ROUGH ASTRONOMICAL NOTES

Evening Star, Issue 3750, 1 March 1875, Page 3

ROUGH ASTRONOMICAL NOTES

Mabch, 1875. |fl. The Sun enters the sign Aries on the 21st, just before noon; at this time autumn is technically supposed to commence. As our readers are aware, we are now not far from the period when the average number of spots is at its ' minimum. At such times it is not usually the case that large or interesting spots are to be seen, but on rare occasions they < do break out on the Sun even at the period of minimum solar disturbance. It is, therefore, never perfectly safe to say that the Sun’s disc is nearly free from spots, except after actual observation. The weather was very unfavorable on Saturday, but the Sun now and then shone out brightly for a minute or so at a time, but not long enough to allow the large reflector to bo brought to bear on it; but several satisfactory glimpses of it were obtained with a binocular field glass, which magnifies four diameters; and gives admirable definition. A very large spot was at once seen on the Sun’s disc. It appeared nearly or quite as large as Venus when it was in transit, and nearly as well defined; its diameter must, therefore.be at the very least 20,000 or 25,000 miles. We next tried to see it without any magnifying power at all. On our looking at the sun through a piece of colored glass, the spot became at once not merely visible, but perfectly obvious ; no one with ordinary eyesight could have failed to see it. Its position at 12 o’clock was about one-fifth or one-sixth of the i-un’s diameter from the W. limb (left side), of the Sun, and a few degrees below it, 2. The Moon will be at its least distance from the Earth on the 10th, at about 5 p.m. in the afternoon, and at its greatest at about 6 P-“- on the 26th; the phases will take place as follows New moon on the Bth, at about 7.45 a.m. First quarter on the loth, at about 12!28 a.m. Full moon on the 22nd, at about 11,14 a.m. Last quarter on the 30th, at about 8.47 p.m. High tides may be expected to occur soon after the period of new Moon, as at that time the Moon will be near its perigiec, and not very far, only some seven or eight degrees, from the Equator. 3. Mercury will be in inferior conjunction on the 2nd, but will be very favorably situated for some days before and after the 29th when he will be at his greatest elongation W,, 27' i degrees nearly. At that time he may be seen about half-way between Alpha Pegasi and Fomalhaut. He should be looked for about three-quarters of an hour before sunrise, when he will have reached a very considerable elevation (for him) in the eastern sky. 4. Venus is now waning very sensibly as she moves towards her superior conjunction with the Sun. She may be looked for in the mornmg on the borders of Sagittarius; on the 27th ehe will be m conjunction with Saturn. 5. Mars. The brilliancy of this planet is cow fast increasing. He may be well seen in the eastern sky at about midnight during the greater part of the month. He is now in the Scorpion, not very far from Antares, which he clearly excels in brightness: the colors of the two bodies are very similar 6. Jupiter will be in opposition next month, when we shall take the opportunity of givin" some account' of his present appearance. He also may be well seen at midnight, at which rime be now obtains a considerable altitude. Me is. situated ne o r the borders of the constellation Virgo not very far from Spica, which he follows (40. mm.) a little south. 7. Saturn now rises about- an hour and a quarter before the Sun, but he cannot be well observed till towards the encl of the month. *l6 is still in the constellation Capricorn. 8. Uranus is nearly where he was last month. He passes the, meridian at about a quarter past ten. 9. Neptune cannot now be seen. Note on the Solar Spot,—Towards evening on Saturday it was found possible to obtain a view of the spot through the BAi n . Browning reflector, with a power of 150. The air was not so unsteady as might have been expected; with this instrument the spot appeared very large pear shaped, and well defined at the edge. In the umbra, or black part, which appeared verv considerably larger than the planet Jupiter does with the same power, intensely black patches were to be clearly made out. The umbra was surrounded by a light buff-colored penumbra of about half the breadth of the umbra. Dark rifts were visible here and there in the penumbra, these being extensions of the umbra, fhe diameter of the entire spot must be at least 40,000 miles In the neighborhood of the great spot are other much smaller ones. A group of three moderate sized spots Were to be seen some distance below the great sno', with umbra, end penumbra complete ; while more towards the centre of the disc there was a fine spot which would be well worth examin ing, if it were not for the presence of its more interesting companion near the Sun’s limb Unless its size should diminish' very greatly in the interval, it should be well seen a»ain with the naked eye in about three weeks’ time.