history of hopes

1686

Bernard le Bovier de Fontenelle (1657-1757) publishes his Entretiens sur la pluralité des mondes ("Conversations on the plurality of worlds") in which he discusses life on the planets.  e.g. Venusians are little black people, scorched with the Sun, witty, full of fire, very amorous... and Jovians are Phlegmatic... people who know not what it is to laugh, they take a day's time to answer the least question.    [TELD p.19].

(Fontenelle died just about a month short of his 100th birthday.)

1785

According to TELD p109, Samuel Ellsworth, in his almanac, describes (presumably under the influence of mythology) the inhabitants of Mercury as:

   ...very sprightly, small in body, maintaining the upright posture of men, much given to talking, eloquent of speech, good lawyers and pettifoggers...

1787

In July 1787, Dr John Elliot, apothecary and scientist, assaulted Miss Mary Boydell in the streets of London. Elliotś defenders sought his acquittal on the grounds of insanity, and cited as proof a paper in which he alleged the existence of intelligent life on the surface of the sun. [John Elliott and the inhabited Sun (1993)]

1795

William Herschel's paper in the Royal Society's Philosophical Transactions in which he theorized that the sun consists of a cool, solid, spherical interior above which floats an opaque layer of clouds that simultaneously reflects the rays of the glowing exterior region and shields the interior region from excessive heat and light.  "The sun... appears to be nothing else than a very eminent, large, and lucid planet, evidently the first, or in strictness of speaking, the only primary one of our system...  Its similarity to the other globes of the solar system... leads us to suppose that it is most probably... inhabited... by beings whose organs are adapted to the peculiar circumstances of that vast globe."  [TELD p67]

1798

Wordsworth composes Peter Bell, A Tale (it is published in 1819) which refers in particular to Martians and Saturnians, and also to Mercurians and Jovians:

Up goes my Boat among the stars
Through many a breathless field of light,
Through many a long blue field of ether,
Leaving ten thousand stars beneath her:
Up goes my little Boat so bright!
The Crab, the Scorpion, and the Bull--
We pry among them all; have shot
High o'er the red-haired race of Mars,
Covered from top to toe with scars;
Such company I like it not!
The towns in Saturn are decayed,
And melancholy Spectres throng them;--
The Pleiads, that appear to kiss
Each other in the vast abyss,
With joy I sail among them.
Swift Mercury resounds with mirth,
Great Jove is full of stately bowers...    

1808

Schröter's Kronographische Fragmente maintains that Saturn's ring system is a solid body, studded here and there with mountains, and possessing its own atmosphere [TELDp72].

1828

David Milne in his Essay on Comets speculates on the possibility of cometarian life:

Comets may be the residence of beings widely different from those which fall within the narrow sphere of human observation.  What though these beings, from the peculiarities of their situation, be endowed with neither lungs, nor eyes, nor the feelings which afford the sensations of heat and cold, like our bodily organs?
                                                                                       [TELDp222]

1830

Sir Humphrey Davy in his posthumous Consolations in Travel (partly a record of his dreams) sees Saturnians as intellectually superior to Earthlings; they swim in their planet's atmosphere with "systems of locomotion similar to those of the morse or sea-horse, but I saw with great surprise that they moved from place to place by six extremely thin membranes which they used as wings"; they "possess many modes of perception of which we are wholly ignorant".
    In a letter to Lady Davy the author described the book as containing "certain truths that cannot be recovered if they are lost, and which I am convinced will be extremely useful"...     [TELDp223]

1832

Ralph Waldo Emerson delivers an extraordinary sermon on 27th May, entitled "Astronomy", discussed on pages 235-6 of TELD (1986):

...Emerson begins by noting that both nature and Scripture are viewed as coming from God...  Astronomy has corrected Man's tendency to view God in anthropomorphic ways...  Man could not breathe on the moon or walk on Jupiter, nor could his blood circulate on Uranus; yet God has populated these bodies with beings possessing "perhaps far more excellent endowments than he has granted to mankind..."    

1834

Alexander Copland in The Existence of Other Worlds predicts that lunar life will soon be verified "by actual sight of the natives or their works..."   [TELD p229]

1851

In the first volume of his Système de politique positive, Auguste Comte laments the public's recent "mad infatuation" on the subject of the "alleged" discovery of Neptune,

...which, even if real, would not be of interest to anyone except the inhabitants of Uranus.

This is quoted in TELD (p.255), without any suggestion that Comte was being ironic about the existence of Uranians.  (Ironic or not, it seems odd, not to say a bit crazy, for a philosopher to ridicule interest in astronomy.)

