Tag Archives: Astronomy

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

Why Does The Illuminated Side Of The Moon Sometimes Not Point At The Sun?

I took the above panoramic view, spanning something like 120 degrees, in a local park towards the end of last year. The sun was almost on the horizon to the southwest, at right of frame. The moon was well risen in the southeast, framed by the little red box in the image above. After taking … Continue reading Why Does The Illuminated Side Of The Moon Sometimes Not Point At The Sun?

We Are Stardust (Supplement)

I published my original “We Are Stardust” post some time ago, introducing the infographic above, which shows the cosmic origins of the chemical elements that make up our bodies, according to mass. At that time I concluded that Joni Mitchell should actually have sung “We are 90% stardust,” because that’s the proportion of our body … Continue reading We Are Stardust (Supplement)