ASTKo\"MK AL PROGRESS fN 1897. 



The number thu< far dtscorertd average* 89 to * 



r nf variable* scattered o\ 



.or the l-st rr|N>rt 

 fl dfarowrvd nnd nblMMQ the 



... . . ; : s . < ; .. . A luilfl I v 



ar* nuvlljr mu them, bayoad the rwirh of Mr William 

 he) and of all northern observatories. Isaac 

 Robert* in photographing rlu.ion. nnd nebub 

 found on life ncgalivc plaUw I? now nebula* . 



aUloglM. On. in riffht MCen-i-.n 



1*^ !*>; drdinaiion north 96* 87 &'. is remark 

 , N f . , , li-noii* 



.... -, ,, . , , ., .,; li, 



nrarlv as largr and 

 . nebula. 



. forming <t Mraight 

 jular.as he says, that this 

 so Ion* mi* " ni,-r. 



r. can not wilwcribe to his opinion, that it 



v .. || ;:,_- t ||C DOSl 



half century. If h.- t- right in his bold eondu-ion. 

 it raises a new and curious question of mighty im- 

 port. Astronomer* are familiar with n.-.\ rtan, but 

 the advent of new nebula* is a novelty needing in- 



' 



latlonnof Men-no. Ncniis. and 1 ran us. 

 Herr Leo Brenner, of the Hanoni Observatory, 

 claims that he has determined the rotati n periods 

 of all the* planets. He has forwarded JO drawings 

 of Mercury, which show not onlv evidence of change 

 in the planet's markings, but also polar M,,,U 

 which on one occasion were as bright as th 

 the poles of Mars, from which he argues that the 

 observed markings prove that the slow rotation of 

 the planet in eighty-eight days is an impossibility. 

 The discussion of the rotation periodsof Mercury and 

 Vena* has assumed vast proportions, with exhibi- 

 tion of some as|*nty. In Monthly Notices" for 

 January, 1897, Percira) Ixwcll. from his private 

 observatory at Flagstaff, Ari/ona, publishes some 

 interesting observations made by him on Mercury 

 and Venus. He finds the markings on Mercury to 

 be conspicuous, and easier, in comparison, to see 

 than any of the markings on Mars except the seas. 

 Thrv were visible at all times when the seeing was 

 food. Those on Venus are long and narrow, and 

 perfectly distinct . The disk is quite dear ,,f clouds 

 and is brightened by a luminous atmosphere. There 

 it no evidence of the existence of polar ice caps. 

 Prom careful drawings, he concludes t hat t he jenod 

 of rotation is undoubtedly equal to her revolution 

 two hundred and twenty-live days. In a rcct-nt 

 number of the - Publications of the Astronomical 

 Society of the Pacific." IW. Holden says that he 

 has observed Venus from 1873 to 1880, with tele- 

 scopes of 6, 16. 26. and 36 inches apert un-. without 

 seeing mark ing* of the kind depicted bv Mr. Lowell. 

 and add* : - I have no hesitation in saying that such 

 marking* as he has shown did not exist on \ 

 before 18BO. nnd it is my opinion that they do not 

 now exist on the planet, but are illusions of 

 sort." Hrrr Brenner makes the rotation period of 

 theplanet Uranus about eight and a quarter hours. 

 rm. The long-disputed question of the value 

 e compression of Mars has at length l.n 

 settled beyond further controversy. The eye. i,, 

 Bewaring disks, is influenced by errors of estima- 

 tion in different directions with respect to th. 

 ticalline. Since the use of small r 

 on the eyepiece of the heliometer has bern a/1' 

 in which the diameter of a planetary di-k can be 

 made to appear in any direction with rasped to the 

 vertical, it is possible t< 



normal eye estimations. Prof. W. Schur. of the 

 Rand Om rratofjr, QOtttngi ;..-_. u. p* i 

 bcliometcr objective of 162 millimetres in diac 



armed with a power <-f 171. from tlio menu of Ber- 

 th* equatorial diameter 

 .ml the jM.lar Mpiv^ioii = ^ 



the ^..utli jiolar -|>ol on 

 for belief 



that ! -'liter \\:c* not \arie.l fo|- 



. Ired \ears. and that after entire 



.in form around 



HIM- jHiint. During the opposition <>f .Margin 

 1M96 111- i i lie polar cap was watched 



with great intercut after, its disappearance in i s '.'i. 



rulli was the lir-l to delect the newly formed 

 n .lime. l^!n. and from his microniel Heal 



measures the following oo-ordi tiedue.Mi: 



Areograpli : ,,lar li-iance. 

 .Martian of six Immlreil 

 which for the north- 

 ern hemi-pher. Imted as follow 

 one hundred and ninety-four: summer, one hun- 

 dred and seveiily--ix: autumn. hundred and 



; \vo ; and \\inter. one hundred and lift 

 < oiitirmalory of the existence - aid seas on 



m. -lit of < 'apt. I'. B. MolesWorth, of 



h a relli'cling b : '.'i in-h. - 



aperture, without any previoi^ knowledge of S-hia- 



pAralu's dnwingi. hM dnwn the canals and seas, 



which differ but little from tho-,- of Sehiajiarelli. 



hers. Other a-troiioim-rs be 

 mentioned above have filed claims to their 

 di-eo\-erie>.. notably Jb-rr I'.renner. who claim- to 

 -een as nmm a- :;i i-anaN not 1 ; -,led. 



During the last opposition the canals were seen 

 d'>ul' \n important point. 



if true, 'in connection with the doubling "f the 

 canals, is the liability of some of the .i 

 called lakes, to become double also, which rai-cs the 

 <|iie^tioti whether the duplicity of the 

 not after all an optical IllntiOQ OMind by SOUP 

 feet iii the eye or the telescope. 



Asteroids. The following iftt*roids,or planet- 

 oids, or minor planets, as they are variously called, 

 the last report : 



The following have received names: 



Jllpitor. The rapid change- in .Iupit.-r'< north 

 equatorial belt are attracting much attcnii 



at increase in width, which is now 

 nearly equal to that of the southern. This is more 

 remarkable as following a period of 



The cause of these changes in his atmo-pherc. the 

 sudden appcarnnce of spots (white, black, and 

 tinted), and of his immense belts ami their 



doubling, and projecting of marginal spurs 

 from them, often fantastic, and numerous other 

 phenomena must ever furnish fruitful question- 

 for speculation. Many of these details were seen on 

 Feb. 23. 1897, the faintest of which were seen only 

 by glimpses and vanished before they could be 



