Winter
Summer
This week’s major event has to be summer starting early on Saturday morning; the Solstice is on the 20th this year. So on Saturday night we begin the inexorably plunge back to midwinter. At the winter Solstice the North Pole is tilted 23 and a half degrees away from the sun and the sun is always over the horizon, at summer solstice it’s tilted 23.5 degrees the other way and the sun never sets. So the divergence between mid winter and midsummer is a massive 47 degrees which goes some way to explain the huge difference. At noon on Saturday the sun will be almost 80 degrees above the horizon in midwinter it barely scrapes 31, and if you imagine a compass Sunrise on the Summer solstice is diametrically opposite Sun Set on the winter solstice, and we get about 8 hours more daylight.
Another thing you may have noticed is that the length of the day isn’t changing much at all at the moment, the sun’s been setting at about 9:30 for more than a month. This is best explained if you think of the change in seasons as a pendulum. At the moment the days are still getting longer but on Saturday it all stops and goes in to reverse, the pendulum reaches the top of its swing. It starts falling back and accelerates to the bottom of its swing at the equinox in September when it changes by up to 4 minutes a day. It then starts decelerating to ward the winter solstice after which it then starts to fall away again toward the spring.
There are a number of distinct overlapping periods during the yearly cycle, in winter and Spring the days are lengthening, and shortening during Summer and Winter, during Autumn and Winter the nights are longer the days and vice versa in Spring and Summer. It’s a combination of two variables define the seasons, day compared to night and lengthening or shortening, which. In winter days are lengthening but nights are longer, spring days are lengthening but nights are shorter. In summer nights are lengthening but days are longer, and autumn gives us the worst of both worlds, longer and lengthening nights.
All this is pretty obvious if you think about it, and I’ve just used nearly 400 words to tell you summer starts early Saturday morning, but then again there’s not much else going on this week, unless you’re out and about between 3 and 4am.
During dawn Friday morning the crescent Moon hangs about 6° above Venus and Mars.
At the end of the official Midsummer Night, busy things are happening at dawn Sunday morning. About 45 minutes before, you can spot a very bright Venus in the east with faint little Mars just to its upper left. Using binoculars, look well left of Venus for the Pleiades, and look about 24° to Venus's lower left to pick up the thin crescent Moon and look lower right of the Moon for Mercury.
Jupiter is rising earlier all the time and now appears in the east before midnight and shines brightly in the south by dawn.
As Jupiter is in the ascent, we’re slowly loosing Saturn; it’s in the southwest at dusk and sinks lower in the west as the evening advances.
The vivid meteor shower on Tuesday night could have been one of three showers forecast: for June, meteor showers happen when the earth crosses the orbital path of a comet. If the comet happens to be there at the same time we get a mass extinction and nobody sees much of anything at all.
Another thing you may have noticed is that the length of the day isn’t changing much at all at the moment, the sun’s been setting at about 9:30 for more than a month. This is best explained if you think of the change in seasons as a pendulum. At the moment the days are still getting longer but on Saturday it all stops and goes in to reverse, the pendulum reaches the top of its swing. It starts falling back and accelerates to the bottom of its swing at the equinox in September when it changes by up to 4 minutes a day. It then starts decelerating to ward the winter solstice after which it then starts to fall away again toward the spring.
There are a number of distinct overlapping periods during the yearly cycle, in winter and Spring the days are lengthening, and shortening during Summer and Winter, during Autumn and Winter the nights are longer the days and vice versa in Spring and Summer. It’s a combination of two variables define the seasons, day compared to night and lengthening or shortening, which. In winter days are lengthening but nights are longer, spring days are lengthening but nights are shorter. In summer nights are lengthening but days are longer, and autumn gives us the worst of both worlds, longer and lengthening nights.
All this is pretty obvious if you think about it, and I’ve just used nearly 400 words to tell you summer starts early Saturday morning, but then again there’s not much else going on this week, unless you’re out and about between 3 and 4am.
During dawn Friday morning the crescent Moon hangs about 6° above Venus and Mars.
At the end of the official Midsummer Night, busy things are happening at dawn Sunday morning. About 45 minutes before, you can spot a very bright Venus in the east with faint little Mars just to its upper left. Using binoculars, look well left of Venus for the Pleiades, and look about 24° to Venus's lower left to pick up the thin crescent Moon and look lower right of the Moon for Mercury.
Jupiter is rising earlier all the time and now appears in the east before midnight and shines brightly in the south by dawn.
As Jupiter is in the ascent, we’re slowly loosing Saturn; it’s in the southwest at dusk and sinks lower in the west as the evening advances.
The vivid meteor shower on Tuesday night could have been one of three showers forecast: for June, meteor showers happen when the earth crosses the orbital path of a comet. If the comet happens to be there at the same time we get a mass extinction and nobody sees much of anything at all.
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