0
If dark matter exists (the jury's still out on that, but it's looking pretty likely), then ... actually, you know what? We still don't really know, because we don't know exactly what dark matter IS. It may have been around since the beginning of the universe, or it may have formed slightly later. Either way, "around 13 billion years" is a good estimate.
What else can I help you with?
How long has justin bieber been afraid of the dark?
He's not afraid of the dark.
How long has deforestaion been around?
how long has deforestation been around
How long has guns been around?
As long as guns have been around.
How long has Mackenzie Falls been around?
As long as So Random has been around.
How long has the London eye been around for?
how long has the london eye been around for
How long has drama been around?
234 years fool
How long has boxing been around for?
how long have boxing been around?
How long has the Air Force been around?
boner
How long have numbers been around for?
They have always been around
How long was football been around?
The time football has been around for is a long timeFootball has been around for a long time but we do not know how long it has been around
How long has literacy been around?
For as long as there has been written language.
How long has you me at six been together?
it has been around for a long time.
