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Evidence of controversial Planet 9 uncovered in sky surveys taken 23 years apart

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Re: Evidence of controversial Planet 9 uncovered in sky surveys taken 23 years apart

#231

Post by [deleted] »

nandomrumber wrote: post #143
zamadatix wrote: post #126

Earlier quoted context omitted.

They're all horrible to conceptualize because people don't commonly deal with how far even something like the Earth to the Sun is, I don't think there is any winning answer here - at least an AU is consistently defined and maybe slightly more likely to be familiar, but it's still just about as crap to be honest. Side note: Apart from AU already being defined as average distance and not current distance, the distance…

700 AU is 4 light days. Or four days travel at the speed of light, to an outside observer. Or instantaneous for anyone travelling at the speed of light.

[deleted]

Re: Evidence of controversial Planet 9 uncovered in sky surveys taken 23 years apart

#232

Post by [deleted] »

iamthemonster wrote: post #211
alex_duf wrote: post #205

700 times further => isn't it farther rather than further? Non native english speaker here, but last I checked further was a metaphorical distance, when farther was a literal distance. You can push a concept further, but you walk farther right? Or did I miss something?

You speak English too well - you have surpassed English speakers. None of us know the difference between further and further.

[deleted]

Re: Evidence of controversial Planet 9 uncovered in sky surveys taken 23 years apart

#233

Post by rkagerer »

cdaringe wrote: post #228
rkagerer wrote: post #166

Earlier quoted context omitted.

1 hour at Warp 4

Ahem, cite your sources? At low warp we’re generally BLASTING by stars!

700AU = 105 billion km (approx)

Warp 4 = 109 billion km/hr

Per https://i.imgur.com/Su1RB.jpeg

https://memory-alpha.fandom.com/wiki/Warp_factor also lists values in a couple charts that check out.

Re: Evidence of controversial Planet 9 uncovered in sky surveys taken 23 years apart

#234

Post by sliken »

haarolean wrote: post #155
api wrote: post #21

Earlier quoted context omitted.

They're not dangerous unless you get too close. A black hole is not a cosmic vacuum cleaner. If the Moon were suddenly transformed into a tiny black hole with the same mass, it would continue to orbit the Earth at the same distance. Ocean tides due to its gravity would continue normally. There would not be much effect except that it would no longer be visible with the naked eye and would no longer reflect the sun's l…

> you might get dangerous X-ray and gamma ray emissions from its accretion disc There’s not enough matter nearby to feed it enough to form an accretion disc > we could send probes to orbit it Hitting a cm-sized black hole orbit at a lunar distance sounds insanely hard, given it’s invisible (even with occasional lensing).

Obviously we've managed to orbit the moon. To find the blackhole that replaced the moon just enter lunar orbit and keep firing your thrusters to slow down.

Re: Evidence of controversial Planet 9 uncovered in sky surveys taken 23 years apart

#235

Post by sliken »

margalabargala wrote: post #65
zveyaeyv3sfye wrote: post #61

Earlier quoted context omitted.

Not sure I want a black hole in my backyard ;-) For all it's worth, there's no need to go black hole to explain the lack of visual observation. Objects that far from a star reflect very little if any light and would appear black to a black background.

Black holes are no more "dangerous" than other objects of equal mass. If a black hole with a mass of, say, Ceres hit the Earth, it would not be particularly worse than if Ceres hit the Earth.

Sort of. Ceres can't turn mass into energy at a ratio that makes fusion and fusion look pretty lame.

On the other hand taking 0.00016 of earths mass, turning it into a blackhole, and shooting it through the earth isn't likely to cause nearly the damage that Ceres (100x size of the dinosaur killing asteroid) ... unless you keep the velocity low enough that it stays inside the earth.

Re: Evidence of controversial Planet 9 uncovered in sky surveys taken 23 years apart

#236

Post by sliken »

colonial wrote: post #165
K0balt wrote: post #127

Earlier quoted context omitted.

Aside from research, it could be used to provoke time dilation, though I’m not sure how much you could get out of a basketball sized black hole.:8

If you're interested in creating time dilation, then a planetary mass black hole unfortunately won't get you any further than, well, a regular planet with the same mass. (Aside: time dilation already occurs on and around Earth. GPS satellites have to account for the fact that time runs ever so slightly slower on the ground.)

Not really, the max acceleration/gravity you can get from earth is around 1G. Even if you tunneled to the center of the earth, you'd get ... zero g.

However with an earth max black hole you could get closer, which would have a higher acceleration, and would time dilate more strongly.

Re: Evidence of controversial Planet 9 uncovered in sky surveys taken 23 years apart

#237

Post by db48x »

sph wrote: post #213
sxcurry wrote: post #160

Earlier quoted context omitted.

I think he’s referring to Mike Brown’s book “How I Killed Pluto and Why It Had It Coming”. It’s a great read.

I didn't know he wrote a book. I was referring to his handle "@plutokiller.com" on Bluesky.

Yea, good book. But he’s wrong. Pluto is still there; nobody has killed it.

Re: Evidence of controversial Planet 9 uncovered in sky surveys taken 23 years apart

#238

Post by mrguyorama »

rkagerer wrote: post #166
NikkiA wrote: post #70

Earlier quoted context omitted.

I dunno, '700 AU' gelled for me instantly, '15 times the distance to pluto' doesn't even make sense given pluto's orbit isn't anywhere near circular.

1 hour at Warp 4

Original formula or Next Generation formula?

Re: Evidence of controversial Planet 9 uncovered in sky surveys taken 23 years apart

#239

Post by stevula »

alex_duf wrote: post #205

700 times further => isn't it farther rather than further? Non native english speaker here, but last I checked further was a metaphorical distance, when farther was a literal distance. You can push a concept further, but you walk farther right? Or did I miss something?

This is, I think, a learned distinction and not universally observed. I only learned this distinction in university.

Re: Evidence of controversial Planet 9 uncovered in sky surveys taken 23 years apart

#240

Post by lolc »

nandomrumber wrote: post #143
zamadatix wrote: post #126

Earlier quoted context omitted.

They're all horrible to conceptualize because people don't commonly deal with how far even something like the Earth to the Sun is, I don't think there is any winning answer here - at least an AU is consistently defined and maybe slightly more likely to be familiar, but it's still just about as crap to be honest. Side note: Apart from AU already being defined as average distance and not current distance, the distance…

700 AU is 4 light days. Or four days travel at the speed of light, to an outside observer. Or instantaneous for anyone travelling at the speed of light.

Thank you. When I want to know astronomical distances, I use the speed of light to get a sense. Moon? One second. Sun? Eight minutes.

Time units are more approachable than distances I will never cross.

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