Three planets in habitable zone of nearby star (w/ video)

Jun 25, 2013
3 planets in habitable zone of nearby star
This artist's impression shows the view from the exoplanet Gliese 667Cd looking towards the planet's parent star (Gliese 667C). In the background to the right the more distant stars in this triple system (Gliese 667A and Gliese 667B) are visible and to the left in the sky one of the other planets, the newly discovered Gliese 667Ce, can be seen as a crescent. A record-breaking three planets in this system are super-Earths lying in the zone around the star where liquid water could exist, making them possible candidates for the presence of life. This is the first system found with a fully packed habitable zone. Credit: ESO/M. Kornmesser

(Phys.org) —A team of astronomers has combined new observations of Gliese 667C with existing data from HARPS at ESO's 3.6-metre telescope in Chile, to reveal a system with at least six planets. A record-breaking three of these planets are super-Earths lying in the zone around the star where liquid water could exist, making them possible candidates for the presence of life. This is the first system found with a fully packed habitable zone.

Gliese 667C is a very well-studied star. Just over one third of the mass of the Sun, it is part of a triple star system known as Gliese 667 (also referred to as GJ 667), 22 light-years away in the constellation of Scorpius (The Scorpion). This is quite close to us—within the Sun's neighbourhood—and much closer than the star systems investigated using telescopes such as the planet-hunting Kepler space telescope.

Previous studies of Gliese 667C had found that the star hosts three with one of them in the . Now, a team of astronomers led by Guillem Anglada-Escudé of the University of Göttingen, Germany and Mikko Tuomi of the University of Hertfordshire, UK, has reexamined the system. They have added new HARPS observations, along with data from ESO's Very Large Telescope, the W.M. and the Magellan Telescopes, to the already existing picture. The team has found evidence for up to seven planets around the star.

These planets orbit the third fainter star of a triple star system. Viewed from one of these newly found planets the two other suns would look like a pair of very visible in the daytime and at night they would provide as much illumination as the . The completely fill up the habitable zone of Gliese 667C, as there are no more stable orbits in which a planet could exist at the right distance to it.

This diagram shows the system of planets around the star Gliese 667C. A record-breaking three planets in this system are super-Earths lying in the zone around the star where liquid water could exist, making them possible candidates for the presence of life. This is the first system found with a fully packed habitable zone. The relative approximate sizes of the planets and the parent star are shown to scale, but not their relative separations. Credit: ESO

"We knew that the star had three planets from previous studies, so we wanted to see whether there were any more," says Tuomi. "By adding some new observations and revisiting existing data we were able to confirm these three and confidently reveal several more. Finding three low-mass planets in the star's habitable zone is very exciting!"

Three of these planets are confirmed to be super-Earths—planets more massive than Earth, but less massive than planets like Uranus or Neptune—that are within their star's habitable zone, a thin shell around a star in which water may be present in liquid form if conditions are right. This is the first time that three such planets have been spotted orbiting in this zone in the same system.

This video is not supported by your browser at this time.
This video shows the orbital motions of the planets around the star Gliese 667C. Three of these planets are super-Earths orbiting in the habitable zone where liquid water may exist. The orbit of the planet Mercury in the Solar System is included for scale. As Gliese 667C is fainter and cooler than the Sun the habitable zone is much closer to the star than in the Solar System. Credit: Rory Barnes/ESO

"The number of potentially habitable planets in our galaxy is much greater if we can expect to find several of them around each low-mass star—instead of looking at ten to look for a single potentially habitable planet, we now know we can look at just one star and find several of them," adds co-author Rory Barnes (University of Washington, USA).

Compact systems around Sun-like stars have been found to be abundant in the Milky Way. Around such stars, planets orbiting close to the parent star are very hot and are unlikely to be habitable. But this is not true for cooler and dimmer stars such as Gliese 667C. In this case the habitable zone lies entirely within an orbit the size of Mercury's, much closer in than for our Sun. The Gliese 667C system is the first example of a system where such a low-mass star is seen to host several potentially rocky planets in the habitable zone.

