Uranus and Neptune are so distant that telescopes of considerable
size and high magnifying power are necessary to show their disks.
In small telescopes they have the appearance of stars, and the
observer has no way of distinguishing them from the surrounding
stars unless he can command the best astronomical appliances, such
as star maps, circles on his instrument, etc. It is, however, to
be remarked, as a fact not generally known, that Uranus can be
well seen with the naked eye if one knows where to look for it. To
recognize it, it is necessary to have an astronomical ephemeris
showing its right ascension and declination, and star maps showing
where the parallels of right ascension and declination lie among
the stars. When once found by the naked eye, there will, of
course, be no difficulty in pointing the telescope upon it.
Of celestial objects which it is well to keep a watch upon, and
which can be seen to good advantage with inexpensive instruments,
the sun may be considered as holding the first place. Astronomers
who make a specialty of solar physics have, especially in this
country, so many other duties, and their view is so often
interrupted by clouds, that a continuous record of the spots on
the sun and the changes they undergo is hardly possible.
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