Astrophysics (index)


(element, Ca, atomic number 20)

Calcium is an element, atomic number 20, symbol Ca. Usual isotope has atomic weight 40, but 42, 43, and 44 are more stable and 46 is stable as well.

Fifth most common element in the Earth's crust.

The Sun has strong Absorption Lines of singly ionize calcium (Ca II), H line (396.85 nm) and K line (393.37 nm).


Referenced by:
Calcium-rich Gap Transient
Carbonate-Silicate Cycle
Type Ia Supernova