1856

Regarding the idea of the habitability of the moon, or rather of part of it:

In 1856, Peter Andreas Hansen (1795-1874), a prominent mathematical astronomer, published a paper in the Royal Astronomical Society Memoirs in which he accounted for certain discrepancies between lunar observation and theory by hypothesizing that the center of gravity of the moon is about thirty miles more distant from the earth than the moon's center of figure.  This claim implied that any water and air on the moon would be drawn to its remote side, where the gravitation field would be strongest...   [TELD p219]

1869

The Frenchman Charles Cros (1846-88) proposes a method for interplanetary signalling: rays from electric lights could be focused by parabolic mirrors so as to be visible to inhabitants of Mars or Venus, if such exist and possess telescopic means. 
                       [TELD (1986), p394]

1872

English edition of Le ciel (1864) by French science writer Amédée Guillemin (1826-93), in which
                ...without much discussion he accepts life on Mercury, Mars, Jupiter and Saturn.  The question of solar (p.53) and lunar (p.145) life he leaves largely open...
                                                                               [TELD (1986) p470]

1878

Asaph Hall, in his paper on his discovery of the moons of Mars the previous year, also remarks on the issue of communication with our Moon: 
   ...it appears that the proposition of a German astronomer to establish on the plains of Siberia a system of fire signals for communicating with the inhabitants of the Moon is by no means a chimerical project...     [TELD (1986) p481]

1886

Tennyson suggests pleasant possibilities for the planet Venus:

Venus near her! smiling downward at this earthlier earth of ours,
Closer on the Sun, perhaps a world of never fading flowers.

Hesper, whom the poet call’d the Bringer home of all good things.
All good things may move in Hesper, perfect peoples, perfect kings.

[Locksley Hall: Sixty Years After]

1889

Schiaparelli on p.141 of his Sulla rotazione di Mercurio ("On the rotation of Mercury") regards life as possible on the innermost planet, which
...received light and heat from the sun, not only in greater amount but in a different manner than the earth; and where life, if so be life exists there, finds conditions so different from those to which we are accustomed that we can scarcely imagine them.  The perpetual presence of the sun almost vertically above certain regions, and its perpetual absence from other regions...  should produce an atmospheric circulation which is at the same time stronger, more rapid, and more regular than that which sows the elements of life on the earth; and that on this account it may come about that an equilibrium of temperature is produced quite as complete as ours, and possibly even more so...    
                                                                                                   [TELD p484-5]

1892

William Henry Pickering, observing Mars at opposition with a 13-inch refractor at Harvard's southern station 8100 feet high in the Peruvian Andes, cabled his observations to the New York Herald:  "[Have] discovered forty small lakes in Mars..." 
                                                                         [The Immortal Fire Within (1995), p237]

1895

In a paper of this year Schiaparelli speculates that Martian engineers may have built dykes at various levels along the slopes of the shallow valleys through which their waterways run.  When the spring inundations begin, the "Minister of Agriculture orders the opening of the most elevated sluices and fills the upper canals with water...  The irrigation then spreads to the two (lower) lateral zones..., the valley changes color in these two lateral zones, and the terrestrial astronomer perceives a gemination."  Gradually the water is released into the lower portions of the valley, fertilizing the lowest region of the valley and producing a single "canal" appearance...      [TELD p515]

In the same paper, Schiaparelli continues his attempts to deduce possibilities about Martian society from his observations:

   The institution of a collective socialism might indeed result from a parallel community of interests and of a universal solidarity among the citizens, a veritable phalanstery which can be considered a paradise of societies.  One may also imagine a great federation of humanity in which each valley constitutes an independent state.  The interests of all are not distinguished from the other; the mathematical sciences, meteorology, physics, hydrography, and the art of construction are certainly developed to a high degree of perfection; international conflicts and wars are unknown; all the intellectual efforts which, among the insane inhabitants of a neighboring world are consumed in mutually destroying each other, are [on Mars] unanimously directed against the common eney, the difficulty which penurious nature opposes at each step.    

1900

The Guzman Prize (Prix Pierre Guzman) was announced by the French Academy of Sciences: 100,000 francs to be awarded to the first person to establish communication with a celestial body other than Mars - the Red Planet being excluded because it was thought that to make contact with its inhabitants would be too easy.

1904

How gets on the photography...  of Mars for the next opposition?  We must secure some canals to confound the skeptics...        [Lowell and Mars (1976), p177]

1906

That Mars is inhabited by beings of some sort or other we may consider as certain as it is uncertain what those beings may be.  Girdling their globe and stretching from pole to pole, the Martian canal system not only embraces their whole world, but is an organized entity.  Each canal joins another, which in turn connects with a third, and so on over the entire surface of the planet.  This continuity of construction posits a community of interest.  Now, when we consider that though not so large as the Earth the world of Mars is one of 4200 miles diameter and therefore containing something like 212,000.000 of square miles [sic], the unity of the process acquires considerable significance.  The supposed vast enterprises of the Earth look small beside it.  None of them but become local in comparison, gigantic as they seem to us to be.
   The first thing that is forced on us in conclusion is the necessarily intelligent and non-bellicose character of the community which could thus act as a unit throughout its globe.  War is a survival among us from savage times and affects now chiefly the boyish and unthinking element of the nation.  The wisest realize that there are better ways for practicing heroism and other and more certain ends of insuring the survival of the fittest.  It is something people outgrow.  But whether they consciously practice peace or not, nature in its evolution eventually practices it for them, and after enough of the inhabitants of a globe have killed each other off, the remainder must find it more advantageous to work together for the common good.  Whether increasing common sense or increasing necessity was the spur that drove the Martians to this eminently sagacious state we cannot say, but it is certain that reached it they have, and equally certain that if they had not they must all die.  When a planet has attained to the age of advancing decrepitude, and the remnant of its water supply resides simply in its polar caps, these can only be effectively tapped for the benefit of the inhabitants when arctic and equatorial peoples are at one...
        
