Most people don't know off-hand that Pluto is ~40-50AU from the sun, so 700AU is hard to conceptualize.
Side note: Apart from AU already being defined as average distance and not current distance, the distance referenced is how far out the proposed object is now, not its general orbital parameters. At that orbital distance 23 years of motion isn't going to be much change in distance even if it's in a hyperbolic orbit.
https://imagine.gsfc.nasa.gov/features/cosmic/nearest_star_i...
~30-50AU if you are referring to the range of orbital distance.
Or 698 trillion bananas.
But if you got “15x further than Pluto” you have context without needing to know any other trivia-style numbers.
Also it’s not like distance to Pluto is a meaningful number either since it’s extremely variable . AU at least is fixed
15x means no one alive today will see a mission that reaches the planet, and that's more accessible for most readers per above.
(9.5 * 15 / 3 = 47.5) + 30 years = 77.7 so some teenagers could live to see a probe reach it even without hypothetical life extension technology.
Then to show Planet 9 distance they have to get in a car and drive a few miles.
That worked for me.
It communicates the scales really well, while only taking up a little over a foot of bookshelf space when not being "navigated". I have two heavy metallic retro looking rocket bookends for it.
I wonder how could this object be counted as a "planet" belonging to the Solar system, even if it were the size of Jupiter. But it's an object "estimated to be 2 to 4 times the radius, and about ten times the mass of the Earth". This must be another class of celestial bodies, some jumbo-sized Oort cloud object.
Also depending how elliptical the orbit, is the perigee might be much closer than 700AU, while still being further than Pluto's orbit. For all we know 700 AU is the apogee and say the perigee is 70 AU (1.4x Pluto's apogee ).
The body must also be large enough to clear other bodies in the same orbit, except at the Trojan positions (L4 and L5), to be considered as a planet. Otherwise it would just be a Trans-Neptunian Object (TNO) or a Kuiper Belt Object (KBO) at these distances.
It obviously does in this case. But this pedantic detail is rather important. It was used to demote Pluto a few years back.
I guess I’d always put all the gas giants in the same “very, unimaginably big” bucket. I knew Jupiter was the biggest, then Saturn, but I didn’t realize just HOW big they were compared to the rest. At the risk of stating the very, very obvious, Jupiter is huge!!!
Masses of gas giants are: Jupiter, 317.8 earth mass; Saturn, 95.2 earth mass; Neptune, 17.1 earth mass; Uranus, 14.5 earth mass
[0] https://en.m.wikipedia.org/wiki/Earth_mass#Unit_of_mass_in_a...
It seems like the idea was to send a bunch of instruments way out and then take pictures in the brief time they were at a useful distance, but if there's a planet out there we can orbit and so stop the instruments at that distance it seems like we could make a permanent super telescope.
* 700 times further from the Sun than the Earth
* 15 times further from the Sun than Pluto
* 0.01 lightyear, or 1/400th the distance to the nearest star
Or, it's the difference between going for a 15 minutes walk and walking from Boston to Orlando (or San Diego to Seattle, for the West Coasters).
Hutton Orbital is located approximately 6,784,404 light seconds, or 0.22 light years, so this will be 50 hours of non boosted SC.
Pluto is a fairly unremarkable dwarf planet. I don’t think it really helps to compare things to it.
I don't need to sue you. It's just entirely incorrect by any sane definitions of a planet. It's not the further if you include similar bodies or not a planet. As I have no interest in saving American misplaced pride (because let's not kid ourself it's about anything else), I don't see the point of spreading misinformation.
> Because more people know about Pluto than Eris or Sedna
Only if you were born before it was retrograded which will be less and less likely as time goes on.
> My cosmological knowledge is above average, but I don't know off the top of my head if 700 AU is super-duper far away or still in the range of the gas giants.
I'm not convinced that giving it in multiple of the distance between Pluto and the sun is in any way more useful than distance between the Earth and the sun or that it helps conceptualise the distance relative to the gas giants.
Anyway, Pluto orbit is highly excentric so you have 20AU of wiggle room here when considering distance.
700 further from the Sun than Earth is tangible as "really really far" though.
Another perspective on the size of the solar system, like the Pale Blue Dot.
It could also allow gravity and Oberth effect acceleration of small probes to meaningful fractions of the speed of light for interstellar flyby missions. Imagine the Oberth effect boost from thrusting in such a deep gravity well.
We don't have enough data to see whether there are unexpected instabilities in detected planetary systems. But it would be an interesting project to look for those.
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 light back to Earth. If you found it in a telescope, you might see gravitational lensing as it passed in front of the star field. Objects like probes or old spacecraft stages orbiting the Moon would continue to do so.
The only danger would be that if things fell into it I suppose you might get dangerous X-ray and gamma ray emissions from its accretion disc that would be a problem at such a close range. That would not be an issue with a primordial black hole much further away.
If there were such an object we could send probes to orbit it and study it, and some experiments may involve firing objects or shooting lasers or beams of particles into it to attempt to learn about the quantum effects at the event horizon. This could be massive for physics, allowing us to access and observe conditions and energies not replicable here on Earth with any current technology.
BTW we don't have any hard evidence that primordial black holes exist, but many theories predict them. So far such predictions around black holes have a pretty good track record. If you made me bet, I would bet on them existing. They are a candidate for some or perhaps even all of dark matter, though even if that's not the case they might still exist. It's possible that the dark matter haloes we can spot with gravitational lensing are clouds of these things. ("Clouds" of course is a misnomer-- the distance between them would be many light years.)
