Heliometer observations of distance in their most refined sense cannot be considered absolute measures of angles.
To remedy drawback (2) Repsolds provided for the Yale heliometer an additional handle for motion in position angle, intermediate in velocity between the original quick and slow motions.
When the scales and position-circle of the heliometer have been set to these readings, the comet and the selected comparison-star appear together in the field of view.
There are three methods in which thisheliometer can be used.
His heliometer (described in a paper communicated to the Royal Society in 1743, and printed, along with a letter from James Short, in Phil.
A series of observations can be easily and more accurately accomplished with the Cape heliometer in half an hour; with the Oxford heliometer it would occupy 2 hours, and with the 4 in.
This lens is divided and mounted like a heliometer object-glass; the separation of the lenses produces the required double image, and is measured by a screw.
Gill introduced a powerful auxiliary to the accuracy of heliometer measures in the shape of a reversing prism placed in front of the eye-piece, between the latter and the observer's eye.
This particular instrument has historical interest, having led Struve to some of those criticisms of the Pulkowa heliometer which ultimately bore such valuable fruit (see ante).
Thus, for refined purposes, it cannot be assumed with any certainty that the instantaneous scale-value of the heliometer is known, or that it is a function of the temperature.
When the heliometer-part of Lord Lindsay's heliometerwas acquired by Gill in 1879, he changed the manner of imparting the motion in question.
Bessel's application of the heliometer to measurements of stellar parallax.
Thus, from 606 measures of Venus on the sun, taken with a new kind of heliometerat Santiago in Chili, M.
They frequently recur; they need no elaborate preparation; a single astronomer armed with a heliometer can do all the requisite work.
The most noteworthy forward steps in improving the heliometer are due to the celebrated instrument-makers of Hamburg, the Messrs.
A rival method to that of the heliometer has been discovered in the photographic telescope.
He considered that, while the superiority of the heliometer had been proved, the results would be still better with the points of light shown by minor planets rather than with the disc of Mars.
The superiority of the heliometer over all other devices (except photography) for measuring small angles has been specially brought into prominence by Sir David Gill's researches on the distance of the sun--i.
These require extension, because the differential methods of the heliometer and the camera cannot otherwise be made absolute.
The measures on a single night with the heliometer should not have a mean error greater than one-fifth of a second, and we might reasonably expect that observations could be secured on about twenty-five nights during the opposition.
The heliometer is a telescope with its object-glass cut in half along a diameter.
The above list will hopefully give you a few useful examples demonstrating the appropriate usage of "heliometer" in a variety of sentences. We hope that you will now be able to make sentences using this word.