The ESO scientist responsible for HARPS, Gaspare Lo Curto, remarks: "This exciting result was largely made possible by the power of HARPS and its associated software and it also underlines the value of the ESO archive. It is very good to also see several independent research groups exploiting this unique instrument and achieving the ultimate precision."

And Anglada-Escudé concludes: "These new results highlight how valuable it can be to re-analyse data in this way and combine results from different teams on different telescopes."

Explore further: How common are earths around small stars?

More information: Research paper

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Requiem
3 / 5 (10) Jun 25, 2013
This article would be a lot better if it included another paragraph or two detailing the basic derived properties of the 3 planets.

That being said, what a thought-provoking discovery. So many differences! These planets will be tidally locked, which is far from a deal-breaker for life as we know it, and I can imagine situations within the vicinity of the terminator that would be highly dynamic, perhaps making the pace of evolution here on Earth look quaint. The planet itself provides a gradient of challenged for life to overcome, and also a fallback position to start from if it fails.

Then there's the extremely close proximity of the planets, and the possibility that a planet that's only days or weeks away using 1960's technology could be habitable for any intelligent life that arose on any of them.

Add to this the fact that these small stars have vast lifetimes. Great topic.
Matthewwa25
2.3 / 5 (9) Jun 25, 2013
There's probably billions of habitual planets.
Q-Star
3.9 / 5 (18) Jun 25, 2013
There's probably billions of habitual planets.


A bad habit it is, but a hard one to break.
MandoZink
5 / 5 (4) Jun 25, 2013
There's probably billions of habitual planets.

And for that we can be grateful. They would hardly be habitable otherwise.
GSwift7
3 / 5 (11) Jun 25, 2013
That being said, what a thought-provoking discovery. So many differences! These planets will be tidally locked


No, they probably aren't tidally locked.

Mercury isn't tidally locked. It was once thought to be locked, but it has a 3:2 resonant rotation, with 3 rotations per 2 orbits.

Also, tidal locking is dependent on the ratio of the mass between the two objects. These planest are bigger than Mercury and the star is much smaller than our sun. That would make them much less likely to be tidally locked. If thier oribts are sufficiently eliptical then they are certainly not tidally locked, as in the case of Mercury.

This is a really big story. These are actually close enough and the star is dim enough that we will be able to get a lot of data about these planets, even with existing telescopes.
pauljpease
5 / 5 (3) Jun 25, 2013
Awesome! I hope we discover life out there in my lifetime. If we do I think there's a chance that humanity will find a reason to survive...so we can take our place among the stars.
Torbjorn_Larsson_OM
5 / 5 (4) Jun 25, 2013
Nearly 5 of Gliese 667C 6-7 planets lie within its narrow habitable zone. (See the HEC news release.)

We can expect to see up to 4-5 habitables around larger stars, which are fewer and harder to see small planets around, when those stars are properly surveyed.

And since I love to hate the idiotic Rare Earth idea, it makes me happy to see analogously idiotic "perfect Earth in a perfect system" magic incantations take a huge hit.

@Requiem: Go to the Habitable Exoplanets Catalog news release, it has the data (except updates on the star as of yet). The star is "less than 2 Gyr" as of yet, but Earth had life then.

Yes, when people look into tidal lock, the largest difference is purely a pattern of heat distribution. But it isn't a severe problem in most cases AFAIK.

