Double-star Sentence Examples
For the measurement of wider stars he invented his lamp-micrometer, in which the components of a double star observed with the right eye were made to coincide with two lucid points placed io ft.
This angle, therefore, divided by the magnifying power of the telescope gives the real angular distance of the centres of a double star.
I, 2 and 3), used to bolt the head of one of the screws, and the instrument was provided with a slipping piece, giving motion to the micrometer by screws acting on two slides, one in right ascension, the other in declination, so that " either of the, webs can be placed upon either component of a double star with ease and certainty (Mem.
In estimating theoretically the resolving power on a double star we have to consider the illumination of the field due to the superposition of the two independent images.
If the angular interval between the components of a double star were equal to twice that expressed in equation (15) above, the central disks of the diffraction patterns would be just in contact.Advertisement
In 1812 Bessel measured with it the angle between the components of the double star 61 Cygni and observed the great comet of 1811.
Struve also points out that by attaching a fine scale to the focusing slide of the eye-piece, and knowing the coefficient of expansion of the metal tube, the means would be provided for determining the absolute change of the focal length of the object-glass at any time by the simple process of focusing on a double star.
Simi larly the prism may be used for the study and elim- " ination of personal errors depending on the angle made s by a double star with the vertical.
Ursae majoris is perhaps the best known double star in the northern hemisphere, the larger component is itself a spectroscopic double.
It is a legitimate speculation to suppose that these in the reverse order are the stages in the evolution of a double star.Advertisement
There is a lovely double star called Epsilon Lyrae up and to the left of Vega.
With magnitudes 3.1 and 5.1 they are regarded as the most beautiful double star that can be seen in the sky.
To observe the position-angle of a double star it is only necessary to turn the position-web so that it shall be parallel to the line joining the centres of the components of the double star.