![]() ![]() The equinoxes happen twice a year– once on 21 March and once on 23 September. The Equinox – either of the two times in a year when the Sun is right above the Equator and day and night are of equal length. This is marked by the longest and shortest days in the year (about 21 June and 22 December). The Solstice – either of the two times in a year when the Sun’s path is as far north or as far south from the Earth’s Equator. What’s the difference between a Solstice and an Equinox? Both are periodic solar events that happen on the same date every year. You’ll see that the difference lies in their very definitions. Original article on by Saanchi Biyani, a grade 5 student.įirst, here’s what they both mean – and you’ll see the difference. This article was provided to by Starry Night Education, the leader in space science curriculum solutions. This happens because the Earth's weather seasons actually lag a month or two behind the astronomical markers.Īnyway, enjoy the longer days and warmer weather. What’s more puzzling is why the "in between" markers are known as "midwinter" and "midsummer" when we all know that they both occur rather early in their named seasons. 22, the autumnal equinox, is the first day of fall. It’s quite clear why the vernal equinox has become known as the first day of spring, and why its equivalent when the sun moves south again on Sept. The seasons in the Southern Hemisphere are a mirror image of the ones in the north. Today is in fact the southern autumnal equinox, heading towards winter. What happens in the Southern Hemisphere when the sun crosses the equator into the northern sky? There the days grow shorter and the temperature drops. Stonehenge, in southern England, is one of the most spectacular examples of these equinox calendars. In some cases they built monuments to refine these measurements. They discovered clever ways of marking the rising and setting points of the sun. How did ancient peoples observe and measure the date of the vernal equinox, if it is blocked by the sunlit sky? Below and to the left is the distant dwarf planet Eris, hovering in the far reaches of the solar system. Above the sun and to its left (east) is Comet Pan-STARRS. Similarly, the summer equinox now puts the sun in Sagittarius, off the chart to the lower right, even though it gives its name to the "tropic of Capricorn." One of the differences between astronomy and astrology is that astronomy uses the current positions of the sun and planets in the sky, while astrology uses historical positions which have been out-of-date for thousands of years.īecause the sky has been darkened by the software, we can see how several planets are gathered on the far side (behind) the sun: Uranus, Mars, and Venus. Aries, where it used to lie, is now up in the upper left corner of the chart. The point at which the equator and the ecliptic cross, traditionally called "the first point in Aries," actually lies today in the constellation Pisces. The graphic shows the constellations in their modern positions. Also the sun's rays will be striking the northern hemisphere from a more acute angle, so that the same amount of solar radiation is concentrated in a smaller area, amplifying the heating factor. More hours of sun means more warming by the sun, so the days will also get warmer. From now until the summer solstice on June 21, the days will gradually get longer because the sun will be higher in the sky, giving more hours of daylight. ![]()
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