Even then, a thicker atmosphere moderates the global temperature differentials and winds to less than what we can see locally on Earth. A thicker atmosphere is better for Gliese 667C f to be habitable anyway.
Protoplasmix
1.8 / 5 (9) Jun 25, 2013
Looks like a prime candidate for observation with the SKA telescope, when/if it's built. Terrestrial signals from 1991 would be arriving there now. So much for first impressions :)
Osiris1
2 / 5 (8) Jun 26, 2013
And that system will be around for many billions of years. Nice if all three or all five planets have or could host life. Now we need a warp drive to get there.
Fleetfoot
4 / 5 (4) Jun 26, 2013
And that system will be around for many billions of years. Nice if all three or all five planets have or could host life. Now we need a warp drive to get there.


Even at 1% of the speed of light, it will only take 2200 years to put a probe into orbit in the system, the blink of an eye in astronomical and evolutionary terms.
VendicarE
5 / 5 (5) Jun 26, 2013
I Call Dibs on Planet 4.

VendicarE
5 / 5 (4) Jun 26, 2013
"Even at 1% of the speed of light" - Fleefoot

Ya, but with Martini and Rossi's E-Cat Stardrive it will only take negative 1.5 seconds.

I'm sure it is true.Italian science is never wrong.

VendicarE
4 / 5 (2) Jun 26, 2013
"Now we need a warp drive to get there" - Osirus

No longer. Thanx to the new Star Trek movie, all we need is one of them TransWarp Transporter's that Kahn used to beam himself to Klingon for no particular reason.

But then you have to ask yourself why the Admiral needed a destroyer class starship, and fancy schmancy photon Torpedo's, and why he ordered them loaded onto the Enterprise when he could have just materialized them above their target with the same transporter he used to get to Klingon.

And why was Praxis already in pieces?

Shit writing. Shit movie, for a low IQ American audience who forget every plot hole with the next explosion.

This pretty much sums it all up...

http://cdn.mix4fu...ulfi.gif
Bog_Mire
1 / 5 (5) Jun 26, 2013
Yes, dog pissing itself when barking sums quite a lot up actually

The Gleiseans are the ones who messed with GWB Jr's head then? Or most likely candidate so far?
Egleton
3 / 5 (10) Jun 26, 2013
I wonder what it is like to live in a star system where you find out early on that your planet is not the only inhabited one?
Does that make everyone paranoid or excited?
Does the thought of a sister planet just over there, alive and ripe for the taking, encourage space travel?
All we have got is a barren moon as a stepping stone, a lot of imagination and lethal exponential curves to encourage us up and over.
The choice is not between a hazardous life in the void and a safe life here at the bottom of the well, but between certain extinction here and a potentially salubrius life in habitats of our own design.
GSwift7
2.5 / 5 (8) Jun 26, 2013
Does that make everyone paranoid or excited?
Does the thought of a sister planet just over there, alive and ripe for the taking, encourage space travel?


I don't think it would matter much. Any intelligent species would probably go through the same kind of slow development of culture and civilization that we did. So, they would look at the night sky and dream just like we did. By the time technology allowed them to actually contemplate space travel as a reality, they would likely already know a bit about the planet next door. Then, a couple generations later, space travel would be so common that it doesn't make news headlines any more (just like us). So, for example, if Mars had been habitable, would it have made much difference for us? I think we still wouldn't have tried space travel until the late 20th century. Once you reach that tech level, you grow really fast anyway, so I don't think it would matter. What difference would a couple decades make?
no fate
5 / 5 (1) Jun 26, 2013
And that system will be around for many billions of years. Nice if all three or all five planets have or could host life. Now we need a warp drive to get there.


Even at 1% of the speed of light, it will only take 2200 years to put a probe into orbit in the system, the blink of an eye in astronomical and evolutionary terms.


Very true, but it is an eternity for the life of any machine.

As far as the warp drive, I think the ability to detect objects the size of a golf ball at a distance of several AU will be required before we send anything, manned or not into space at or beyond speed c.
Fleetfoot
5 / 5 (3) Jun 26, 2013
And that system will be around for many billions of years. Nice if all three or all five planets have or could host life. Now we need a warp drive to get there.


