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Can't find the tutorial that would be perfect for you, but basically wooden beads on a stick with hardend clump foliage stuck on explosion wise.The ball would be the expanding hot gas, so red/yellow/blue fire, the tufts mostly black and the very tips red/yellow/white bright burning bits of wreckage.
There are some nice images I've seen in the past.Check Google Images for ideas.Depends upon if you want to sacrifice minis, or not, to really sell the overall effect.If not, perhaps just some appropriately colored pieces of polyfill fiber, like they stuff pillows with, would work. Mount them on a flight stand, as desired.
Another idea might be to use some expanding foam.The trick is that you won't really have wispy or thick smoke in a space explosion. It's pure boom (and debris).
This is something along the line Gunbird mentioned. Using clump foliage. I had a link to another tutorial but it is dead now. Curse you internet http://mindfad.blogspot.com/2012/10/air-burst-round-3.html-A
Amazing how fast time flies while Googling......anyhoo:http://www.forum.specialist-arms.com/index.php?topic=8492.75....the puffy balls look more like what I mean, but then add clump foliage to that and more black. Really wishing I had saved that page the odd 10 years ago I actually saw it.....