These small bodies have now become so numerous that it is a matter of much difficulty to follow them. At the meeting of the Royal Astronomical Society on January 8, 1909, Mr. G. F. Chambers made the following facetious remarks—
“I would like to make a suggestion that has been in my mind for several years past—that it should be made an offence punishable by fine or imprisonment to discover any more minor planets. They seem to be an intolerable nuisance, and are a great burden upon the literary gentlemen who have to keep pace with them and record them. I have never seen, during the last few years at any rate, any good come from them, or likely to come, and I should like to see the supply stopped, and the energies of the German gentlemen who find so many turned into more promising channels.”
Among the minor planets numbered 1 to 500, about 40 “have not been seen since the year of their discovery, and must be regarded as lost.”[129]
CHAPTER VIII
Jupiter
This brilliant planet—only inferior to Venus in brightness—was often seen by Bond (Jun.) with the naked eye in “high and clear sunshine”; also by Denning, who has very keen eyesight. Its brightness on such occasions is so great, that—like Venus—it casts a distinct shadow in a dark room.[130]
The great “red spot” on Jupiter seems to have been originally discovered by Robert Hooke on May 9, 1664, with a telescope of 2 inches aperture and 12 feet focus. It seems to have existed ever since; at least the evidence is, according to Denning, in favour of the identity of Hooke’s spot with the red spot visible in recent years. The spot was also observed by Cassini in the years 1665-72, and is sometimes called “Cassini’s spot.” But the real discoverer was Hooke.[131]
The orbit of Jupiter is so far outside the earth’s orbit that there can be little visible in the way of “phase”—as in the case of Mars, where the “gibbous” phase is sometimes very perceptible. Some books on astronomy state that Jupiter shows no phase. But this is incorrect. A distinct, although very slight, gibbous appearance is visible when the planet is near quadrature. Webb thought it more conspicuous in twilight than in a dark sky. With large telescopes, Jupiter’s satellites II. and III. have been seen—in consequence of Jupiter’s phase—to emerge from occultation “at a sensible distance from the limb.”[132]