Indeed, I did a calculation that indicated that in order for it to accelerate in the way that it did recently, it must have, if it's a natural comet, it must have lost a substantial fraction of its mass of all the 20% or so. And we should see a very massive cloud of gas around it as soon as it comes out of the being hidden behind the sun. That should weigh of all the 5 billion tons of gas around it. If we don't see that, there must have been some other means of propulsion that gave it that acceleration. So that's very exciting.