Sundown
South Pole Station sits at near-exactly 90° South latitude. Down right here, the solar does bizarre issues. This leads
to accurate-yet-strange sentences, equivalent to “are you able to imagine it – solely 4 extra days till sundown”.
I do know you’re all right here for the scenic pictures, however first indulge me for a bit about how “daylight” works at
polar latitudes.
Any location South of the Antarctic Circle (round 66.5° South
latitude) will expertise 24 hours of consecutive daylight (“midnight solar”),
and 24 hours of consecutive darkness (“polar night time”) at the least
as soon as per yr. Nonetheless – most areas nonetheless get “regular” (every day) sunrises and sunsets for at the least a part of the yr.
McMurdo, for instance, sits at 77.85° South latitude. Nicely under the Antarctic Circle, however nonetheless nowhere close to
as far South as South Pole Station. McMurdo will get every day sunrises and sunsets for a number of months every year,
through the transitional interval between 24×7 daylight and 24×7 night time.
This yr at McMurdo,
the 24×7 “midnight solar” interval ended on February 20. There can be every day sunrises and sunsets till April 25,
at which level McMurdo will enter “polar night time”. The solar will keep under the horizon till August 19.
Then there can be every day sunrises and sunsets till October 24, adopted by one other spherical of midnight solar.
In my Hut Point publish about McMurdo Station, I remarked:
“It’s now early September, and we’re quickly gaining daylight.
We’re getting an additional 15-20 minutes per day, and it’ll be only a
few extra weeks till there’s some gentle 24×7. For now,
the solar is simply barely peeking out from behind the hills.”
That’s McMurdo. Unusual, however not too unusual.
South Pole is the place issues get actually bizarre.
At precisely 90° South latitude, the solar rotates in a near-perfect counterclockwise circle across the sky.
There isn’t a distinction
in any way between “night time” and “day”. On any given day, 2pm seems to be the identical as 2am. The solar is on the identical
top, simply in a special a part of the sky.
The solar reaches its highest level within the sky, about 23.5° above the horizon, across the
December Solstice (December 21).
After the solar reaches its peak, it begins to set. It’s nonetheless rotating in good circles round
the sky; they’re simply getting decrease and decrease every day.
When the solar will get low sufficient within the sky,
normally round mid-February, the temperature begins dropping quickly.
Because of this South Pole Station “closes” for winter round February fifteenth every year. Past today, it’s
operationally troublesome to maintain up flights. Certain sufficient, this yr the temperature began dropping quickly
proper round February fifteenth, as I famous in Last Flight Out.
One of the simplest ways I can clarify that is with a video. This video was initially revealed by
Robert Schwarz, who has spent 15 winters on the South Pole working
for one of many science initiatives right here. It’s reposted right here with Robert’s permission.
Within the video, you’ll see a 5-day timelapse, monitoring the solar, from March 8 via March 13, 2017.
It’s late within the season, and the solar is fairly low within the sky by this level.
Fairly bizarre!
Tangent – all of this makes it particularly foolish that we observe “daylight financial savings time” right here.
We observe New Zealand time, as a result of we needed to decide one thing, and all our logistics run via New Zealand.
A couple of days in the past, I ran round station setting all of the analog clocks 1 hour again,
however it positive didn’t really feel like we had been saving any “daylight”.
Once more, there isn’t a seen daylight distinction between instances on a given day. Now we have a single,
gradual dawn and sundown, unfold out over the course of a whole yr.
I wasn’t notably rigorous taking every day pictures to catalog the solar’s gradual descent, however right here’s a couple of,
exhibiting the date and what the solar appeared like on that day:
The solar right here at South Pole Station lastly “set” on March 23, 2023 at 12:54pm, NZ time. All of us stared out the
window (or ventured exterior) to observe it occur, however it’s actually an anticlimactic milestone. We’re
principally experiencing a single, very bizarre, year-long day/night time cycle. The precise second of “sundown”
(formally outlined because the second the solar utterly dips under the horizon) isn’t actually that particular –
the consequences are unfold out for a number of weeks.
However, right here’s my closest true “sundown” photograph:
And some extra pictures from round sundown:
Because the solar slowly disappears under the horizon, we’re handled to a several-week-long interval of good
colours. The solar continues its counterclockwise rotation, just under the horizon, permitting you to expertise
a sundown from any route you select.
For instance – within the “mornings” (7am), the solar is seen from the
commentary deck at Vacation spot Alpha. Within the evenings, the solar has simply completed passing via the yard.
By about midnight, it illuminates the Ceremonial South Pole out in entrance of the station.
These subsequent few pictures had been taken about 10 days after sundown! It’s nonetheless magical, exhibiting simply how slowly
the solar units.
By April 6, we had our first vibrant moon! And with some lingering daylight from the alternative aspect
of the sky, there was nonetheless loads of gentle, even for digicam telephone pictures:
Optimistically, we must always begin seeing our first auroras throughout the subsequent few weeks!
Throughout Winter right here at South Pole Station, we take our celestial occasions very severely.
On March 25, we noticed Sundown Dinner. This can be a formal affair – a ritual, a celebration, a correct excuse
to revel within the magical absurdity of our state of affairs.
We’re hundreds of miles from civilization, it’s -80°F exterior, and we’re marching towards
six months of darkness, with solely ourselves to depend on. Time to have fun!
Our galley crew goes all-out to arrange. The decor, the ambiance, the meals… the whole night is a
curated masterpiece. It’s probably the most enjoyable all-station evenings I’ve had thus far.
We’re now passing via all the assorted levels of Twilight,
on our method in the direction of night time.
From March 22 via April 5, we had been in Civil Twilight.
From April 5 via April 22, we’ll be in Nautical Twilight.
From April 22 via Might 12, we’ll be in Astronomical Twilight.
From Might 12 via August 2, it’ll be night time, and totally darkish, with solely occasional gentle from the moon.
Then we’ll repeat the cycles in reverse, culminating in dawn across the
September Equinox.
This afternoon, as I used to be placing the ending touches on this publish, I stepped exterior and noticed a star
vibrant sufficient to catch on digicam. We’ll be seeing much more of those over the following few months!
Additionally – it’s COLD out.
Till subsequent time!