The first 'major lunar standstill' in more than 18 years is about to occur | Hacker News Reader

The first 'major lunar standstill' in more than 18 years is about to occur

livescience.com

65 pointsbelter19 comments

Why is it called a standstill? A lot of words in that article and not much information.

https://en.wikipedia.org/wiki/Lunar_standstill#Origin_of_nam...

tl;dr for the lazy (but I'm not very smart so don't trust me): the moon and earth orbit each other such that the moon cycles between rising high in the sky and low in the sky every ~2 weeks.

Lunar Standstill is when our orbits align each other such that if you were to casually stargaze at the moon for a few nights in a row, it would seem to keep going to the same spot.

Pretty cool imo, but I think you'd have to really be into the topic to appreciate it. It's pretty obscure knowledge!

Seems like you have to be a real moonhead to appreciate this event.

So basically the moon's position follows a combination of several sine(ish) waves, and this is (close to) a global maxima of that combination?

You and the article both say "high" which I would usually assume to mean "high altitude", but in this case it means "northerly azimuth"?

You're close, but it's not a few nights in a row, it's a few months in a row - the standstill is that it returns to the same angle above the horizon on each orbital pass (month), and thus to the same spot in the sky. (Night to night, the moon isn't in the same spot, because it's revolving along its ellipse to a different true anomaly position.)

The event lasts months, but as I read, but if you compared the position over the course of more than a week, you’ll notice a difference in position. Sorry if I wasn’t clear!

Possibly a better explanation than the sibling comment: The plane of the moon's orbit wobbles relative to the Earth's equator, with a period of 18.6 years. The "standstill" says that the moon apparently follows the same track from each orbital pass (month) to the next - it refers to the change in the moon's declination (angle above the horizon) at the same point in its orbit on successive months. At the time of a standstill, this change is at its minimum value, because the difference between the moon's orbital plane and earth's equator is momentarily at one extreme of the wobble (the peak or trough of a sinusoid.)

"First in >18 years" is a clickbait headline - the interval is always that, there's nothing special about this one. It's as regular as saying "first full moon in 29.5 days".

> It's as regular as saying "first full moon in 29.5 days".

"the first sunrise in 24 hours!"

Darkness is coming!

https://xkcd.com/1391/

Well, that's not universal:

https://www.timeanddate.com/sun/norway/tromso

Does anyone have a good calendar that shows interesting celestial events for say the next 10 years?

https://eclipse.gsfc.nasa.gov/SKYCAL/SKYCAL.html

This seems like the best resource that includes planets and meteor showers

Some events aren’t really calculated for, e.g. some comets appear spur of the moment

Worse, dying stars seem to have a mind of their own when it comes to going Supernova.

At the very least there's enough neutrino detectors on earth that we should have some warning a while before we can see it happen. (neutrinos are less affected by gravity while travelling away from the exploding star so they'll reach us before the light does)

This is a thing: https://en.wikipedia.org/wiki/SuperNova_Early_Warning_System

> The SuperNova Early Warning System (SNEWS) is a network of neutrino detectors designed to give early warning to astronomers in the event of a supernova in the Milky Way, our home galaxy, or in a nearby galaxy such as the Large Magellanic Cloud or the Canis Major Dwarf Galaxy.

Not a supernova, but this nova is expected any day now, in the next few months: https://www.space.com/new-star-2024-T-Coronae-Borealis

The New York Times has a pretty good space-related events calendar feed.

It's made in Google Calendar, but should work everywhere. (I use it on macOS Calendar.)

https://calendar.google.com/calendar/ical/nytimes.com_89ai4i...

With this and the subs magnetic field shift on the front page, for the briefest of moments I wondered if they were somehow connected.

This would make for a good js visualization challenge

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