The initial plan is to delve deeply beneath the island of Manhattan in order to re-start the great pillar that keeps Manhattan afloat (right now, the only thing keeping the island above water is a compressed layer of dead rats). This will require the refined oil drawn from the wells beneath, but the inlet doors are stoppered up by silt, muck, and petrified twinkies.
Once the pillar returns to its rightful rotation, the island will rise revealing why Central Park was really a bunch of landlocked floating islands. It will also reveal which of these floating islands contains the Spectral Cache (alien technology that exists simultaneously across Planes of Existence 1, and 4 through 6) holding the New Mayan Calendar.
This will then be jettisoned using the alien ship escape pod trapped in amber and ratshit beneath the Museum of Natural History. The Museum will be severely damaged in the process, but I feel it's a price worth paying. The escape pod with exit Earth's atmosphere and slingshot around the moon for extra speed. Planetary placement will exponentially increase the inertia already in place at takeoff via a column of lessened gravity created by a northern front, force radiance from the moon, and a Monarch butterfly fart. This would also reset the moon's orbit to a respectable distance reducing the frequency of weather-derived disasters.
At optimum inertia, the alien escape pod will make contact with the asteroid threatening Earth destroying both the alien fuel source that would allow humans to destroy their race 10 years sooner than predicted by the New Mayan Calendar and the Calendar itself. There are other secrets it would reveal, but seeing as how humans exist longer when on a Mushroom Diet (kept in the dark and fed bullshit), this is another cost well worth paying.
With the asteroid destroyed (sadly not taking Bruce Willis with it), Manhattan re-aligned for another century, and the moon keeping Earth's gravity stabilized with the aid of the pyramids and resonance of amethyst geodes stored in the head of the Sphinx, the human race will persevere. At least...for 3/4 of another century.
I will, of course, remember to take a photo with the New Mayan Calendar for posterity sake. It will be framed and placed on my mantle, unknown to those that see it that it is NOT actually a novelty picture I had made for a laugh, but a prediction I can exploit before anyone else.
Bein' my usual goofy self. ;3