If planet nine is a PBH it means that at some point one was captured by our solar system into a Kuiper Belt orbit. Even if planet nine isn't one, there still may be small asteroid mass PBHs in our solar system, so we still might find one. They would require extremely sensitive X-ray or gamma ray telescopes or highly accurate gravitational models of the solar system to detect.
Let’s fire up a replica of TARS, load up ChatGPT inside (TARS-GPT, patent pending), and yeet it straight toward the Schwarzschild golf ball. It’ll narrate live.
Imagine the livestream:
“Approaching event horizon. Spaghettification at 3%. Mood: stretchy.”
“Entering gravitational lensing zone… wow, even my tokens are redshifting.”
Bonus: With the right timing and Oberth maneuver, TARS-GPT might sling itself into Alpha Centauri before we finish arguing whether Pluto’s a planet again.
Worst case: we lose a robot. Best case: we unlock quantum gravity and get a podcast from inside a black hole.
I'd call that a win.
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.
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.
Domesticating fusion would be much easier. That is within sight.
https://arxiv.org/pdf/1909.11090
As I recall, it did not get printed this way because the ink would be too expensive, or mess with the paper.
That's the idea behind this paper (and similar ones like it): since they're looking for the planet's intrinsic emissions, from its internal heat, it's only a single inverse-square law.
With d being ~20 times Neptune's distance and ~140 times Jupiter's, these really are large factors!
Is my calculation correct?
https://bsky.app/profile/plutokiller.com/post/3lnqm2ymbd22r
If those two spots are the same object, that object is on a high-inclination orbit; but the pattern the Planet 9 hypothesis explains is only compatible with a low-inclination object.
You mean Eris? Pluto is ~10 times the mass of Ceres.
Seriously though, is he one of the people responsible for Pluto's demotion to dwarf planet?
Back in the early 1800s children used to memorize the names of the 12 planets: Mercury, Venus, Earth, Ceres, Pallas, Juno, Vesta, Mars, Jupiter, Saturn, Uranus, and Neptune. But then in 1845 astronomers discovered Astraea, and now there were 13. In 1847 three more were discovered: Hebe, Iris, and Flora. Then Metis, Hygiea, Parthenope, and Victoria by 1850. The 100th asteroid was discovered in 1868, and the pace only got quicker from there. Somewhere along that line people started using the words “asteroid” and “asteroid belt” and schoolchildren were mercifully spared the pointless task of memorizing hundreds, and later many thousands, of names of asteroids.
The same thing happened to Pluto. Just as Ceres was the first discovered asteroid, Pluto was the first discovered TNO. There are now hundreds of named TNO and thousands more that are just numbered. Nobody should force schoolchildren to memorize them all. Just tell them that there are an unknown number of objects in the Kuiper belt and the Oort cloud and they’ll know as much as they need to know. Give them bonus points if they know the names Ceres and Pluto, and more if they know why these two were discovered first of all the objects in their class: they’re the biggest. Otherwise there’s nothing special about them.
Or just tell them that there's an unknown number of planets in the solar system, but the big 8 are the only ones they're expected to memorize. That was actually the original plan by the IAU, and how many (I believe most) planetary scientists define planet today.
The decision being based mainly on not wanting to add newly discovered planets to the list of planets in the solar system always rubbed me the wrong way. As is the tendency for people to mistakenly believe that this is settled science, when it's actually an unsettled nomenclature debate.
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?
Sure, we wouldn't be able to get there for many decades, but "within a century" would be feasible.
There are so many unknowns surrounding the nature of black holes. Having one in our backyard would give us a chance to test our guesses.
(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.)
https://science.nasa.gov/universe/exoplanets/exoplanet-disco...
By comparison the entire Kuiper belt – including Pluto – is estimated to have a total mass of about 10% of Earth's mass.
Of course, all of this comes with the caveat that nothing like this may exist yet. Sealed mass ecosystems exist in glass jars, but something on the scale of a ship is going to be an entirely different ballgame.
Here is a nice graphic that excludes Ceres https://en.m.wikipedia.org/wiki/Dwarf_planet#Population_of_d...
The motivation for this dwarf planet nonsense was to try to keep the official planet list small so children could memorize them with ease, but that is absurd. We do not remove countries from the map to make it easier for children to learn geography and there are over 100 of them.
The list was stable at 12 for about 40 years, but started growing again in the middle of the century. By 1868 there were 100 named asteroids. Not a single one has people living on it, so making children memorize their names was seen as a waste of time. Teach them about the asteroid belt and then move on to more important things. Likewise with the TNO: teach them about the Kuiper belt and the Oort cloud and then move on to more important things. No need to make them memorize Pluto, Haumea, Makemake, Gonggong, Quaoar, Sedna, and Orcus, nor any of the hundreds of other named TNO.
Nonsense. "Pluto is grandfathered in as a planet, nothing else is a planet". See?
Was earth not a planet shortly before and after collision with Theia?
The naming pedantry seems ridiculous given that we have such a small sample size.
To steal a quote: All definitions are wrong. Some are useful.
Hell, what's it called now? Jupiter's orbit is shared with millions of Trojans. Many of them are more than a hundred kilometers in diameter; for reference, Deimos, one of Mars' moons, has a mean radius of about 6 km.
To discover Planet 9, simply open your ephemerides and look for "Neptune".
