| 摘要 |
An apparatus for use in demonstrating astronomical phenomena comprises a frame structure (12) and a pair of mutually spaced star bodies (13 and 14) mounted thereon. Each star body includes a representation of fixed stars defining a spherical surface part and is rotatable in relation to the frame structure about a point substantially coinciding with the centre of the respective spherical surface part. A light source is arranged at the concave side of the spherical surface part of each star body so as to project light through at least part of said representation onto a screen (11) by means of a lense system (35). The representations of fixed stars on the star bodies (13 and 14) preferably define in combination a representation of substantially the total celestial sphere, and means are provided for rotatively moving the star bodies simultaneously and synchronously, whereby a desired picture of fixed stars may be projected onto the screen (10). A plurality of representations of celestial bodies, including planets, the sun and/or the moon, may be projected onto the screen (10) by means of separate projectors (41-43) and moved along apparent orbits in relation to the projected fixed stars. |
