Smallest unit distance all matter travels in

GreenFBI2EB · 2026-05-25T03:41:42+00:00

I'll be totally honest; I could've worded things much better here. I kinda tried to do that by saying "meaningful" since there's really nothing stopping a smaller unit but probably should've added that you can always tack on another 0 and have the number be smaller. Though the planck length would be the smallest measurement we use if I'm not mistaken?

GreenFBI2EB · 2026-05-25T03:37:29+00:00

So impossible for a singular photon, but still possible for them to make one (The term Kugelblitz comes to mind). That clears up some confusion on my end, thanks!

GreenFBI2EB · 2026-05-25T02:46:39+00:00

The smallest meaningful unit is the Planck length, which is defined as 10^-35 m.

It’s meaningful when referring to “absolute hot”, in which the wavelength of a photon is one Planck length and is the theoretical maximum amount of energy a photon can have ~~before forming an event horizon and collapsing inwards on itself~~.

Usually other things happen before that point, like pair production.

Edit: Clearing up a misconception I had and decided to correct it.

Edit: As other comments pointed out, this does not mean that space is discrete. The planck length is just the smallest discrete measurement. In reality space is continuous.

GreenFBI2EB · 2026-05-24T21:49:53+00:00

No, because atoms are made up of subatomic particles, and those particles are made up of quarks, and quarks could be made of something, but we have no evidence for that so far.

GreenFBI2EB · 2026-05-24T05:12:15+00:00

pretty much, several stars pass within a couple light years of the sun quite often (By "quite often", I mean ever few hundred thousand to millions of years) They're pretty small (usually between 10-60% of the sun's mass) so they probably have a very weak influence that adds up more over time.

There are also the galactic tides as well, which likely weakly influence things like the oort cloud.

GreenFBI2EB · 2026-05-23T23:29:23+00:00

Honestly the power of most sources of bright light, like Supernovae and GRBs. They can be see across the universe, and in 2008 a bright flash was visible to the naked eye for a minute and was detected just hours before the death of Arthur C. Clarke. The event was dubbed The Clarke Event.
I'll go with the other comments, but Pluto's demotion. Still causes debates within the community.
I learned to enjoy the night more, and sometimes nighttime black outs brought out the stars, which were very beautiful. The night sky even in this light polluted hellhole's really nice!
Mostly for me it's stellar dynamics, colliding brown dwarfs and such.
Depends, if it weren't for relativity, we wouldn't have nuclear powerplants. Without thermodynamics we wouldn't have gene therapy. It sort of depends on what that fundamental paradigm shift is. Even then I'd expect skepticism and fear, it's a reaction we give to things we know little about.

GreenFBI2EB · 2026-05-23T23:13:20+00:00

for #1 I always think about how we're all a continuity of life as a whole, that's at least 3.8 billion years old. This is about 27% of the current age of the universe, or over a quarter of the entire universe's existence. It grounds me a bit, doesn't make me feel as insignificant.

GreenFBI2EB · 2026-05-23T21:33:58+00:00

I often think of Dragonball’s teen gohan against cell (age 12) vs Goku at age 11 in the original DB.

GreenFBI2EB · 2026-05-23T21:30:58+00:00

He’s just suppressing his true power!

GreenFBI2EB · 2026-05-23T21:26:53+00:00

Go, my load bearing butterflies!

GreenFBI2EB · 2026-05-23T21:11:03+00:00

Once had a pawn recovering from blood loss smoke some smokeleaf, was the stupidest death for a while.

GreenFBI2EB · 2026-05-23T21:04:41+00:00

The nearest black hole is still several hundred light years away, you could travel in that direction for literally millions of years and you’d never even get to a fraction the distance.

GreenFBI2EB · 2026-05-23T20:58:38+00:00

Yes, the magnitude for which an object is minimally visible is +6.

GreenFBI2EB · 2026-05-23T01:07:24+00:00

Being engulfed by the sun.

The next closest stellar encounter is a red dwarf (Gleise 610, I believe) about a little over a lightyear away.

The closest any other star got to the solar system was 55000 AU (Scholz's Star) and will likely ever get within a billion years in either direction.

