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Okay, ground rules: Space Shuttle has not been developed ITTL; instead, NASA has access to medium-lift vehicles (20-30 mT to LEO) and "light" heavy-lift variants of those vehicles (50-70 mT to LEO), ala Phase I/II Delta IV/Atlas V Heavy. For crew transport, they use a variant of the Apollo.

Using this equipment, NASA was able to build their space station, "Freedom," much, much more quickly than IOTL, so it's finished by late 1990 (last component launch in August). Politics is assumed to be unchanged by these different NASA activities, so Bush I is still in office. He wants to announce a new space initative in mid-1989, as per the OTL speech. Assume that people at NASA don't behave like idiots and are aware of political constraints, so nothing like the utter failure of the 90-day report will happen. The amount of planetary exploration done by NASA during the 1970s and '80s is comparable to OTL (that is, not much), except that the outer planets have been more throughly explored (in particular, there was a Pluto flyby a few years earlier).

Under those conditions, what types of missions are likely to be proposed, and what will NASA probably see as the broad outline of what it ought to be doing in the future? I mean, in the sense that IOTL during the late '80s NASA thought that it should build the station, go to the Moon, build a base on the Moon, and go back to Mars, in that order. So it proposed missions that would tie into that, like sending robotic explorers to the Moon and Mars, developing rockets that could transport the payloads needed for lunar and Martian missions, and so on.
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