Here is the sky at midnight between November 2 and 3.
See the end note about enlarging illustrations.
I’m showing a tall slice of the sky, up to altitude 70°, because I want to point out something up there.
Local clock time now agrees with natural time in calling this moment 0, rather than 11 PM, because clocks shifted back on the night between Oct. 31 and Nov. 1.
However, the “midnight” picture’s even more exact time by the Sun is a bit different, because of what’s called “the equation of time.” You can find a full explanation of that by clicking on the “Astronomical Calendar Any-Year” tab at the top, and scrolling down to “Equation of time.” Here’s a graphic from it:
The “equation,” or amount to subtract from exact solar time to equalize it to the mean or average time that we use in our clocks, reaches its maximum for the year on November 2.
This means that the Sun at real midday is 16 minutes past its average midday position. And you can see, at the top of our sky scene, that the anti-Sun, or point opposite to the Sun, is 16 minutes past the meridian, a vertical line from the south point on the horizon.
The thin Milky Way of winter has yet to swing over the meridian. Still, even in the dim constellations of the “watery” region of the sky such as Cetus and Eridanus you should at midnight see stars.
Home Planet Department
Here’s a starry sky such as a long-exposure camera sees, in a bizarre context.
These stars are so many that it’s difficult to recognize anything. The light-smear parallel to the wall seems like an artefact, but is it the Milky Way? If so, is the darker smear the dark Cygnus rift, and can you identify what seem to be two clusters? I’d guess that the camera was looking roughly south, from the US side of the wall.
Trump’s “beautiful” wall against Mexico, with the image of a jaguar projected on its steel struts. (Photo from The Guardian, Oct. 27.)
The 371 miles of wall so far built (the border is 1,954 miles long) have torn up fragile environments, depleted groundwater for making concrete foundations, and separated populations of animals from each other and their food sources. Jaguars have almost vanished from the US over the past century, because of habitat loss and hunting, and the wall is expected to finish them off.
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ILLUSTRATIONS in these posts are made with precision but have to be inserted in another format. You may be able to enlarge them on your monitor. One way: right-click, and choose “View image”, then enlarge. Or choose “Copy image”, then put it on your desktop, then open it. On an iPad or phone, use the finger gesture that enlarges (spreading with two fingers, or tapping and dragging with three fingers). Other methods have been suggested, such as dragging the image to the desktop and opening it in other ways.
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This weblog maintains its right to be about astronomy or anything under the sun.
Hi, Guy! The evening darkness seemed to hit harder and sunset earlier than usual. I immediately noticed the Sun being slow would make the sunrise time from morning time change seem not as late and the sunset time seem earlier. But, near White Plains, New York, where I live, next year’s first sunset after the time change on November 7th is even earlier (on the clock) than this year’s on November 1st as the sunset is earlier later in November (of course). So, I guess it has nothing to do with the equation of time?
The night sky scene is an unusual orientation for sure ~ I think the diamond-shaped grouping at left is Delphinus, the Coathanger or Brocchi’s cluster is at lower left, Deneb is to the upper left of the Jaguar, Cassiopeia is above the Jaguar’s neck, and finally the double cluster in Perseus is at the upper right. Digital cameras for some reason show a different view of the stars than film pictures. Bright stars are not nearly as prominent in digital images as they are on film, so it can be difficult to figure out what scene you’re looking at sometimes.
I’m impressed by your ability to read this image!
Especially when a digital camera is set to a long exposure and high ISO, the CMOS detectors in digital cameras are much more sensitive to light than an old-fashioned film camera. So lots more pixels get lit up in a digital image. But on a long exposure most of the pixels are saturated, so most stars appear equally bright. That makes it a lot harder to find the few bright stars that define the constellations.
Also, this is a really wide angle image, covering, what, at least 90 degrees of sky? When we’re looking at the real sky we can comprehend maybe 20 or 30 degrees in one glance. Coincidentally, this image on my computer monitor is about 20 degrees wide. So I need to remember that I would never see that much sky at one glance.
Maybe 20 degrees is the diameter of the field we can concentrate our attention on. But I can see my left and right hands simultaneously in peripheral vision each 100 degrees from the center. So the “seen” field is 200 degrees wide.
Unless your computer monitor wraps around your head from one ear to the other, a 200 degree wide image is going to look very different on a screen than the same swath of sky looks in reality. I always have a hard time getting oriented in such very wide field images.
Astronomical insights 👍👍
Implicitly supporting BLM bullies and looting 👎👎
I believe the border wall is managed by the Border Patrol. The Bureau of Land Management is generally more benign.
Oi vey! The BBC chimed in more recently than my last : https://www.yahoo.com/news/trump-wall-much-actually-built-000218486.html
On the matter of the wall, there is more to know: https://www.bloomberg.com/news/articles/2020-09-01/the-border-wall-that-u-s-not-mexico-is-paying-for-quicktake#:~:text=When%20Trump%20took%20office%20in%20January%202017%2C%20barriers,border%2C%20mostly%20in%20California%2C%20Arizona%20and%20New%20Mexico.
I say, though, old chap, is the Chunnel open for all comers without restrictions? Asking for a friend.
It’ll tear up the night sky too if Trump decides to floodlight his wall.
A few years ago I spent a night observing the winter sky from an observatory along the wall on the U.S. side in San Diego County, a few miles from the SDAS. It was dark. Although the Border Patrol made several visits to the property during the night on their normal rounds, there was no floodlights on the U.S. side. The only significant light pollution was an orange bubble down Mexican way my host explained was from a Mexican prison. So no, nobody was floodlighting the wall.
My actual experience doing celestial observing from an observatory located next to the border fence from the U.S. side in rural San Diego County was that all of the light pollution was coming straight up and out of Mexico.
It doesn’t surprise me as in my experience Central America has a lot of light pollution.i can’t remember Mexico and I think that the Moon was full when I had a go at stargazing from a hotel balcony in Acapulco but I did manage to spy a few stars in Tucana.I remember that Guatamala was bad for it.Belize and El Salvador weren’t too bad and I had fine views of the Southern Cross from a village called El Zonte,El Salvador;the Southern Cross rising out of the crashing Pacific but even then the hotels had started fitting floodlights to the base of coconut palms to show off the trees at night,as if they didn’t have plentiful daylight hours to look at them!