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Space Is Full of Planets, and Most of Them Don't Even Have Stars
- senectus1 8y agoI wonder what happens to the planets in the solar system when a rogue planets gets sucked into the star (sun) ? I mean, yeah it'd be bad if a rogue planet smashed into us, or even came close enough to mess with our gravitational pool (or the moons). but I imagine if an earth sized or bigger slammed into the sun, that we'd feel the effects of this. massive solar flare roasting our planet alive? a shower of ejecta from the collision that we pass through? it changes the mass of the sun in a significant way that changes the pull it has on the planets around it?
- redler 8y agoWatch the film “Melancholia” for a dark take on the effect of a rogue planet.
- gnulinux 8y agoI was about to suggest this movie, but since someone else suggested it, I might as well note that Melancholia has more to do with other things than "a planet crashing into earth". It's more of an existential catastrophe than a terrestrial catastrophe.
- tehlike 8y agoNot much would happen: https://gizmodo.com/what-a-giant-solar-flare-would-look-like-next-to-earth-1784659680 https://gizmodo.com/what-a-giant-solar-flare-would-look-like...
- Thorondor 8y agoThat's very, very unlikely. A rogue planet passing near a star wouldn't crash into the star, it would follow a hyperbolic trajectory out of the system.
- PhasmaFelis 8y agoI haven't done the math, but I'd be mildly surprised if there were any dangerous effects. The Sun is just so big relative to even the largest planets, and much much denser as well; I suspect that most of the ejecta thrown up by a collision would be pulled back down the gravity well before reaching Earth orbit, and the mass of a planet is so small compared to the Sun that I doubt it would alter its gravity well appreciably.
- duxup 8y agoWould a earth sized planet really make much a difference if it hit the sun? Considering the size difference I'm not sure we'd see much of an event as far as ON earth effects.
- tomatotomato37 8y agoBoth the sun and the distance's involved are massive, so besides the scientific observations nothing will change. You would need something massive like a brown dwarf that's already near the fusion point to really screw up the sun The voyage the planet takes through the solar system might drag some asteroids with it however, which could lead to some fun
- ChuckMcM 8y agoNapkin math (aka pure speculation) suggests that unless the rogue planet hit the star directly and at an angle that could send ejecta our way, the results would be more observational than catastrophic. The Earth is roughly 333,000 times less massive than the Sun. Think of it this way, If an asteroid hit the Earth that was, in relative terms, the size of the earth relative to the sun, it would be about 1/3 the size of Ceres. Everything on Earth would die but the other planets would probably not notice. Given that the surface of the Sun can be treated, to a first approximation, as a fluid, an impact that was perpendicular to the surface would likely have the same characteristics of a milk drop. Which is to say a large wave would race away from the impact point and the collapsing of that wave in would eject a bit of coronal mass roughly equal to 1% of the mass of the impactor (note this makes a big, and unsupported, assumption about the viscosity of the solar corona.) The only scary bit comes if the rogue planet enters the solar system slightly off the plane of the ecliptic and hits the Sun in a glancing blow. In such a scenario it could transfer a huge amount of momentum into the coronal mass which would then immediately begin to head away from the Sun. If the Earth were in the path of that mass it would probably wipe everything out after blowing off our atmosphere. This wouldn't be good for the rogue planet either, which would probably enter a hyperbolic orbit and shoot away from the solar system on a new trajectory. In the unfortunate circumstance that this "coronal braking maneuver" was sufficient to slow the planet enough to be captured by the Sun, the remaining planets would get to witness periodic brushes with the Sun by the rogue planet until it had lost enough energy to fall into the Sun. That would be mitigated if the orbit it fell into pulled it by Jupiter or another large planet which, by virtue of its gravity circularize the orbit sufficiently that it would not come near the corona on future orbits.
- skookumchuck 8y agoRemember when that comet crashed into Jupiter? Not much happened, even on Jupiter's surface.
- sudhirj 8y agoThere's an exploration of that in book 2 of the Three Body Problem / The Dark Forest. Don't remember exact details, but I think it posited the destruction of the inner solar system, mostly due to solar wind both roasting the inner planets, and slowing them down - which causes more planets to fall into the sun in a chain reaction.
