The more common astronomical sign for the planet Uranus is

"Uranus has two astronomical symbols. The first to be proposed

was suggested by Lalande in 1784. In a letter to Herschel, Lalande described it as un globe surmonté par la première lettre de votre nom ('a globe surmounted by the first letter of your surname').

A later proposal ... is a hybrid of the symbols for Mars and the Sun because Uranus was the Sky in Greek mythology, which was thought to be dominated by the combined powers of the Sun and Mars ..." (Wikipedia)

I had tried to understand why the vero glyph in position 378 (equal to the synodic cycle of Saturn) looked somewhat similar to our sign for Mars. First I assumed that the stringlike arrow of our Mars sign according to the idiom of rongorongo had to be broader in order to indicate the wood of a spear.

Then there remained to be explained why the arrow was pointing straight up instead of 45º (360º / 8) to the right. But I could not arrive at any reasonable explanation.

In the Babylonian zodiac the sign for the Sun - close to that of Saturn and where the 4th quarter is beginning - probably represents the nighttime Sun. Similarly the Mars symbol has been turned away from its expected orientation. The latter could mean Mars is not present (as yet).

Taken together with the new information of Sky being dominated by the combined powers of Sun and Mars, it seems reasonable to assume these nighttime signs are located to show where Sky is.

The planet Uranus has now opened the case. Its symbol has an arrow which is pointing straight up. But the central dot cannot be described according to the grammar of rongorongo, where only outlines can be drawn.

In the Babylonian zodiac Mercury was placed between Furrow and Frond, ignoring the fact that a planet does not stand still. Likewise should then Uranus be possible to locate at a distinct place in the star chart.

I suspected the given date: the 25th of September, 1756, when the 'star' was first observed (according to modern descriptions), could have been adjusted in order to give the position of Uranus as 'not far away' from Scheat Aquarii.

25 * 9 = 225 (= 15 * 15).

The astrologers must have had a busy time readjusting all their parameters when Uranus was discovered.

But in a way it would not have been very difficult, because there was a free space pointed at by the Babylonians - those 52 nights when the Deluge covered all 'Land'. Possibly they too had discovered Uranus, but dismissed the object as too difficult to incorporate in their cosmos.

Measuring time-space by the 8 'arms of the Octopus', there was 1 tentacle missing, the 8th and last. 7 / 8 * 360 = 315 = 314 + 1. The lost arm was where time was rejuvenated, therefore the addition. This could have been alluded to by the probable number of nights on the G tablet, viz. 1½ * 314 + 1.

Speculations aside, those who created the rongorongo tablets may have known of the (re)discovery of Uranus and when that had happened. From there the rest could be calculated.

And then it would have been possible to compare Easter Island to this far away planet, equally difficult to find again after having been lost. Manuscript E (p. 12) according to Barthel: