It just missed the mark. It was shot Academy, shown 1.85-1 in theaters that had already remodeled their screens. Here is the chronology—

ICFOS shooting dates: February 10 to March 7, with one day of retakes on April 17.

March 13: Universal visits the Paramount lot to see their new 1.66-1 widescreen system.
March 17: Universal visits the Fox lot to see CinemaScope
March 26: Screening is held on Process state at Universal to demonstrate to Universal personnel widescreen/3-D/stereophonic sound. Scenes from WORLD IN HIS ARMS, THUNDER BAY and DESERT LEGION are shown at ratios of both 1.66-1 and 1.85-1 on a 50' x 25' screen. Scenes from IT CAME FROM OUTER SPACE were also probably shown.
March 27-April 6: General screenings for other studios, the press, and exhibitors.
April 7: THUNDER BAY is screened for Uni. Personnel at 1.85-1.
Week of April 13: THUNDER BAY is re-dubbed for stereo.
Late April: New screen is installed at the Loew's State in NY.
May 20: THUNDER BAY premieres at the Loew's State.
May 27: IT CAME FROM OUTER SPACE premieres at the RKO Hillstreet and Pantages.
July 30: All viewfinders on Universal cameras are retooled from 1.85-1 to 2-1.