Even at 1% of the speed of light, it will only take 2200 years to put a probe into orbit in the system, the blink of an eye in astronomical and evolutionary terms.


Very true, but it is an eternity for the life of any machine.


Attrition is of course the problem hence self-repair capability would essential and the limitation is then the amount of energy available for that maintenance. One suggestion is that the probe is spun up on launch and extracts energy by interaction with the galactic magnetic field but there are many possibilities.

That same technology would then allow a probe to split into two and self-repair each half using local materials. Self-replicating probes are the only logical approach to exploring the galaxy:

http://en.wikiped..._machine
no fate
5 / 5 (1) Jun 26, 2013
Self replicating and self repairing tech would have to be the answer, I agree. My opinion on that one is that nanoscale machines emulating cellular reproduction are the way to go with each type of "cell" being function specific just like the human body. It is the only way I can imagine being able to clear all of the hurdles associated with this type of venture. Quantum processing is a must.

Even with the pace of advancement of tech today, I would still put us at least 3-500 years away from producing working technology of this nature, but I don't see anything else as capable of dealing with all of the variables, and this approach could use particle flux as a power source because of its cellular nature.
Fleetfoot
5 / 5 (1) Jun 26, 2013
Self replicating and self repairing tech would have to be the answer, I agree. My opinion on that one is that nanoscale machines emulating cellular reproduction are the way to go with each type of "cell" being function specific just like the human body. .. Even with the pace of advancement of tech today, I would still put us at least 3-500 years away from producing working technology of this nature


The key technology is AFM:

http://www.resear...ms.shtml

Put an AFM head onto this and you have a mobile construction vehicle:

http://phys.org/news7438.html

http://phys.org/n...232.html

http://www.mrsec....e-wheels

I think that aspect should be achievable by the end of this century.

For processing, graphene has advantages both in performance and its 2D structure which can be incorporated into the mechanical structure. Low power and mass are the key aspects, MIPS aren't important, there's no rush ;-)
macdiva524
4.3 / 5 (3) Jun 26, 2013
The concept of neighboring planets with intelligent and technologically capable inhabitants coexisting in mutual admiration and with the feeling that they are lucky to have planetary brothers and sisters is absurd. If we human's use our own history from early mankind to present as example in supposition of how beings in twin planetary civilizations would relate to one another, we may find them either in constant conflict or one civilization having conquered and the other.
That is if they are even of a similar biological form. No one has even mentioned that although they are in the "Goldilock's Zone" they may be neither carbon based nor oxygen breathers, as we are, nor may the inhabitants of the neighboring planets be of mutual bio evolutionary make up. They may possibly not recognize the other as intelligent nor even as living creatures.

As someone referred to Star Trek above, think back to the original series when the crew discovered a silicon based, intelligent life form.
Neinsense99
3.2 / 5 (11) Jun 26, 2013
@Fleetfoot wrote, in part: "The key technology is AFM"

Actually, the key is making sure it has 8 wheels, so it can be called an AFM/8-track, just to give the older technophiles a little nostalgic flashback of sorts.
Requiem
1.7 / 5 (6) Jun 27, 2013
The concept of neighboring planets with intelligent and technologically capable inhabitants coexisting in mutual admiration and with the feeling that they are lucky to have planetary brothers and sisters is absurd.


Who suggested that?

And statistically speaking, it would be improbable, based upon the only analog we have, ourselves, that two intelligent species would evolve within half a million years of each other on different planets, even in the same system. Any more and you'd have Homo Sapiens versus Australopithecus at BEST, hardly a fair "fight" or even worthy of any more moral regard than we give to, say, chimpanzees. If there were nothing more than chimps on the forest world of Mars, I don't think we'd have too many qualms about moving on in.
Requiem
1.7 / 5 (6) Jun 27, 2013
Cont.

