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ON December 15 a photograph of the satellite 1957 Beta was taken at the Warner and Swasey Observatory of the Case Institute of Technology, Cleveland, Ohio, which shows the satellite coming out of the Earth's shadow (Fig. 1). This observation can be used for deriving the distance of the satellite from the Earth's surface. It was concluded from visual observations made the previous morning that the satellite should leave the Earth's shadow in the constellation Ursa Major. An exposure, therefore, was started at 5h. 10m. OOs. E.S.T. with Ursa Major in the centre of the field, although the satellite was not yet visible. The satellite was first observed visually between 5h. 10m. 20s. and 5h. 10m. 30s. It is estimated that it came out of the shadow not earlier than 5h. 10m. 10s. The position where the track is first recorded on the photograph is α = 11h. 53m., δ = + 54.8°. It is possible that the satellite at this position had already left the shadow, but was not recorded earlier because it was at minimum brightness. Nevertheless, since the period of light variation was about 40 sec., the real position should be between the value already given and α = 11h. 37m., δ = + 61°. From these two positions, heights above the surface of 770 and 800 km. respectively were derived, assuming a spherical Earth and a cylindrical shadow with a radius equal to that of the Earth. If refraction isrtaken into account, smaller values of the height result. Assuming a deflexion of the light rays from the Sun of 1°, the corresponding heights are 713 and 739 km. It would appear then that the derived value of 785 ± 15 km. is a maximum one. From predictions of the Smithsonian Institution a height of about 1,000 km. was expected. According to our observations this is too large by at least 200 km.

LAST night, between 8 and 9 p.m., there was visible here a very fine display of Northern lights, the finest indeed that I have yet witnessed. The sky was nearly unclouded, and the moon had not yet risen; a band of light forming an arc extended from west to east, under the Polar Star. It just touched, by its upper boundary, the stars γ and β of the Great Bear, and nearly touched by its lower fringe the star Cor Caroli; this gives some idea of its breadth. Beams of light extended from the upper fringe towards the North Star, with greater or less intensity, fading away, however, very rapidly. Towards 9.30 p.m. the eastern end of the arc became very luminous; immense beams spread up into the heavens, mostly parallel to the direction of the pointers. On the extreme east, a portion of the aurora presented that beautiful violet tint which is so relatively rare in these latitudes. Some of the beams towards the centre of the arc also presented this colour, but only momentarily.

AN exceedingly beautiful meteor, one of the finest I have seen, was observed from this vessel, while at sea, on the night of July 31. The time of observation was 10h. om. ship's apparent time, or 13h. om. G.M.T., the position of the ship at the time of observation being latitude 43.34° N., longitude 43.37 W. The duration of the flight was between fifteen and twenty seconds, and the meteor was much more brilliant than Venus. It pursued an almost horizontal course, about 8° above the horizon, passing below the constellations Ursa Major, Perseus, and Aries, in all traversing an arc of about 135°.

A VERY fine shower of shooting stars was observable at Boltsburn, Rookhope, in Durham, on Wednesday night (27th inst.). I first noticed them about half-past seven, when they were very numerous; their directions were chiefly downward, towards nearly all points of the horizon. The radiant point seemed to be situated near the Great Bear, but of this I could not make myself perfectly satisfied. They varied much in magnitude and length of track. Some of the larger ones left a streak of reddish light on their track, which lasted a second or two. About eight o'clock I counted, in fifteen minutes, 600, which came within my field of vision from a doorway having a southerly exposure. The regularity of occurrence was such as to approximate closely to 200 during each five minutes. How long the phenomenon continued in the latter part of the night I had not the opportunity of ascertaining.

WITH reference to your note in NATURE of August 16 referring to a magnetic storm on the night of August 9–10, it may be of interest to learn that an aurora was seen here that night. It was first seen a few minutes before 10 p.m. (G.M.T.), when it appeared as a glow in the northern sky. Two streamers were lust discernible at first, but they gradually increased in numbers and became clearer, at the same time growing longer and brighter and moving towards the west. The longest reached to the centre of the Great Bear. Small, sharp, and delicate streamers, although not prominent, were distinctly seen in the larger streamers. There was no colouring seen at all, but merely a white glow. By 11.15 all traces of it had vanished.

SINCE my last remarks I have had an opportunity to examine this fine object with the 6″ Cooke equatorial. On Wednesday evening, the 24th, simultaneously with the Great Bear stars, it was easily seen as soon as twilight set in, near the horizon and considerably more to the west than on the 21st. With a comet eyepiece it presented, in spite of its low altitude, a sharp and well defined figure. The nucleus was stellar-like, with, I thought, a still brighter minute central point. No jets of light proceeded directly from it, but it appeared surrounded by a circular nebulosity of greater extent than the base of the tail, and giving the headed form to the comet frequently seen in old drawings of these objects. The tail was straight, long, and luminous, with a central ray of condensed light which gave it a cylindrical look. When first examined three small stars were involved in the tail without any apparent diminishing of their brightness; while two others below served to define the limit of the tail's visibility in the comet eyepiece. This measured two degrees only, but both it and the nucleus were of a peculiarly fine pale blue tint. I send a drawing of the telescopic appearance of the comet at 8h. 40m. On the nights of the 27th and 28th the comet was again examined at about 8h. 30m. Under a lower power Kellner the appearance was that of a round comet with a central nuoleus and circular coma. The tail was to be seen, bait was quite faint, and as before was less at the base than the width of the coma. Dr. ?de Konboly I are has examined the specturm of this comet, and found it a faint continuous one, with three telrably bright lines, at following positions:—

ON the night of January 3 some fine meteors were observed here. It is doubtful, however, if any of them were directly connected with the radiant that has given this early January shower its name. Possibly the first meteors observed shortly before ten o'clock may have issued from the neighbourhood of Bootes, as it shot upwards from the direction of the Great Bear with a brilliancy sufficient to attract attention in a lighted thoroughfare, from where, however, its starting point could not be clearly ascertained. During a watch kept under more favourable conditions for observation, between 10.30 and 11.30 G.M.T., four or five shooting stars were observed, the brightest of which scarcely equalled a second magnitude star, its path extending from Gemini to the east of Ursas Major. The others were seen flashing to the east of the latter constellation with no well-defined centre of radiation. It should have been stated that in a ten minuites' watch between 10 and 10.30 a stationary meteor more brilliant than a first magnitude star appeared for about half a second midway between the Quardrantid radiant and Ursa Major. This was the only meteor seen that may perhaps be regarded as comformable to the radiant proper, though almost exclusive attention was given to that part of the sky. Though occasionally a look out was kept from 12 to 1 a.m., no shooting stars were seen, but in an unbroken watch from 1.15 to 1.45 a.m. a brilliant bolide was observed at 1.40 gliding down evidently from the neighbourhood of Gemini towards the Great Bear, and throwing off several fragments near the end of its path. It was the brightest meteor seen during the night. The night of the 3rd was very fine here, though a few clouds interfered somewhat with observation between 10 and 10.30.