Thursday, July 9, 2015
Let's hide the task force in a nebula!
But one episode made me smile. The Jedi ships came out of hyperspace on the edge of a nebula, the plan being to sneak up on Grievous's flagship (on the other side of the nebula) without being noticed. There are two things a little bit dodgy about that.
The images in the cartoon showed the ships moving through a thick mist that looked a bit like the colour-enhanced image of Orion above. The reality is a bit different. If you look at the Orion nebula through a telescope it looks like a white mist. But surely the nebula would look very different up closer? Er, no. The nebula will look larger, meaning the light is dispersed over a larger area. This explains it rather well. So rather than sneaking up through a pea soup fog, the ships wouldn't even be going through a thin mist. #Fail.
But that's not all. So we come out of light speed at the edge of the nebula, right? Planning to take a shortcut through the billowing clouds. Well... nebulae are not localised patches of mist. Or at least, they are, for a given meaning of localised. As a ferinstance, the Orion nebula is 24 light years across. And it isn't even a big one. Assuming Grievous's flagship is on one side of the nebula and the Jedi force is on the other, the "shortcut" is going to take an awfully long time in normal space.
Hey - it's fiction. We all know Star Wars ships behave in vacuum the same way they would in atmosphere, don't we? But the reason I smiled when I watched the episode is because I knew those facts, having researched nebulae for a book I was writing at the time.
Gosh. Is there an elephant in this room?
However... the Universe is a remarkable place. You have only to look at the mind-boggling diversity we have already found in exo-planets. So perhaps, somewhere out there, we'll find tiny, dense nebulae as thick as a London fog that will hide strike forces. Who knows?