Tag Archives: Astronomy

The Solar System’s Place In The Milky Way: Part 2

At the end of my previous post on this topic, I left you with a diagram of the solar system’s orientation and approximate trajectory in its orbit around the Milky Way galaxy. Below, we’re looking past the solar system towards the galactic core. The plane of the galaxy runs horizontally across the image, north is … Continue reading The Solar System’s Place In The Milky Way: Part 2

Annular Solar Eclipse

As this post goes live, it’s only a few days until an annular solar eclipse, like the one pictured above, will sweep across the Americas on 14 October 2023. Annular eclipses get their name from Latin anulus, “small ring”, which refers to the ring of sunlight that’s visible around the lunar disc, as shown in the image … Continue reading Annular Solar Eclipse

The Solar System’s Place In The Milky Way: Part 1

When I wrote recently about the pole stars of other planets, I was aware of one thing my sky maps didn’t show—the rotation poles of our galaxy. They weren’t really relevant to that discussion, but I’m now prompted to write a bit about the Milky Way galaxy, and our relationship to it, because I’ve just … Continue reading The Solar System’s Place In The Milky Way: Part 1

Pole Stars Of Other Planets?

When I wrote about Philip Latham’s juvenile science-fiction novel Missing Men Of Saturn (1953) recently, I pointed out that Latham had made an astronomically well-informed guess about a possible pole star for Saturn’s moon Titan. Latham (a professional astronomer) knew the orientation of Saturn’s rotation axis, which would have allowed him to deduce the location … Continue reading Pole Stars Of Other Planets?

Which Way Does Space Station V Rotate?

The “Phenomena” posts have been a little tied up with abstruse orbital mechanics and obscure revisions to lists of Scottish hills, of late, so I thought it might be time for a break from all that. So this post is about something superficially trivial in the film 2001: A Space Odyssey, which has mildly annoyed … Continue reading Which Way Does Space Station V Rotate?

Keplerian Orbital Elements

1. All planets move in elliptical orbits, with the sun at one focus.2. A line that connects a planet to the sun sweeps out equal areas in equal times.3. The square of the period of any planet is proportional to the cube of the semimajor axis of its orbit. Kepler’s Laws of Planetary Motion (formulated … Continue reading Keplerian Orbital Elements