I read a report recently on the extrasolar planet HD 209458b, which orbits very close to its star. It seems that the planet's atmosphere is being 'blown off' by the star's solar wind and is streaming away from it like a big comet. I thought it would be fun to try to simulate this, but I hit a snag.
I thought the simplest thing to do would be to change the planet's class to a comet, so that it would then have a 'tail'. So I simply added the words Class "comet" to its details. However, this doesn't seem to work. There's no tail.
I wondered if perhaps tails don't appear when the body is too big, so I tried making Halley's comet as big as Jupiter. This worked fine - it looked ridiculous, but it successfully gave Halley a vast tail.
So why doesn't it work for HD209458b? Any theories? There may be more important things in life, but it would look very groovy...
