What is the time at which Earth's poles point at their greatest angle away from or toward the Sun?

Answer 1

Answer It is analogous to latitude on the Earth, but projected onto the sky. It is measured as degrees north of south of the celestial equator. "Declinations are measurements in relation to the Northern and Southern Hemispheres (Latitudes=Declinations) and how the planets appear to transit through the Northern and Southern Declinations."

Answer 2

The declination of the Sun changes moment to moment through the year, from 23.4 degrees north to 23.4 degrees south (approximately).

You can look up the declination of the Sun for any hour throughout the year from theOnline Nautical Almanac at the link below.

As of this moment, June 31, 2014 at 10:13 PM Pacific Daylight Time, the Sun is at declination 22 degrees, 02.5 minutes North.

Answer 3

The format of the question makes it sound like the Earth is tilting back and forth. It is not. The Earth is quite stable, spinning like a gyroscope, and the "precession", or variation, goes through one cycle every 26,000 years or so.

However, the Earth's axis is "tilted" with respect to the ecliptic, the plane of the Earth's orbit around the Sun. This angle, of about 23.5 degrees, doesn't change.

The north pole of the Earth is "farthest away" from the Sun on December 21, and closest to the Sun on June 21. (These dates may vary one day either way, depending on the cycle of leap years.)

Answer 4

The northern hemisphere is most tilted away from the sun within a day either way of December 22.

The Southern Hemisphere is most tilted away from the sun within a day either way of June 21.

Answer 5

23.5 degrees, on the first day of winter for the northernhemisphere.

23.5 degrees north of the celestial equator, on the first day of winter for the southern hemisphere.

Answer 6

The events are called the solstices (summer solstice and winter solstice). They occur on June 20/21 and December 21/22 each year. The June solstice is the summer solstice for the northern hemisphere and the winter solstice for the southern hemisphere.

At the June solstice, when the North Pole is at its greatest angle toward to the Sun, the Sun appears to circle directly over the Tropic of Cancer (about 23.5°N latitude). Any locations south of the Antarctic Circle (about 66.5°S latitude) will experience a day without any sun at all. (It is below the horizon for them.)

The reverse occurs at the December solstice (start of winter in the northern hemisphere) when the Sun appear to circle the Earth directly over the Tropic of Capricorn, and areas north of the Arctic Circle receive no sun for one or more days.

Answer 7

If you're in the northern Hemisphere, then the South Pole is inclined

toward the Sun at the winter solstice (~December 21)

If you're in the southern Hemisphere, then the North Pole is inclined

toward the sun when it is the coldest season. (the solstice is around June 21)

Answer 8

Neither. The northern hemisphere experiences its Summer solstice when the north pole points most toward the Sun and its Winter solstice when the south pole points most toward the Sun. Equinoxes come on the days exactly in the middle of the solstices so both poles are the same distance from the Sun.

Answer 9

At the northern Vernal Equinox, the two poles are equidistant from the Sun, with the North Pole on its trip towards getting closer to the Sun, while the South Pole is on its trip towards getting further away from the Sun.

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The Earth's poles point at an angle of about 23.26 degrees with respect to the plane of the Earth's orbit around the Sun. Right now, the North Pole points within one third of a degree towards Polaris, in Ursa Minor, but that slowly changes due to precession, with a period of 26,000 years.

That angle of tilt is, except for wobble, constant, and will be about 23.26 degrees all year round.

As the Earth orbits the Sun, the poles essentially become closer and further away from the sun, with a period of one year. This is what creates our seasons; Spring, Summer, Fall or Autumn, and Winter.

At the northern Vernal Equinox, the two poles are equidistant from the Sun, with the North Pole on its trip towards getting closer to the Sun, while the South Pole is on its trip towards getting further away from the Sun. This position reverses at the northern Autumnal Equinox, where the two poles are again equidistant, but the North Pole is travelling away from the Sun while the South Pole is travelling towards the Sun.

At the northern Summer Solstice, the North Pole is closest to the Sun, while the South Pole is furthest away, with the positions reversed at the northern Winter Solstice.

If you were to imagine a giant circle1, a clock face so to speak2, where the Sun is at the center and the Earth's orbit is the circle with a duration of one year, and your point of reference is from a direction above the North Pole, and perpendicular to the plane of the Earth's orbit, then the Earth would be travelling counter-clockwise around the Sun, the Vernal Equinox would occur at 3:00 O'Clock, and the North Pole would be slightly off-center of the dot of the Earth, towards the 6:00 O'Clock position.

The Summer Solstice would be at 12:00 O'Clock, the Autumnal Equinox would be at 9:00 O'Clock, and the Winter Solstice would be at 6:00 O'Clock. In every case, the North Pole maintains its off center position towards 6:00 O'Clock.

Merged in from the discussion:

There are two solstices during a given year, and there are two equinoxes. How you name them depends on your location. The northern summer solstice is the southern winter solstice, and the northern vernal equinox is the southern autumnal equinox. It would be perverse to expect people in the southern hemisphere to refer to their December solstice as the 'winter' solstice, for example; it marks the beginning of summer in the south.

Also; in reality earth has one 'axis'. It is the imaginary line around which the planet rotates. We are used to using the terms 'north pole' and 'south pole' conventionally to describe the points at which the axis exits the planet. The axis extends indefinitely far, northward and southward through space. The terms north and south are meaningful (and very useful) only with regard to our earth-bound view of the heavens. It is still one single, endlessly long line.

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1Strictly speaking, the Earth's orbit is not a circle - it is an ellipse

2Using the metaphor of the clock face is useful. Just remember that the period is one year, not 12 hours, and that the direction of rotation is counter-clockwise.

Answer 10

About 23.5 degrees in the opposite hemisphere from where you are. If you are in the northern hemisphere, the winter solstice happens when the Sun is at 23.5 degrees south, on about December 21.