Globus IMP instruments were spacecraft navigation instruments used in Soviet and Russian manned spacecraft. The IMP acronym stems from the Russian expression Indicator of position in flight, but the instrument is informally referred to as the Globus. It displays the nadir of the spacecraft on a rotating terrestrial globe. It functions as an onboard, autonomous indicator of the spacecraft's location relative to Earth coordinates. An electro-mechanical device in the tradition of complex post-World War II clocks such as master clocks, the Globus IMP instrument incorporates hundreds of mechanical components common to horology. This instrument is a mechanical computer for navigation akin to the Norden bombsight. It mechanically computes complex functions and displays its output through mechanical displacements of the globe and other indicator components. It also modulates electric signals from other instruments.
The IMP, in successively developing versions, has been used in Soviet and Russian manned space missions ever since the world's first manned spaceflight (Yuri Gagarin, 12 April 1961) through every manned Vostok, Voskhod and Soyuz mission until 2002.
The Voskhod spacecraft was the second generation of spacecraft designed in the manned Soviet space program, essentially an adaptation of the earlier Vostok spacecraft. It flew two manned missions, Voskhod 1 (world's first multi-crewed mission, launched on 12 October 1964) and Voskhod 2 (featuring the world's first Extra-vehicular activity, or EVA, commonly called a spacewalk, launched on March 18, 1965). The Voskhod spacecraft—and its Globus IMP instruments—is a close derivative of Vostok, which flew six Soviet individuals to low Earth orbit, including the world's first human in space, Yuri Gagarin, and the world's first woman in space, Valentina Tereshkova. The main difference between IMP versions 1 and 2 (Vostok spacecraft) and later versions (Voskhod and Soyuz) is the addition of the disc-shaped longitude and latitude indicators.