226 



KNOWLEDGE & SCIENTIFIC NEWS. 



[Sept., 1904. 



TKe Face of tKe Sky for 

 September. 



By W. Shackleton, F.R.A.S. 



The Sun. — On the ist the Sun rises at 5.14, and sets 

 at 6.46 ; on the 30th he rises at 6.0, and sets at 5.39. 

 The equation of time is zero on the ist. 



Autumn commences at noon on the 23rd, when the 

 Sun enters the sign of Libra. 



There is a total ecHpse of the Sun on the 9th, invisible 

 in Europe, the shadow path lying entirely over the 

 Pacific Ocean. 



Sunspots, facuLT, and prominences are fairly numerous; 

 at the time of writing, three groups of spots, as well as 

 a considerable amount of faculae, are visible. 



The positions of the spots, &c., with respect to the 

 equator and poles may be derived by employing the 

 following table : — 



The Moon :- 



Sept. 9 

 .. 23 



Perigee 

 Apogee 



7 12 p.m. 

 6 o a.m. 



OccuLTATioNS. — The Moon passes through the 

 Hyades about midnight of the 29th, when many of the 

 stars are occulted ; Aldebaran suffers occultation soon 

 after sunrise on the morning of the 30th. 



The Planets. — Mercury is in inferior conjunction 

 with the Sun on the i6th, after which date he is a morn- 

 ing star in Leo. 



Venus sets too soon after the Sun to be suitable for 

 observation. 



Mars is a morning star on the confines of Cancer and 

 Leo, rising about 2.25 a.m. on the 15th. 



Jupiter is the most conspicuous object in the sky, look- 

 ing nearly due E. about g p.m. On the 15th he rises at 

 7.15 p.m., and is on the meridian at 2.16 a.m. The 

 equatorial diameter of the planet on the 14th is 48"-4, 

 whilst the polar diameter is 3"-i smaller. 



The planet is near the Moon on the e\-ening of the 

 26th. 



The configurations of the satellites, as seen in an in- 

 verting telescope at 12.30 a.m., are as follows: — 



The circle (O) represents Jupiter ; signifies that the satellite is 

 on the disc ; 9 signifies that the satellite is behind the disc, or in 

 the shadow. The numbers are the numbers of the satellites. 



Saturn is a very conspicuous object in the sky looking 

 S. about 10 p.m. ; he is on the meridian at 0.30 p.m. near 

 the middle of the month, and although rather low down 

 in the sky he well repays observation, for even with sinall 

 instruments the planet is a beautiful object. The polar 

 diameter of the ball is iy"-o, whilst the major and minor 

 axes of the outer ring are 42"'5 and ii"-/ respectively; 

 thus the ring plane is inclined to our line of vision at an 

 angle of 16", the northern surface being visible. 



Uranus is on the meridian about 6 p.m. near the 

 middle of the month, hence the best time for observation 

 is immediately after sunset. He is practically stationary 

 throughout the month, and is situated about 12 minutes 

 W. of the star 4 S.Tgittarii. 



Neptune does not rise until after midnight. 



The Stars : — 



At the beginning of the month, at 9 p.m., the following 

 constellations are to be observed: — 



Zenith . Lyra, Cygnus. 



South . Aquila, Delphinus, Aquarius, Capri- 

 cornus, Sagittarius; Serpens, Ophiuchus, and 

 Scorpio to the S.W. 



East . Andromeda, Pegasus, Pisces, and Aries ; 



Pleiades on horizon. 



West . Hercules, Corona, Bootes. 



North . Ursa Major, Ursa Minor ; N.E., Cassio- 

 peia and Perseus; .Auriga (CapcUa) low down. 



Minima of Algol occur on the 6th at 9.53 p.m., 9th at 

 6.42 p.m., 26th at 11.36 p.m., and 2gth at 8.25 p.m. 



Telescopic Objects: — 



Double Stars :-— r Ursa- Majoris XHI.h 20'", N. 55° 26', 

 mags. 2, 4; separation I4"'4. 



j- Aquarii XXII.'' 23™, S. o"-35', mags. 4, 4, separation 

 3"-2. Both components are yellowish. 



fl Cygni XlX.h 27"^, N. 27° 45', mags. 3, 5 ; separation 

 34". The brighter component is yellow, the other blue; 

 very easy double in small telescopes with a power of 20. 



Cluster (M 11) in Aquila or Antinous. K.A. iS" 46" 

 Dec. S. 6 23'. Very pretty object for 3 or 4 inch tele- 

 scope ; it is an easily resolvable fan-shaped cluster, with 

 an Sth magnitude star in apex and an open pair of the 

 same magnitude just outside it. 



