The "comet" is close enough for Titan missiles to reach it in a couple of minutes, and then is shown to be passing the moon on its way to Earth.
Errors in geography
In the pilot episode, Lily and Richard talk in a coffee shop. At one point, a TransLink trolley bus passes by the window. TransLink is the public transit authority of Vancouver, where this was filmed.
In the street scenes of Episode 1.2, street lamp banners show that the location is the Commercial Drive neighbourhood of Vancouver.
The Titan missiles continue to show contrails as they approach the "comet" even though the comet is in space. Rocket contrail would require atmosphere to form.
The US launched 24 Titan II missiles at the "comet". The last Titan II missile was decommissioned in 1987.
The object heading toward Earth is projected to land at a location described in degrees "north longitude" and "west latitude".
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