The number of protons in an atomic nucleus . The atomic number and the element symbol are two alternate ways to label an element. In nuclide symbols , the atomic number is a ...
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 ...
Also known as All Hallow's Eve, Halloween is an annual holiday celebrated on October 31st in America, Canada, and the UK. It is supposedly the one day ...
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