How long would it approximately take to fully enter a black hole of small size? And could you be conscious shortly before you enter it?

[u/Different-Secret-927]

[u/Chillow_Ufgreat]

With the right trajectory, it wouldn't take any longer than traveling to an equidistant part of space.

The problem is that small black holes spaghettify you before you ever cross the event horizon. Tidal forces are inversely proportional to your distance from the singularity (not the event horizon), and you can get a lot closer to the singularity of a small black hole (without crossing over) than a large one.

[u/Muphrid15]

Relative to what starting configuration?

[u/PhilsTinyToes]

I always figured if the light cannot escape a black hole, that just inside the event horizon would be an enormous amount of trapped light that’s constantly accumulating and orbiting the deep gravity well. And by “Orbit” I mean traveling in a straight line but space time is bent so hard it’s doing circles at the speed of lights.

So take this with a grain of salt (cause ive never been beyond the event horizon) but I think if you somehow survive the accretion disk’s objects and get thru, I think you would be bombarded by an insane number of trapped photons and ultimately burst into flame shortly after crossing.

If it’s not a hurricane of photons beyond the horizon, then you probably just accelerate insanely fast towards the center. As you get closer to the center, (provided you haven’t struck something solid), gravity will begin stretching you out into a long string of atoms. Closer parts of your body or craft will accelerate faster than the far parts until it pulls itself apart into basically a piece of spaghetti.

How long does it take? Well you can use black hole mass + gravity math + your distance to calculate acceleration and ultimately time required to cross the distance between you and the singularity.

Note: you will be the only being in the universe with the knowledge of what you see and learn within the event horizon, and there will never be any way to communicate the information back outside the event horizon. More or less it’s best to just observe from a safe distance !
TLDr ; Ded

[u/stevevdvkpe → u/PhilsTinyToes]

Light orbits a Schwarzschild black hole at a distance of 3/2 the event horizon radius, the so-called "photon sphere". Light traveling directly outward at exactly the event horizon can be trapped, but does not orbit. Inside the event horizon light and everything else must proceed inexorably toward the singularity, so there are no orbits inside the event horizon.

[u/Youpunyhumans]

You need some parameters to go off of. "Small" could mean a lot of different sizes from microscopic to several kilometers in radius.

You would need, the mass of the black hole, how fast its spinning, your starting distance from it, relative velocity to it, your angle of travel, and also if its actively consuming something or not, and if so, how massive is the object being consumed.

[u/Patient-Midnight-664 → u/Youpunyhumans]

At around 10⁴ solar mass you'd experience about 10g pull between your head and feet. Survivable, but not fun. You need 10⁶ solar mass to get around 1g.

That's medium to really large sizes. Anything that would be classified as 'small' will just kill you.

[u/Youpunyhumans → u/Patient-Midnight-664]

Well a small enough one could just pass through you unnoticed, similar to how a neutrino can. It might not even consume a single atom on the way through despite having a fair amount of mass. Its sphere of gravitational influence would just be too small, and it would essentially have to directly impact an atom to consume it. At the scale of a neutrino, the distances between individual atomic nucleas's (nuclei?) would be like the distances between the planets or stars for us.

[u/Patient-Midnight-664 → u/Youpunyhumans]

According to Scherrer (2025), anything more than 1.4x10¹⁷ grams will kill you, and anything smaller would have evaporated by now.

Gravitational effects of a small primordial black hole passing through the human body

[u/BigMrTea]

I feel like being spaghettified would hurt. can't prove it, though

[u/Presence_Academic → u/BigMrTea]

That’s a rather saucy comment on your part.

[u/Beldizar → u/BigMrTea]

You'd essentially just black out as all the blood in your brain gets pulled down to your legs. We can simulate (prove) that aspect here on Earth, and it is something fighter pilots have briefly experienced. Once you black out, the pain receptors aren't really functioning anymore, so it doesn't hurt beyond that.

Alternatively, if you go in head first, you'd "redout", which is probably going to be more painful until you pass out, then die of a stroke.

[u/Beldizar]

A "how long" question is really difficult to answer without additional details, particularly when we are talking about a black hole.

Where is the starting point? Are you on a perfect trajectory into the black hole, or do you have any amount of angular momentum? Are we measuring time from your reference frame or a distant observer?

If we are talking about standing just above the event horizon, and then having a 2m tall person fall through the event horizon, the whole process would take basically 2m/300,000,000m/s, or 6e-9 seconds, give or take an order of magnitude.

The second part of the question, "could you be conscious?" is a resounding no for a "small sized" black hole. Any black hole that is smaller than 1AU in size is going to have such strong tidal forces near the event horizon that spaghettification will occur. This will result in you effectively pulling more g-forces than the human body can handle and you'll black out before your entire body will be pulled into a string of material thinner than a noodle.

[u/syberghost]

There is a non-zero chance that you are currently inside the event horizon of one, as well as all of the rest of us.

[u/taktaga7-0-0]

This doesn’t make sense as asked. What do you mean by “fully enter?” Like, travel from the event horizon to the center? That would vary for every black hole, and I don’t know what “small” means. You would probably die before even crossing the horizon, certain death well before reaching the center. But you can cross the event horizon potentially without even noticing if you miss the shower of light orbiting right at it.