[Scully]

This is because no past observations - that could be used to pinpoint its trajectory - have been found in astronomical archives. This is because the asteroid's unusual orbit takes it into regions of space that are seldom surveyed,/p>

Wait a tick...they have only ONE data point and they have already decided we're in the clear???

[Scully]

Since then astronomers worldwide have been paying close attention to it, amassing almost 200 observations in a few weeks.

I stand corrected...pardon.

[RightWhale]

True the need three observations to get a solution. However, if the three points are close together the orbit will be known less well than if the three points are spread out more. The other thing is that the orbit will change when the body is deflected by passing through a gravity well or if it collides with something. So they will need to track this one and all the others from here on, plus they will need to keep tracking it even if they deliberately deflect the orbit becuse it will come around again.