Top of post: June sunrise in Sea Bright, New Jersey, via Steve Scanlon Photography.
At mid-northern latitudes in the Northern Hemisphere, your earliest sunrises of the year happen around mid-June, despite the fact that the summer solstice – the year’s longest day – is still about a week away. And if you live at middle latitudes in the Southern Hemisphere, your earliest sunsets take place around now, even though the winter solstice – your shortest day – isn’t for another week.
For the Northern Hemisphere: For those of you who are privileged to be outdoors before one of these early sunrises, you’ll find some of the most beautiful dawn twilights of the year.
For the Southern Hemisphere: If you’re someone who relishes the day’s light, as many do, you might be glad of the sunsets will soon be shifting later!
The exact date of earliest sunrise (and earliest sunset) varies with latitude. At 40o north latitude – the latitude of, say, Philadelphia in Pennsylvania – the earliest sunrise of the year will happen on June 14. For that same latitude, the latest sunset of the year will fall on or near June 27. Meanwhile, the longest day of the year – the day containing the greatest amount of daylight, overall – comes on the solstice on June 21.
So it is for other Northern Hemisphere latitudes. The dates of earliest sunrise and latest sunset don’t coincide exactly with the solstice. Appreciably south of Philadelphia’s latitude, the earliest sunrise has already come and gone (in late May or early June) and the latest sunset occurs at a later date (sometimes as late as July). In Hawaii, for instance, the earliest sunrise precedes the June solstice by about 2 weeks, and the latest sunset comes about 2 weeks after. Farther north, the earliest sunrise and latest sunset happen closer to the June solstice. Check it out at your latitude, using links on our almanac page.
The earliest sunrises come before the summer solstice because the day is more than 24 hours long at this time of the year. In the Southern Hemisphere, the earliest sunsets of the year come before the winter solstice for the same reason.
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See full size | Sunrise over Currituck, North Carolina. Credit: GregDiesel Landscape Photography
In June, the day (as measured by successive returns of the midday sun) is nearly 1/4 minute longer than 24 hours. Hence, the midday sun (solar noon) comes later by the clock on the June solstice than it does one week before. Therefore, the sunrise and sunset times also come later by the clock, as the tables below help to explain.
For Philadelphia (40o north latitude)
| Date | Sunrise | Midday (Solar Noon) | Sunset | Daylight Hours |
| June 14 | 5:31 a.m. | 1:00 p.m. | 8:31 p.m. | 14h 59m 15s |
| June 21 | 5:32 a.m. | 1:02 p.m. | 8:32 p.m. | 15h 00m 35s |
For Valdivia, Chile (40o south latitude)
| Date | Sunrise | Midday (Solar Noon) | Sunset | Daylight Hours |
| June 14 | 8:12 a.m. | 12:53 p.m. | 5:34 p.m. | 9h 21m 56s |
| June 21 | 8:14 a.m. | 12:54 p.m. | 5:35 p.m. | 9h 20m 39s |
Source: timeanddate.com
The primary reason for the earliest sunrise preceding the summer solstice (and the earliest sunset preceding the winter solstice) is the inclination of the Earth’s rotational axis. The earliest sunrise or sunset would take place before the solstice even if the Earth went around the sun in a circular orbit.
However, the Earth’s elliptical orbit does affect the severity of the phenomenon. At the June solstice, Earth in its orbit is rather close to aphelion – its farthest point from the sun – which lessens the effect. At the December solstice, Earth is rather close to perihelion – its closest point to the sun – which accentuates it.
At middle latitudes, the earliest sunrise/sunset comes about one week before the June summer/winter solstice, and the latest sunset/sunrise about one week after the June solstice.
Yet, at the other end of the year, at middle latitudes, the earliest sunset/sunrise comes about two weeks before the December winter/summer solstice, and the latest sunrise/sunset about two weeks after the December solstice.
Early sunrise in Sweden via Per Ola Wiberg
Early sunrise by Flickr user Raffee
Bottom line: Are you an early riser? If so – if you live in the Northern Hemisphere – you might know your earliest sunrises of the year are happening now. Southern Hemisphere? Your earliest sunsets are around now.
EarthSky astronomy kits are perfect for beginners. Order today from the EarthSky store
Donate: Your support means the world to us
from EarthSky https://ift.tt/1lM9VQO
Top of post: June sunrise in Sea Bright, New Jersey, via Steve Scanlon Photography.