- GuB-42 8y agoIt sounds like a perfect question for XKCD's what-if? (https://what-if.xkcd.com/ https://what-if.xkcd.com/) Too bad it isn't regularly updated anymore.
- drdeadringer 8y agoI can't help but think of how the various Star Trek series handled rogue planets... and then later on how IRL science delved into rogue planets as more of a reality than previously realized.
- beamatronic 8y agoCould you provide an example? I don’t recall such an episode.
- hermitdev 8y agoI dont recall the season or episode name, but there was an episode in Voyager that involved a rogue planet that was involved in some sort of ancestral hunting ritual.
- pmontra 8y agoI think it's this one from Enterprise https://m.imdb.com/title/tt0572231/plotsummary?ref_=m_tt_ov_pl https://m.imdb.com/title/tt0572231/plotsummary?ref_=m_tt_ov_...
- clouddrover 8y agoMemory Alpha has a page on Star Trek episodes which feature rogue planets: http://memory-alpha.wikia.com/wiki/Rogue_planet http://memory-alpha.wikia.com/wiki/Rogue_planet
- baxtr 8y ago“It is unclear how plant life could survive on Dakala. One scene, however, shows the surface covered in the dim light of a nearby star, perhaps supplying enough energy for some form of photosynthesis. Another theory, from the Star Trek Encyclopedia (4th ed., vol. 1, p. 177), is that the plant and animal life was supported by the surface heat from volcanic vents.“ From http://memory-alpha.wikia.com/wiki/Dakala http://memory-alpha.wikia.com/wiki/Dakala
- 8y ago
- wrycoder 8y agoIf this is recent information, how does it bear on dark matter, i.e. machos? An excellent read, btw.
- antognini 8y agoThis is not super recent information. There have been estimates that there are about as many rogue planets as stars since 2011. There's still a pretty wide variation in the estimate of the number of rogue planets from study to study, so the frequency is pretty uncertain. But even if the numbers are on the high side, it's not anywhere close to explain dark matter. Supposing that there are 10 Jupiter mass planets for every star, that would only increase the luminous mass of the Galaxy by 1%. Dark matter accounts for more than ten times the mass of the Galaxy as luminous matter.
- SubiculumCode 8y agoNot a physicist. If napkin calculation goes, that's 1000 Jupiters per star. Is that really improbable? There is a lot of space outside of solar system radii.
- antognini 8y agoI think it would require more like 10,000 Jupiters per star to account for dark matter in the Galaxy. The issue is that these microlensing surveys put an upper bound on the number of rogue Jupiters that can be floating around and this bound is much less than 10,000 per star.
- Eesais2e 8y agoCan microlensing account for the whole continuum of black hole sizes that might be floating around in the galactic halo?
- ataturk 8y agoWhy would we visit forbes.com to learn about astronomy?
- ComputerGuru 8y agoA true scholar seeks knowledge wherever it may be found.
- paulie_a 8y agoBecause Forbes actually has quality in depth reporting on a variety of topics.
- gnulinux 8y agoIs there a specific reason we shouldn't, do you think?
- King-Aaron 8y agoBecause it just so happens that Forbes has an article about astronomy.
- bencollier49 8y agoYes, but it's probably rubbish clickbait. They locked me out of the site when I opted out of tracking. Good riddance and I look forward to their receiving a hefty fine from the EU for GDPR non-compliance.
- King-Aaron 8y agoThe title doesn't seem to embellish the article, and others are noting that the author is credible. Sorry to hear that you were blocked from being able to read it.
- akvadrako 8y agoThe author is not credible - he posts almost every day and he doesn't understand half of it. It's just fluff.
- perl4ever 8y agoBased on the inverse correlation between star size and frequency, this doesn't surprise me at all. It seems like there is an obvious further inference to make - people have debated whether life originated on earth or not. Given that the vast majority of planets do not have a star, and given that we know there are chemotrophs even on Earth that prove it is possible to live without a sun, it seems overwhelmingly likely that life came from one of these rogue planets that was large enough to retain enough heat underground for the evolution of life over the first few billion years of the universe. That would also neatly explain why evidence of life appeared so soon after the Earth became solid.
