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7

You are mixing the rotation of the body around a barycenter with its moons, and the rotation of the body around its own center. For a bound rotation like Pluto and Charon both have to have the same rotation period - yet both have to be present. Thus Pluto's axis of rotation of course intersects its surface - it rotates around its own axis at exactly the same ...


5

I'll just add a supplement to @planetmaker's answer. As long as a body is distinct and not connected to anything else, it will have a center of mass. If the body is roughly spherical its center of mass will be near it's middle. The body's rotational axis by definition passes through its center of mass, and is parallel to it's own angular momentum vector. If ...


3

Let my try to stretch the analogy to anticyclonic tornados: The vast majority of all tornados move cyclonic, i.e. counterclockwise on the Northern Hemnisphere of our blue planet. There is e.g. a publication on anticyclonic tornados by Howard Bluestein et. al. which says: It is also possible that the source of vorticity in the anticyclonic tornadoes is not ...


3

I have made an interactive simulation of Uranus and its seasons at https://ecliptiqc.ca/UranusEN.php. Playing with it, I get the north pole of Uranus pointing sunwards in early 1946 (my steps are 6 months, so I can’t be more precise for now). The actual date may be slightly different, as I use a “fixed” orbit instead of the osculating elements, but it would ...


2

According to JPL HORIZONS, the sub-solar latitude on Uranus has maxima on 1946-04-03 and 2030-04-11, and Uranus's heliocentric J2000 ecliptic longitude at those times is 77.54°. If I put the pole coordinates from the IAU WGCCRE report through the NED coordinate calculator, I get a J2000 ecliptic longitude of 77.65° for Uranus's south pole. The solstice ...


1

That's a timelaps video, most likely created from a sequence of photos. It's easy to choose sensitivity and ISO settings on normal cameras such that the night sky at the darkest night is over-exposed. The moon light looks like sunlight - as it simply is reflected sunlight. E.g. see https://cloud.planetmaker.de/index.php/s/yJ7AXWG4dEC6csW - it's a an exposure ...


1

Why does the Moon never set in Svalbard, Norway? Source As can be deduced from the diagram or knowing that the Moon's orbit is inclined by only 5 degrees with respect to the ecliptic while the Earth's axis is inclined by more than 23 degrees, the moon can not always be above the horizon, nor always be below it. Over the course of about 20 years all ...


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