At mid-northern latitudes in the Northern Hemisphere, your earliest sunrises of the year happen around mid-June, despite the fact that the summer solstice – the year’s longest day – is still about a week away. And if you live at middle latitudes in the Southern Hemisphere, your earliest sunsets take place around now, even though the winter solstice – your shortest day – isn’t for another week.
For the Northern Hemisphere: For those of you who are privileged to be outdoors before one of these early sunrises, you’ll find some of the most beautiful dawn twilights of the year.
For the Southern Hemisphere: If you’re someone who relishes the day’s light, as many do, you might be glad of the sunsets will soon be shifting later!
The exact date of earliest sunrise (and earliest sunset) varies with latitude. At 40o north latitude – the latitude of, say, Philadelphia in Pennsylvania – the earliest sunrise of the year will happen on June 14. For that same latitude, the latest sunset of the year will fall on or near June 27. Meanwhile, the longest day of the year – the day containing the greatest amount of daylight, overall – comes on the solstice on June 21.
So it is for other Northern Hemisphere latitudes. The dates of earliest sunrise and latest sunset don’t coincide exactly with the solstice. Appreciably south of Philadelphia’s latitude, the earliest sunrise has already come and gone (in late May or early June) and the latest sunset occurs at a later date (sometimes as late as July). In Hawaii, for instance, the earliest sunrise precedes the June solstice by about 2 weeks, and the latest sunset comes about 2 weeks after. Farther north, the earliest sunrise and latest sunset happen closer to the June solstice. Check it out at your latitude, using links on our almanac page.
The earliest sunrises come before the summer solstice because the day is more than 24 hours long at this time of the year. In the Southern Hemisphere, the earliest sunsets of the year come before the winter solstice for the same reason.
Enjoying EarthSky so far? Sign up for our free daily newsletter today!
See full size | Sunrise over Currituck, North Carolina. Credit: GregDiesel Landscape Photography
In June, the day (as measured by successive returns of the midday sun) is nearly 1/4 minute longer than 24 hours. Hence, the midday sun (solar noon) comes later by the clock on the June solstice than it does one week before. Therefore, the sunrise and sunset times also come later by the clock, as the tables below help to explain.
For Philadelphia (40o north latitude)
| Date | Sunrise | Midday (Solar Noon) | Sunset | Daylight Hours |
| June 14 | 5:31 a.m. | 1:00 p.m. | 8:31 p.m. | 14h 59m 15s |
| June 21 | 5:32 a.m. | 1:02 p.m. | 8:32 p.m. | 15h 00m 35s |
For Valdivia, Chile (40o south latitude)
| Date | Sunrise | Midday (Solar Noon) | Sunset | Daylight Hours |
| June 14 | 8:12 a.m. | 12:53 p.m. | 5:34 p.m. | 9h 21m 56s |
| June 21 | 8:14 a.m. | 12:54 p.m. | 5:35 p.m. | 9h 20m 39s |
Source: timeanddate.com
The primary reason for the earliest sunrise preceding the summer solstice (and the earliest sunset preceding the winter solstice) is the inclination of the Earth’s rotational axis. The earliest sunrise or sunset would take place before the solstice even if the Earth went around the sun in a circular orbit.
However, the Earth’s elliptical orbit does affect the severity of the phenomenon. At the June solstice, Earth in its orbit is rather close to aphelion – its farthest point from the sun – which lessens the effect. At the December solstice, Earth is rather close to perihelion – its closest point to the sun – which accentuates it.
At middle latitudes, the earliest sunrise/sunset comes about one week before the June summer/winter solstice, and the latest sunset/sunrise about one week after the June solstice.
Yet, at the other end of the year, at middle latitudes, the earliest sunset/sunrise comes about two weeks before the December winter/summer solstice, and the latest sunrise/sunset about two weeks after the December solstice.
Early sunrise in Sweden via Per Ola Wiberg
Early sunrise by Flickr user Raffee
Bottom line: Are you an early riser? If so – if you live in the Northern Hemisphere – you might know your earliest sunrises of the year are happening now. Southern Hemisphere? Your earliest sunsets are around now.
EarthSky astronomy kits are perfect for beginners. Order today from the EarthSky store
Donate: Your support means the world to us
from EarthSky https://ift.tt/1lM9VQO
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