Most values listed in this factsheet are from the following sources:
NASA Goddard Space Flight Center
IAU/IAG Working Group Report, 2006
Astronomical Almanac, 2000, 2001
Global Earth Physics, American Geophysical Union, 1995
Astrophysical Quantities, C.W. Allen, 1981, 2000
Recent journal articles and personal communications

Note that the values listed on the factsheet are not “official” values,
there is no single set of agreed upon values. They are based on ongoing
research and as such are under study and subject to change at any time.
Every effort has been made to present the most up-to-date information,
but care should be exercised when using these values.