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It's really, really hard to fire something into the Sun. We can't do it. The same goes for black holes. Things don't just get sucked in. They usually end up in orbit instead.





> It's really, really hard to fire something into the Sun.

It's hard if you aim at the Sun. So don't do that.

You just have to kill your starting orbital velocity relative to the Sun (the efficient way is to fly away out from Earth to higher orbit and then kill your orbital velocity rather than just immediately killing the orbital velocity you get from Earth at Earth's orbital distance -- we can launch craft with enough delta-V to do the former, but not quite the latter, IIRC, with current technology.

> Things don't just get sucked in.

They do unless they have a sufficient component of their velocity at right angles to the Sun to avoid doing that, but that's a solvable problem. You don't hit the Sun (easily) by thrust at the Sun, you hit it by thrusting at right angles to it, in the direction opposite whatever component of velocity you currently have orthogonal to the Sun, and gravity will take care of the rest.


That's not true.

(1) We can launch a rocket that has a payload that hits the sun: it's just costly to do because the rocket starts out orbiting the sun, so we would have to expend delta-v to neutralize the tangential component of the initial velocity.

(2) If you are in a space ship heading towards the sun, it is easy to hit the sun as long as you can steer, and even if you can't steer, if you are heading squarely at it and no planet gets near you to change your velocity, you will hit it.


You are missing the point. Most things that approach a black hole end up orbiting it because they are not aimed directly at its center.

Can you please make your substantive points without swipes? This is in the site guidelines: https://news.ycombinator.com/newsguidelines.html.

Your comment would be just fine without the first sentence.


Pretty sure you (or someone else) decided to pour over my post history looking for violations after I posted this: https://news.ycombinator.com/item?id=43794576

This 3 day old comment was not flagged until just now, what I said is not a swipe at all.


"You are missing the point" counts as a swipe in the sense that the HN guidelines are using the term. Please edit them out in the future. They just add acid to the threads, and you don't need them.

Looking over account histories is standard moderation; of course we do that.


It's a fairly benign sentence selected as the worst thing in my post history due to a witch hunt because I posted a completely unbiased summary of events that was interpreted as right-leaning.

It's not about your other comment, just this one.

Correct link: https://news.ycombinator.com/context?id=43796297

Somehow, I can't edit a 5-minute-old post.


Clearly I am being targeted by dragonwriter for posting something in another thread that they don't like.

Literally, until just now (checking your comment history to see if possibly we had interacted elsewhere that I had forgotten), I hadn't seen or read any of your posts outside of this thread.

Not sure how you got from me responding to two of your posts in this thread that I was "targeting" you for something in some other thread.


> Most things that approach a black hole end up orbiting it because they are not aimed directly at its center.

Most things that approach a black hole aren't trying to hit it.


Can you please not stalk me?



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