A, Z+1) have higher mass excess and can beta decay into (A, Z), but not vice versa. For all odd mass numbers A the global minimum is also the unique local minimum. For even A, there are up to three different beta-stable isobars experimentally known. There are about 355 known beta-decay stable nuclides total.

Radioactive decay[edit | edit source]

This is a fission reaction. Credit: Pearson Scott Foresman.

Sometimes elements are unstable, and they decay into more stable elements. Some do this slowly, in a matter of thousand, millions or even billions of years, while others do it quickly, sometimes in a matter of milliseconds. Any radioactive isotope has a half life, that is how long it will take half of a certain amount of radioactive material to decay into a different isotope. For instance, Uranium-234 has a half life of 245,000 years,[1] so after 245,000 years a 1-gram sample of Uranium-234 would have only 1/2 gram of Uranium-234 in it. For this isotope, every 245,000 the amount of Uranium-243 in a sample is cut in half. So after 490,000 years, 1/4 of a grams of Uranium-234 will remain in the sample. Different isotopes of different elements generally have different half-lifes. For instance, Polonium-214 has a half life of 163 microseconds (a microsecond is one-millionth of a second). [2] When this process is started artificially, it is called transmutation. [3]

This is an example of an artificial transmutation, this one being called a fission reaction:

Transmutation of species[edit | edit source]

This image is of an internal mold for Laevitrigonia gibbosa from the Portland Limestone Formation (Upper Jurassic), Isle of Portland, Dorset, England. Credit: Photograph taken by Mark A. Wilson (Department of Geology, The College of Wooster).

Def. the process of changing, transforming or converting one species into another, or from one species into another, is called transmutation of species.

In the early 19th century, Jean-Baptiste Lamarck proposed his theory of the transmutation of species, the first fully formed theory of evolution.

"Lamarck became convinced of the transmutation of species during the period 1797-1800 ... He used Trigonia as a prime example of a once-dominant group [in the Mesozoic] which had been drastically restricted in diversity, abundance, and geographic range"[4] down to one genus Neotrigonia and five living species. All are found off the coast of Australia.

Hypotheses[edit | edit source]

  1. The use of satellites should provide ten times the information as sounding rockets or balloons.

A control group for a radiation satellite would contain

  1. a radiation astronomy telescope,
  2. a two-way communication system,
  3. a positional locator,
  4. an orientation propulsion system, and
  5. power supplies and energy sources for all components.

A control group for radiation astronomy satellites may include an ideal or rigorously stable orbit so that the satellite observes the radiation at or to a much higher resolution than an Earth-based ground-level observatory is capable of.

See also[edit | edit source]

References[edit | edit source]

External links[edit | edit source]

{{Radiation astronomy resources}}{{Repellor vehicle}}