Jupiter is coming into the evening hours.
On July 1 Jupiter rises a few minutes after midnight. On July 31
Jupiter rises a few minutes after 10 P.M. It will be known at once by
its brilliancy.
Besides the ordinary belts of Jupiter the planet still shows at this
time (June 10) the large ruddy spot spoken of by many persons some
weeks since. This spot is elliptical in shape; its longest diameter is
about one-fifth that of Jupiter. A small glass will show it, and the
ordinary observer can, by watching its appearance and disappearance
and reappearance, determine the time of rotation of Jupiter on its
axis, or the length of the planet's day.
The best evenings for looking at Jupiter are those of July 23, when
the satellite nearest to Jupiter goes across its face, preceded by
its shadow; July 28, when the first and second satellites will make
similar transits; and July 29, when Jupiter will rise without the
presence of its third satellite, which will be in eclipse, and will
come out of the shadow after midnight.