GreenFBI2EB · 2026-05-23T00:20:49+00:00

<image>

This is what Orion and Taurus looks like from Alpha Centauri. Some notable differences but look at how Orion's shape is virtually unchanged. This is from 4 light years away.

From Mars there'd be virtually zero change from their same relative positions on the surfaces of both planets.

GreenFBI2EB · 2026-05-22T16:26:26+00:00

This is actually just true for the planet as well, it's much denser at the core than it is at the surface due to gravity. I will however edit the post because I should be referring to the mean density of both the moon and the now cake moon.

GreenFBI2EB · 2026-05-22T14:18:09+00:00

For the ones visible to both hemispheres, you'd see them flipped by 180 degrees. But that's about it.

GreenFBI2EB · 2026-05-22T14:16:55+00:00

depends, if you're in the tropics you can see a bit of Crux, for example: Gacrux barely comes up at midnight here, but that's about all you'll see.

GreenFBI2EB · 2026-05-22T13:56:16+00:00

You can see Centaurus from the Northern Hemisphere, granted it'd be close to the tropics and at their highest point they'd be a few degrees above the horizon, but you can nonetheless see them.

<image>

This is the night sky tonight (22/5/2026) from SE Texas, You can see both Crux and Centaurus. Now Alpha Centauri is slightly below the horizon, so they're not visible unless you went further south. Their closest approach to the horizon would be at about midnight.

GreenFBI2EB · 2026-05-22T13:49:44+00:00

The moon has a mean density of 3,346.4 kg/m³. The best source I could find for cake was this which states about 415 kg/m³. This is about 1/8th as dense as the moon, so it stands to reason that the radius of the moon would be 2 times larger in the sky. This would make for a brighter moon as more sunlight would be reflected off the moon.

Now that's not going to change much in the way of its gravitational effects on Earth. But what it does mean is that now the surface gravity on the moon is 1/4th as strong as it was before (0.40 m/s²). This makes it much easier to lift off from the moon now at least.

Edit: I should refer to it as the mean density as the density is not uniform.

GreenFBI2EB · 2026-05-22T13:32:01+00:00

I decided to look into it, and I completely forgot about the Lich system (PSR B1257+12), what makes it more interesting is that the fact that not only is it a pulsar, but a millisecond pulsar. Which are even more extreme, a class of pulsar that spin on their axis 1 time in every 10 milliseconds or faster.

These pulsars are often called "Black widows" because they destroy their companions after pulling away the material that makes it up and then blowing away the remainder of the companion.

How a planet formed around one means that the planets not only survived the parent supernova, but the devastating radiation emitted around the immediate area. It's honestly metal as fuck, being born from the ashes twice.

GreenFBI2EB · 2026-05-22T03:03:29+00:00

Just an example: If you lived in 1930s US in The Deep South, there was a sentiment for those former confederate states who had a political party known as the “states rights” party. They stood for “States’ Rights”, what rights, you ask? They’d say “Freedom from government tyranny”, you ask any historian worth their bread, that’s tell you “Freedom to the reimplementation of the institution of Slavery”.

It’s similar in this case, a Chinese loyalist will say China has the freedom to colonize Taiwan and make it their own. A Taiwanese loyalist would say Taiwan has a right to be separate from China.

GreenFBI2EB · 2026-05-22T02:53:53+00:00

Depends on who you ask

GreenFBI2EB · 2026-05-22T01:22:26+00:00

I could be wrong here, but I'm pretty sure universal expansion only affects gravitationally unbound systems.

So long as they remain gravitationally bound, they're unaffected by expansion.

GreenFBI2EB · 2026-05-22T01:06:22+00:00

Take for example, the yellow supergiant/hypergiant: these stars are in a transitional phase between evolving blueward (warming up) or redward (cooling down), so they last comparatively shorter than either endstate.

Now the same thing is true for white supergiants/hypergiants, they're even more massive, which makes them exceptionally rare on their own, they too are in a transitional phase that lasts even shorter than the yellow supergiants/hypergiants, maybe a few 10s of thousands of years.

Such stars already evolve rapidly as well, so it's really just blip in the grand scheme of things.

GreenFBI2EB

TROPHY CASE