ζ Mon - Optical double star. The primary component has a brightness of 5mag, its companion has a brightness of 8.5mag. It is located at a separation of 66.4". Another companion can be found at a distance of 32". We need a telescope with a 7cm diameter objective.

ε Mon - At the main star with a brightness of 4.5mag, there is a companion at a separation of 13.4" with a brightness of 6.5mag, which can be observed even with a smaller telescope. Both components have a yellow color. At a distance of 93.7" from them, a faint blue companion with a brightness of 12.7mag can be revealed with a larger telescope.

β Mon - The brightest star of the constellation has an apparent magnitude of 3.95. It belongs to a beautiful triple star system discovered by W. Herschel in 1781, whose all blue-white components can be resolved even with small telescopes as a small triangle. Two components with magnitudes of 4.7 and 5.2 are located at a separation of 7.3 arcseconds. A companion with a magnitude of 6.1 is situated at a distance of 2.8 arcseconds from the first component. The system is approximately 700 light-years away. With a larger telescope, we can also discover a star with a magnitude of 12 at a separation of 25.9 arcseconds. This entire system is designated as 11 Mon.

Plaskettova hviezda - Astronomický text:

A spectral binary star of sixth magnitude, discovered in 1922 by Canadian astronomer and director of the Victoria Observatory, John Stanley Plaskett. It is the most massive known binary star.

Překlad českých zkratek světových stran:

N - North W - West S - South E - East