It looked much closer than Johnston Island. The
elevation of the circle was perhaps 20° above the
horizon.
Operation HARDTACK I Nuclear Events, 1958
Event
Date
Type
Yield
YUCCA
28 April
High Altitude
(Balloon)
NA*
Surface
18 kilotons
CACTUS
6 May
FIR
12 May
Barge
NA
BUTTERNUT
12 May
Barge
NA
KOA
13 May
Surface
WAHOO
16 May
Underwater
NA
HOLLY
21 May
Barge
NA
NUTMEG
22 May
Barge
NA
YELLOWWOOD
26 May
Barge
NA
MAGNOLIA
27 May
Barge
NA
TOBACCO
30 May
Barge
NA
SYCAMORE
31 May
Barge
NA
1.37 megatons
ROSE
3 June
Barge
NA
UMBRELLA
9 June
Underwater
NA
MAPLE
11 June
Barge
NA
ASPEN
15 June
Barge
NA
WALNUT
15 June
Barge
NA
LINDEN
18 June
Barge
NA
REDWOOD
28 June
Barge
NA
ELDER
28 June
Barge
NA
OAK
29 June
Barge
HICKORY
29 June
Barge
NA
SEQUOIA
2 July
Barge
NA
CEDAR
3 July
Barge
NA
DOGWOOD
6 July
Barge
NA
*
Not announced
120
8.9 megatons