                                               [Mars and its Canals (1906), final chapter]

1918

...Venus is no doubt covered with swamps, corresponding to those on Earth in which the coal deposits were formed, except that they are about 30°C warmer...  The powerful air-currents in the highest strata of the atmosphere equalize the temperature difference between poles and equator almost completely, so that a uniform climate exists all over the planet...  The temperature on Venus is not so high as to prevent a luxurious vegetation.  The constantly uniform climatic conditions which exist everywhere result in an entire absence of adaptation to changing exterior conditions.  Only low forms of life are therefore represented, most no doubt belonging to the vegetable kingdom, and the organisms are of nearly the same kind all over the planet.  The vegetation processes are greatly accelerated by the high temperature.  Therefore, the lifetime of organisms is probably short...  later, the temperature will sink, the dense clouds and gloom disperse, and some time, perhaps not before life on Earth has reverted to its simpler form or even become extinct, a flora and fauna will appear, and Venus will then indeed be the "Heavenly Queen" of Babylonian fame, not because of her radiant lustre alone, but as the dwelling-place of the highest beings in our Solar System."  [The Destinies of the Stars (1918)]

1923

...the December 12, 1923 New York Times carried an article captioned "Flammarion Predicts Talking with Mars."  The message by which this was to be accomplished: telepathic waves.

[TELD p386]

1950

Patrick Moore in his autobiography describes an incident shortly before a Sky At Night broadcast on the question of Martian life, which is suggestive about the garbled hopes of journalists:
   ...At a public lecture just before our television programme I stated that "on Mars there may be lowly organisms, but nothing so advanced as a cabbage."  One local newspaper gave a rather inaccurate report: "Astronomer claims that the nearest approach to Earth-type life on Mars is the growth of large cauliflowers."              [Eighty Not Out (2003), p102]

1957

In the second edition of his Flight Into Space, J N Leonard writes (p.154) - contradicting himself somewhat in the first two sentences, but overall expressing optimism as to the possibilities -

   If intelligent beings do exist on Mars, they are certainly not at all like the dramatis personae of science fiction.  They are just as likely to be disembodied brains like those coldly intelligent creatures in H.G.Wells' War of the Worlds.  They may even be clever fungi with sedentary central intelligences directing the operations of far-reaching food-gathering organs.  Not enough is known about Mars to give even the sketchiest idea of what its inhabitants are like and how they live - or whether they exist at all above the level of lichens or algae.    

1958

Question number 182 in 1001 Questions Answered About Astronomy is asked and answered as follows:

182.  What is the green on Mars?  Probably vegetation.  There is a seasonal change in the colour of the green regions in general, which follows to some extent the pattern of the seasonal colour change in vegetation on the Earth.  The green areas on Mars are faint and delicate during the Martian spring; they grow much darker and, in some cases, almost a blue-green in the Martian summer; yellow and brown in the autumn, and a rather lifeless grey in the winter.  The green regions are probably not covered with grass or trees, because they do not show the same sort of reflection of light that is produced by a chlorophyll plant.  The vegetation, if such it is, is likely to be a sort of lichen which can grow in little or no soil, with a minimum of moisture and can withstand extremely cold temperatures.  There is a theory, too, that the green substance is volcanic dust, whose drifting and shifting in the very light breezes that are all the rare atmosphere of Mars could produce, accounts for the colour change; however, few authorities support this idea.    

1959

   Apart from its phases, there is little to be seen on Venus...  Some astronomers think that its surface is almost completely covered with sea...     
                                             [Our World in Space and Time, p.168]

1960

   ...As we have seen, most authorities now seem to be convinced that there is some form of low-grade plant life or vegetation living on Mars' surface...  [Nine Planets, p165]
After going on to argue that even the low-grade vegetation could not have evolved under the harsh Martian conditions of our time, but must have survived from an earlier epoch, the author swings into optimism, with paradoxical ingenuity - see the passage I have emphasized in bold:
   ...So if we accept the presence of plant life on Mars today, we have no choice but to agree that Mars is old, that is has changed radically and violently from the surface conditions that prevailed in the past, and that the life there now is all that is left of an extensive evolutionary progression on a dying planet.  And if we accept these things, then we must accept the fact that intelligent life must have developed there - if intelligence is indeed a natural, inevitable step in the cosmic cycle of the Universe.
A bit later he suggests that the Martians may have left their native planet in order to find a more comfortable home among the stars!
   Alan E Nourse (1928-92) was, as far as I am aware, a fairly well respected science writer, as well as a science-fiction writer known for the magnificent Brightside Crossing - one of the few great tales set on Mercury.