This morning the sun was eclipsed by the moon, which passed directly in front of the sun...
Here at latitude 52, the sky did not become significantly darker; just strange.
The light had an almost X ray quality to it.
Colour was bleached out of the land, and shadows were more obvious and wrong.
Even when 90% of the sun is covered by the moon, we don't get total darkness. The experience of a rapid onset of a night, a fall in temperature, silent birds and various optical illusions such as rainbow-tinted clouds and seeing clouds appearing to drop towards the earth at the time of maximum eclipse happened further north...
The experience of a 90% eclipse is unsettling, but without welding glass I would not be able to see what was happening in the sky even if I squinted. I may have seen something biting the sun away if thin cloud had been in the way, But cloud is not a good or reliable filter.
This means that even when a total eclipse happens -and they don't happen very often, and over land even less - they are not very obvious....
Lunar eclipses happen frequently, and can be looked at. But total eclipses -the only ones that are really noticeable- are still quite rare.
Today the equinox takes place specifically at 10:45 pm, and it is a descending node. As the equinox is something that is measured from earth, the time the sun crosses the equator (the definition of equinox) depends upon your latitude.
Less specifically it is 'the equinox' today, everywhere. Today the sun travels across the sky 'on the celestial equator'; rising in the east, at azimuth 90 degrees, setting at the west, azimuth 270 degrees.
Tomorrow the sun rises at 89 az, and sets at 272
On Sunday rise at 88 az and set at 272.
I'm not one for precision; by the time a person has factored in parallax and refraction, a change of one or two degrees in a rising or setting position isn't so much. The most interesting thing about the equinox is what happens to shadows. Because today is the best day for creating an east - west line.
If you mark the tip of a shadow through out the day, the marks will be in a straight line, the east - west line.
And finally..
Super moon.
Means that the moon is slightly bigger because it is closer to us...discuss.
When a Full or new moon is closer than 360,000 kilometers (ca. 223,694 miles) to us (at perigee) it is considered a supermoon. Paradoxically the biggest moon is not the closest moon. The size the moon appears to be is mostly an optical illusion; the moon appears biggest when it is low in the sky the lowest moons occur when the ecliptic is at its lowest and the moon is 5 degrees below the ecliptic. Basically when the moon is rising from Sagittarius / Scorpio and it is below the ecliptic, that will be the biggest moon according to your eyes.
Here at latitude 52, the sky did not become significantly darker; just strange.
The light had an almost X ray quality to it.
Colour was bleached out of the land, and shadows were more obvious and wrong.
Even when 90% of the sun is covered by the moon, we don't get total darkness. The experience of a rapid onset of a night, a fall in temperature, silent birds and various optical illusions such as rainbow-tinted clouds and seeing clouds appearing to drop towards the earth at the time of maximum eclipse happened further north...
The experience of a 90% eclipse is unsettling, but without welding glass I would not be able to see what was happening in the sky even if I squinted. I may have seen something biting the sun away if thin cloud had been in the way, But cloud is not a good or reliable filter.
This means that even when a total eclipse happens -and they don't happen very often, and over land even less - they are not very obvious....
Lunar eclipses happen frequently, and can be looked at. But total eclipses -the only ones that are really noticeable- are still quite rare.
- The next lunar total eclipse (at lat 52) is Monday, September 28th, 2015 at 1:13am.
Today the equinox takes place specifically at 10:45 pm, and it is a descending node. As the equinox is something that is measured from earth, the time the sun crosses the equator (the definition of equinox) depends upon your latitude.
Less specifically it is 'the equinox' today, everywhere. Today the sun travels across the sky 'on the celestial equator'; rising in the east, at azimuth 90 degrees, setting at the west, azimuth 270 degrees.
*The elevation angle of the sun at midday today = 90 - your latitude.The rise and set azimuths at the equinox change quickly compared to the solstice positions. You have about three days to see the sun in its equinox positions, but only one day - today - is accurate.
Tomorrow the sun rises at 89 az, and sets at 272
On Sunday rise at 88 az and set at 272.
I'm not one for precision; by the time a person has factored in parallax and refraction, a change of one or two degrees in a rising or setting position isn't so much. The most interesting thing about the equinox is what happens to shadows. Because today is the best day for creating an east - west line.
If you mark the tip of a shadow through out the day, the marks will be in a straight line, the east - west line.
And finally..
Super moon.
Means that the moon is slightly bigger because it is closer to us...discuss.
When a Full or new moon is closer than 360,000 kilometers (ca. 223,694 miles) to us (at perigee) it is considered a supermoon. Paradoxically the biggest moon is not the closest moon. The size the moon appears to be is mostly an optical illusion; the moon appears biggest when it is low in the sky the lowest moons occur when the ecliptic is at its lowest and the moon is 5 degrees below the ecliptic. Basically when the moon is rising from Sagittarius / Scorpio and it is below the ecliptic, that will be the biggest moon according to your eyes.
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