Thereby Hangs a Tail


Venus’ ionosphere under normal solar wind pressure (left) and extremely low solar wind pressure (right). The yellow lines indicate the contours of the solar magnetic field. © ESA/Wei et alii 2012.


Dec 17, 2014

Direct statements concerning dramatic changes in the appearance of planets are few and far between in ancient sources.

A classic example is a fragment from the obscure Greek astronomer Castor of Rhodes (1st century BCE), as cited by his contemporary, the Roman grammarian Marcus Terrentius Varro, who was in turn cited by the church father Augustine of Hippo (354-430 CE). According to this tantalisingly brief passage, the planet Venus once “changed its colour, size, shape and course, a thing which has never happened before or since.” This information, frequently considered in catastrophist theories, presents quite a puzzle.

A conservative approach would be to assume that the observation of Venus’ erratic presentation was due to some change in the earth’s own properties. After all, the ‘green flash’ and the ‘blue flash’ frequently seen on Venus, like the twinkling of all celestial bodies, is caused by variations in the earth’s atmosphere. However, whereas these might shed light on alterations in Venus’ apparent colour and possibly size, they do not affect its shape and orbit. A temporary jolt in the earth’s motion, without any actual change in Venus, is an equally unlikely solution, because this would produce simultaneous changes in the positions of all other stars and planets – which is not what Castor reported.

The German philologist Johann Gottlieb Radlof (1775-1827/1829), writing in 1823, may have been the first to advocate a straightforward, literal take on the account. Other catastrophists, including Alexander Braghine (1878-1942) and Immanuel Velikovsky (1895-1979), followed suit: apparently, Venus was once observed to have changed its orbit. Par for the course, for this interpretation overlooks a crucial aspect of Augustine’s testimony, which is rarely – if ever – mentioned: “the altered course of Venus did not long continue, but the usual course was resumed”. If the planet’s features returned to the status quo ante within the time frame of a few years at most, a true modification of its orbit is of course highly implausible.

Unlike the situation on the earth, Venus’ native magnetic field is almost negligible. Its magnetosphere is induced by the enveloping solar wind. Satellite data show that the planet at times sports a magnetotail which can assume enormous proportions, ‘fluttering’ in the solar wind. The precise conditions and variables involved are the subject of on-going research. Could the assumption that Venus’ tail, on an exceptional occasion, glowed in visible light be on the right track? Short-lived visibility of Venus’ appendage could account at once for all changes mentioned in Castor’s report: the tail would have its own colour, appear to enlarge Venus, change it from a dot to a streak of light and, because of its drifting in the solar wind, seem to modify the planet’s orbit.

Presumably, such an event would have been the result of a solar superstorm, the like of which has not been seen in millennia. A magnetic storm of such intensity would likely affect the earth as well and it may not be coincidental that, according to the otherwise unknown mathematicians Adrastus of Cyzicus and Dio of Naples, cited by Augustine in the same context, the portent “happened in the reign of Ogygus”, that is to say, concomitantly with the legendary flood of Ogyges. Although the physical relationship between a solar superstorm and a terrestrial flood is not easily explained and the date of the legendary Ogyges is a vexing subject in its own right, the correlation is bound to be relevant. This was pointed out as early as 1684, by the English theologian and royal chaplain Thomas Burnet (c. 1635? – 1715):

“This is a great presumption that she suffer’d her dissolution about the same time that our Earth did. I do not know that any such thing is recorded concerning any of the other Planets, but the body of Mars looks very rugged, broken, and much disorder’d.”

With these sentiments, written just a few years after Isaac Newton had presented his theory of gravity, Burnet qualifies as the earliest known planetary catastrophist.

Rens Van Der Sluijs

Print Friendly