30.9.09

Knitting at the Lib Dem Conference

Stars spinning around Polaris



It's all much the same this week as you may well have anticipated. Jupiter is still blazing away in the southern sky very close to the waxing moon until it sets at about 1am, just as Mars becomes visible in the east sou eastern sky. Venus is moving further away from Mars toward the sun and shines very brightly in the east 2 hours before dawn in the east from about 5 am. Where’s it joined by Mercury and then Saturn around 6:30 am shortly before sunrise. Venus will be easily visible for early risers in the east but Mercury and Saturn are pretty well reserved for those of us on Tresco and St Martins because they are so low on the horizon they’ll be obscured by hills. But both are to close to the rising sun to be worth a look at the moment. But there’s a guide on the blog if you’re grimly determined.

September and early October are very much a transient time for the stars. The familiar winter constellations are not quite there yet. The Pleiades and the V of Taurus with its giant bright red malignant eye Aldebaran is well up in the east by 11, but it’s another month until my favorite constellation Orion is around much before midnight. And then Orion will be with us until late April when the summer stars are beginning to appear. The whole thing is centered on Polaris the pole star which the whole sky seems to revolve around including the moon and the sun, this is because the pole star hangs almost directly above the North Pole and doesn’t appear to move. It is in effect in line with the imaginary axle the earth spins on. With a long exposure the stars weave a circle of light around Polaris, the North Star, and the stars near Polaris will always be in the sky. The Northern constellations like the plough or Cassiopeia are there in the sky every night and during the day, if they could be seen. Orion and Taurus even the sun also appear to revolve around Polaris but the circle they carve goes way over the horizon so they come and go. And with the earth spinning at 23.5 degrees the southern horizon shifts up and down by twice that between December and June, which is about a ¼ of the sky, which is why stars on the North and Southern horizons only appear at certain times of the year. I’ve completely confused my self now but sadly theirs more to come. Many constellations are over the horizon at some point every day but for half the year they will be up with the sun, the summer zodiac constellations are never seen in the summer, for example Taurus and Gemini are only just now putting in an appearance, now. And that’s enough of that especially at 7:30 am. But why should I care, I’m asleep, but probably dreaming about it.

Moving on, we have the harvest full moon on Saturday, and when the full moon comes this early in the month it means we’ll have a blue moon soon, October and November just miss it but we have the second full moon in December on the 31st, so we have a blue moon on New Years Eve which is as good a reason as any to celebrate I suppose.

And finally for the 55th time theirs a new definitive answer to whether there are more stars in the universe than there are grains of sand on the earth. A bunch of mathematicians from Hawaii, presumably to effete to surf have determined that there are 1 with 19 zeros grains of sand on the earth whilst there are 1 with 22 zeros stars, I read how they worked it out but its pretty tedious. But sand does have the last laugh because it only a thousand times more and there must be billions of planets out there full of sand, so in the final analysis sand wins hands down.

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