{"lower":0.00007,"year":1760,"source":"Buffon. time of cooling from molten state. Earth"}
{"lower":0.24,"year":1831,"source":"Lyell. age of mollusks. Earth"}
{"lower":1,"upper":10,"year":1852,"source":"Bok. galactic clusters"}
{"lower":0.02,"year":1897,"source":"Thomson. Thermodynamics of earth. Min is between 20-400million"}
{"lower":2,"year":1929,"source":"E. Hubble. Redshift"}
{"lower":10,"upper":15,"year":1970,"source":"various"}
{"lower":16,"upper":20,"year":1980,"source":"various"}
{"lower":12.07,"year":1996,"source":"Chaboyer"}
{"lower":10,"year":1997,"source":"Krauss"}
{"lower":12,"year":1999,"source":"Hubble telescope. Hubble constant"}
{"lower":11,"upper":20.2,"year":1999,"source":"Cowan "}
{"lower":9.5,"upper":15.5,"year":2001,"source":"Cayrel"}
{"lower":13,"upper":14,"year":2002,"source":"Hubble telescope"}
{"lower":11.2,"upper":20,"year":2003,"source":"Krauss, Chaboyer, Science, 2003"}
{"lower":13.56,"upper":13.84,"year":2003,"source":"WMAP satellite. Microwave radiation"}
{"lower":13.713,"upper":13.831,"year":2013,"source":"Nine-Year Wilkinson Microwave Anisotropy Probe (WMAP) Observations: Final Maps and Results"}