Rufus T. Firefly wrote:webenda wrote: Twenty four elements on the Periodic Table were created by man.
I must be out of date - I'm not getting quite that high a number.
- Count, Element name, Symbol, Atomic number, First definite synthesis date
1 Americium Am 95 1944
2 Curium Cm 96 1944
3 Berkelium Bk 97 1949
4 Californium Cf 98 1950
5 Einsteinium Es 99 1952
6 Fermium Fm 100 1952
7 Mendelevium Md 101 1955
8 Nobelium No 102 1966
9 Lawrencium Lr 103 1971
10 Rutherfordium Rf 104 1966 (USSR), 1969 (US) *
11 Dubnium Db 105 1968 (USSR), 1970 (US) *
12 Seaborgium Sg 106 1974
13 Bohrium Bh 107 1981
14 Hassium Hs 108 1984
15 Meitnerium Mt 109 1982
16 Darmstadtium Ds 110 1994
17 Roentgenium Rg 111 1994
18 Copernicium Cn 112 1996
19 Nihonium Nh 113 2003–4
20 Flerovium Fl 114 1999
21 Moscovium Mc 115 2003
22 Livermorium Lv 116 2000
23 Tennessine Ts 117 2010
24 Oganesson Og 118 2002
* Shared credit for discovery.
Rufus T. Firefly wrote:And, while they were created here by man, I'm not sure that that some might exist transiently in very old stars.
I agree but not relevant to the claim that these elements were brought to Earth by comets.