The total number of protons and neutrons in an atom's nucleus. For example, oxygen-16 has a mass number of sixteen, because it has eight protons and eight neutrons.
The amount of matter in a body, which should not be confused with weight. The same object will have different weights in space and earth but the mass remains constant.
Mass is a measure of the tendency of an object to resist acceleration. It's harder to roll a tractor trailer than a roller skate; the tractor trailer has a far greater mass.
The Eucharist or principal sacramental celebration of the Church, established by Jesus at the Last Supper, in which the mystery of our salvation through participation in the ...
One of about a dozen of the strongest Fraunhofer lines seen in the Solar spectrum, the A band at 7600 angstoms is due to telluric lines of molecular oxygen in the Earth's ...
Star with spectral type A in which the spectrum of the Balmer lines of hydrogen attain their greatest strength. Helium lines can no longer be seen. Some metallic lines are ...
1) Angular distance from the north point eastward to the intersection of the celestial horizon with the vertical circle passing through the object and the zenith.
2) Directional ...
A disaster which occurred in the Chernobyl power plant in 1986, where one out of four nuclear reactors in the plant exploded, resulting in at least 5% ...
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