Earliest sundown isn’t on the shortest day
For the southernmost U.S. and comparable latitudes – round 30 degrees north latitude – the earliest sunsets of the 12 months are occurring round now, as a result of they arrive in late November and early December. For latitudes farther north – round 40 degrees north latitude – the 12 months’s earliest sunsets will occur within the coming week, the week of December 5, 2022. For example, that may be the latitude of New York Metropolis; Philadelphia, Pennsylvania; Kansas Metropolis, Missouri; Denver, Colorado; Reno, Nevada; Beijing, China; Madrid, Spain; and Naples, Italy.
In the meantime, what concerning the Southern Hemisphere? At this identical time, for 40 degrees south latitude, the 12 months’s earliest sunrises occur this week, as you progress towards your longest day on the December solstice.
Then, nearer to the Arctic and Antarctic Circles, the earliest sundown and earliest dawn occur nearer the solstice.
Need to know the date of your earliest sundown (or dawn)? Sunrise-sunset.org gives the dawn/sundown instances to the second, for areas across the globe.
In reality, the precise date of the Northern Hemisphere’s earliest sundown and the Southern Hemisphere’s earliest dawn varies by latitude.
However, at temperate latitudes, each of those annual hallmarks in our sky come a couple of to a number of weeks earlier than the December solstice, not on the solstice as you would possibly anticipate.
Why?
The subsequent solstice in 2022 comes at 21:48 UTC on December 21 and marks an unofficial starting for winter within the Northern Hemisphere. So for the Northern Hemisphere, this upcoming solstice brings the shortest day and longest night time of the 12 months. Then why isn’t the earliest sundown on the 12 months’s shortest day?
Principally, it’s due to the discrepancy between the clock and the solar. The very fact is, a clock ticks off precisely 24 hours from one midday to the following. However an precise day – as measured by the spin of the Earth, from what is named one “photo voltaic midday” to the following – hardly ever equals 24 hours precisely.
Additionally, photo voltaic midday is just referred to as noon, as a result of it refers to that instantaneous when the solar reaches its highest level for the day. Thus, within the month of December, the time interval from one photo voltaic midday to the following is definitely half a minute longer than 24 hours. For instance, in Philadelphia, Pennsylvania, on December 7, the solar reaches its noontime place at 11:52 a.m. native commonplace time. Then, two weeks later – on the winter solstice – the solar will attain its noontime place round 11:58 a.m. In order that’s 6 minutes later than on December 7.
Go to Sunrise Sunset Calendars to know the clock time for dawn, photo voltaic midday and sundown plus day size in your a part of the world, remembering to test the photo voltaic midday and day size packing containers.
One other key level, the later clock time for photo voltaic midday means a later clock time for dawn and sundown. This may be seen within the desk beneath.
For Philadelphia, Pennsylvania
| Date | Dawn | Photo voltaic Midday (Noon) | Sundown | Daylight Hours |
| December 7 | 7:08 a.m. | 11:52 a.m. | 4:35 p.m. | 9 hours 27 minutes |
| December 21 | 7:19 a.m. | 11:58 a.m. | 4:38 p.m. | 9 hours 20 minutes |
Newest dawn and earliest sundown aren’t on the solstice
As you might need guessed, the newest sunrises aren’t on the day of the solstice both. So for center latitudes within the Northern Hemisphere, the newest sunrises are available early January.
Nevertheless, there’s variation within the actual dates, however the sequence is at all times the identical for each hemispheres. First, earliest sundown earlier than the winter solstice, the winter solstice itself, newest dawn after the winter solstice. Then, half a 12 months later: earliest dawn earlier than the summer season solstice, the summer season solstice itself, newest sundown.
So by all means, try the earliest and newest sunsets and sunrises in your space. As a result of they’re at all times beautiful and occur round each solstice.
Sunsets from the EarthSky Neighborhood
Backside line: The solstice comes on December 21, 2022, at 21:48 UTC. However the earliest sunsets at mid-northern latitudes – say, 40 levels north latitude – occur on and round December 6 or 7. By comparability, latitudes nearer to the equator had their earliest sunsets in late November, or earlier in December. After which latitudes nearer to the Arctic Circle could have their earliest sunsets nearer to the December solstice.
Solstice tale of two cities: New York, New York, and St. Augustine, Florida
Planet-observing is easy: Top tips here
EarthSky’s monthly night sky guide: Visible planets and more
