r/askastronomy

At singularity does any mass exist?

Is it inevitable that a black hole keeps going up in size over ‘time’ as it keeps gobbling up its surroundings? (I couldn’t help use ‘time’ in the sense we understand it, and I don’t know what time means to a black hole).

If it is all due to mass, isn’t there a limit for density? If not, what chemical element would the mass be?

If we were to get inside the event horizon would everything around us look bright or dark?

I know that most if not all of the singularities of black holes are spinning becouse the star that turn into black hole have initial rotation and that rotation is maintained.

Is it in theory possible for a black hole to not spin?
If yes, would that black hole still have event horizon in the form of disc? Or would it be a sphere?

How would that affect the image of black hole, would it just be completly dark w/o acretion disc?

Wierd phrasing, as the moon its tidally locked to would be orbiting the planet WAY faster than the other one (at the speed the planet spins around it’s axis = 1 orbit[month] pre day).

From what I’ve gathered, a planet can be tidally locked to its moon (not entirely sure about Earth-like planets though). But could the system have a third body, which orbits the planet at a slower pace, and thus appears from the surface like our moon does: rising and falling during the day? I would assume the tidal force of the “orbiting” moon would interfere with the tidally locked one, but also that the tidal force of the planet would be greater, so idk. What would be the requirements for this to work? (sizes/distances of the moons etc.) Google isn’t helping.

This is for a worldbuilding project, so assume the planet is habitable. I was experimenting with a planet having a “secret moon” that always stays in place and thus is only visible from one hemisphere.

Any insights you might have are welcome. Thanks!

Time: between 11:30 pm-3 am (when I finally went to sleep - and they could have started sooner but that’s when I was looking). Night of May 16-morning of May 17
Location: just south of Santa Fe, NM

I almost continuously saw small moving lights (like satellites) emerging from one fairly small region in the sky — northern direction — and moving slowly and steadily for 10-30 seconds ish in an eastern direction until they disappeared. It was a fairly steady stream for hours. There had to have been hundreds over the course of that time. These were sometimes fairly close to the horizon but sometimes further up.

Sometimes one would emerge, sometimes a couple at different nearby points, sometimes several. They all traveled at generally the same pace and the same direction until they disappeared.

Sometimes they were more faint and sometimes they glowed brighter. Once there were a cluster of 5 that emerged at the same time. After a few seconds they appeared to line up vertically, three in a row, then one off to the side left, and the fifth back in the vertical line. They glowed brighter once aligned and then moved out of formation and then disappeared. A few times I saw two emerge close together and they appeared to get closer and when they were right next to each other one or both glowed super bright.

As the night went on, the emergence and disappearance areas remained the same except they shifted eastward due do earth’s rotation.

Could these have been satellites? The sheer continuous volume over the course of hours has me questioning…

What is that one thing which you found out about the laws of physics or how universe behaves that has left you startled?

Say I could magically keep adding mass to an asteroid, I imagine I could eventually get a planet sized object, but what about beyond that? Would I eventually get something like a gas giant or eventually a star, then different kinds of stars? What happens if I keep going?

Why is it that it must be called the Moon rather than just Moon? For any other satellite, you would say "Io orbits Jupiter" and not "the Io orbits Jupiter" but for some reason you cannot say "Moon orbits Earth". It has to be "the Moon orbits Earth". The same thing also applies to the Sun where it has to be the Sun rather than just Sun. Why is this?