when did the crab nebula explode

Keyword Analysis

Keyword	CPC	PCC	Volume	Score	Length of keyword
when did the crab nebula explode	1.56	0.9	4140	71	32
when	1.54	0.4	3255	54	4
did	1.45	0.3	2432	48	3
the	0.09	0.9	536	21	3
crab	0.64	0.1	8867	73	4
nebula	1.85	0.5	7231	60	6
explode	1.1	0.3	9993	44	7

Keyword	CPC	PCC	Volume	Score
when did the crab nebula explode	0.14	0.5	6681	95
what did the crab nebula explode into	1.94	0.5	5308	57
when was the crab nebula discovered	0.89	0.9	9950	58
when was the crab nebula first seen	1.05	0.1	6151	23
when did the crab nebula supernova occur	1.34	0.3	3715	17
when was the crab nebula formed	0.05	0.3	7443	43
history of crab nebula	0.59	0.5	3728	65
who discovered the crab nebula	0.71	0.6	2425	95
what caused the crab nebula	0.49	1	5391	95
how was the crab nebula created	0.58	0.4	7793	34
how did the crab nebula form	1.19	0.9	802	70
the crab nebula facts	1.39	0.9	5487	73
pictures of the crab nebula	1.96	1	3540	26
images of the crab nebula	1.76	0.2	9040	83
nasa crab nebula image	1.79	0.7	2557	30
crab nebula nasa photos	0.09	0.9	3765	88
astronomy crab nebula news	0.3	0.4	3547	20
age of crab nebula	1.66	0.8	1309	11
fun facts about crab nebula	1.83	0.3	1033	63