- havemylife 8y agoI'm not discounting the possibility of life on Earth originating from somewhere other than Earth. However, why would the early conditions of Earth not be sufficient for life to begin over say any other object in space with the base elements for life? How life began is obviously still an unanswered question, but if the conditions for self replicating molecules were sufficient early on for Earth, I'm not sure why billions of years would be needed for life to form versus several hundred million years.
- toong 8y agoEarth needed ~ 2 billion years for life to start. Frequent solar winds - especially in the first few billion turbulent years of the universe - basically sterilize planets and the whole 2-billion-year counter gets reset to 0. Planets that exist without a solar system, but do retain sufficient heat, might have been out of solar winds harm ?
- Peaker 8y agoLife on Earth started within a few hundred million years, not 2 billion years.
- havemylife 8y agoI'm by no means well informed on these topics, but I'm unsure where you're getting your 2 billion year estimate. Furthermore I thought that Earths magnetic field shielded from solar radiation, and additionally that there's a significant amount of radiation in space anyways. Further questioning I have though is, does solar radiation penetrate through ocean water? What radiation is between solar systems or what rogue planets would likely encounter, and how that effects single cell life, amino acids, organic compounds, and any other building blocks to life?
- itronitron 8y agoInterstellar travel now seems a lot more hazardous than it did before. To quote one of my TAs in college, "it's the stuff you can't see that gets you" ...
- lev99 8y agoThe article states that planets may outnumber stars 100,000 to 1. The Milky Way has 4E^11 stars. It has an upper estimate of 4E^16 planets. It has a lowest estimate diameter of 100kly. It has an estimated thickness of 2kly. It's lower estimate volume is 63,000 kly^2. ----------------------------- If planets are uniformly disrupted (they surely aren't), there are ~17 planets in every cubic light year. Sure, that's a hazard.
- nabla9 8y ago> ~17 planets in every cubic light year. The change of hitting one while traveling one light year is in the order of 10e-16.
- mrarjen 8y agoExactly, and I saw that when the Andromeda Galaxy collides with ours, it's unlikely many planets/systems will be colliding with one another.
- boznz 8y agoNever really understood how galaxies can collide if space has been expanding since the big bang and everything is moving apart
- ben_w 8y agoIt goes both ways depending on distance. Expansion is exponential (ish), gravity is inverse-square [1]. Only the few that happened to be close enough that gravity is more significant than expansion can collide. [1] at least in Newtownian physics. The argument is geometry, so I suspect but am not qualified to say it isn’t exactly inverse square in GR.
- afterburner 8y agoNew 4x games should now include plenty of planets between star systems. Cold and still, but potential mining boons and refueling bases.
- ianai 8y agoAnd I demand Star Trek TNG be reran with scientifically appropriate visits to rogue planets. /s
- lebrad 8y agoThe Founder's homeworld on Deep Space Nine was a rogue planet
- Murdodc089 8y agoI'm sure someone is already working on a mod for Stellaris that does exactly what you describe.
- flurdy 8y agoWould make a mess of the hyperlanes network in Stellaris...
- dandr01d 8y ago[deleted]
- King-Aaron 8y agoRoger
- deleted 8y ago[deleted]
- kamaal 8y agoThis sort of space real estate is the biggest hindrance to developing long term interstellar traveling tech. With so many asteroids and planets lying around. There is no real motivation to travel very far distances for resources. Once you start mining the first set of asteroids and settling your race in space. You could grow organically, and at some point mine a terrestrial planet. At that point you have so many resources at your disposal it doesn't really make much sense to move out to very large distances unless for science or your population is just multiplying beyond control.
- lmm 8y agoHas the IAU come around to a sensible definition of "planet", or are these officially non-planets?
- doikor 8y agoCurrent definition requires the object to be orbiting the Sun (and only the Sun not other stars) so by IAU definition these are not planets. > A "planet" is a celestial body that: (a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, and (c) has cleared the neighbourhood around its orbit. > A "dwarf planet" is a celestial body that: (a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, (c) has not cleared the neighbourhood around its orbit, and (d) is not a satellite. > All other objects, except satellites, orbiting the Sun shall be referred to collectively as "Small Solar System Bodies".