"The offing" is either the deep part of the sea as visible from the shore, or something likely to happen or manifest itself soon... (ie, metaphorically on the horizon).

I'd like to share a few links to DiscoverMagazine.com/Aliens  It's the sort of blog I ought to have found years ago!  This article, about Tabby's Star is great inspiration, and is also fascinating for the comments. KIC 8462852 might be too far off to be "in the offing"! It has a mysterious flicker.
http://blogs.discovermagazine.com/outthere/2016/07/31/alien-megastructure-star/

This article is about how to dupe aliens into thinking that Earth has no oxygen, and other ways to not attract undesirable alien attention, 
http://blogs.discovermagazine.com/d-brief/2016/03/31/hostile-alien-protection-plan/

Please scroll down to enjoy the guest blog from Friday/Saturday.

All the best,
Rowena Cherry