This extends to any other sort of life form you can imagine, by the way. Unless two intelligent species emerge within the short time it takes them to develop civilization and then mount a mission with a similar scale to Apollo, which is pretty unlikely, there is never any conflict to be had.
Fleetfoot
5 / 5 (3) Jun 27, 2013
This extends to any other sort of life form you can imagine, by the way. Unless two intelligent species emerge within the short time it takes them to develop civilization and then mount a mission with a similar scale to Apollo, which is pretty unlikely, there is never any conflict to be had.


The same applies on the larger scale too. At 1% of the speed of light, it would only take around 10 million years to build a netork spanning the galaxy. That's a short time compared to the age of the galaxy so unless we are the only extant technological species, it is likely that such a network would have been built by whatever species evolved to our current level first. All others will start moving out and probably encounter that ancient network within a few systems from their home world.
GSwift7
2 / 5 (6) Jun 27, 2013
Who suggested that?

And statistically speaking, it would be improbable, based upon the only analog we have, ourselves, that two intelligent species would evolve within half a million years of each other


Unless there was a common source for both, which spread from one planet to the other? Think about Neandertal and Homosapien, two species who evolved together on the same planet.

such a network would have been built by whatever species evolved to our current level first.


Or, probably more likely, whichever species is evoloved to the highest level amongst space-faring species. It doesn't matter if you get there first if you aren't able to keep it. Even the most kind and generous species, if evolved to the point that we seem equal to ants compared to them, would be incapable of even having a conversation with us. The most evolved species would judge their own agenda to be more important than any other species, and justifiably so. They would push us aside like dust.
GSwift7
2.7 / 5 (7) Jun 27, 2013
Really, we better hope that we are a fluke, and that intelligent life capable of space travel is exceedingly rare. If not, then the odds are against us being the most intelligent of the bunch. Never mind technological advancement. Technology builds on itself exponentially. We have probably learned more in the last 100 years than we did in the 10,000 years prior to that. An exceptionally smart species should be able to easily surpass the technology of a less intelligent species in short order, no matter how much of a head start the lower species had.

There are three ways it can end well for us:

1-We never meet another space faring species
2-We are the lucky owners of the biggest brains in the galaxy and survive long enough to become as gods compared to the rest
3-There's already a galactic overlord who does not permit interstellar expansion, and doesn't go around wiping people out for fun.

The overlord would need to enforce the three laws of robotics on planets to maintain peace
Maggnus
5 / 5 (2) Jun 27, 2013
Coming back to Earth for a second :), with regard to the tidal locking, it crosses my mind that a planet that is tidally locked around one star would still get the benefit of the other two stars in this system. So, while the "daytime" side would always be facing the brightest/closest/hottest star, the nighttime side would still get "daylight" in varying degrees from the other two stars. Make for a very interesting sci-fi concept if nothing else!
Golden_Age_Begins
not rated yet Jun 27, 2013
If these planet's aren't tidally locked it may mean very severe effects for their surface geology. I am not sure how far apart they are from each other, but it is definitely something to think about when considering the possibility of life developing there. A very active system can be just as dangerous for such development as a less active one.
Fleetfoot
5 / 5 (3) Jun 27, 2013
such a network would have been built by whatever species evolved to our current level first.


Or, probably more likely, whichever species is evoloved to the highest level amongst space-faring species. It doesn't matter if you get there first if you aren't able to keep it.


Consider that our technology has been developed entirely in the last few centuries but that is too short a time for any significant evolution. In fact can we say Einstein was any more intelligent than Pythagoras for example?

If we are the second race to reach this level, those who came first we probably at this level several billion years ago so they would have been monitoring our development since we were single-celled. How could we out-engineer them when they can copy our every new idea?

The most evolved species would judge their own agenda to be more important than any other species, and justifiably so. They would push us aside like dust.


And yet we exist, we have not been pushed aside.
GSwift7
1.8 / 5 (5) Jun 28, 2013
And yet we exist, we have not been pushed aside


Yep, so what does that tell us?

If these planet's aren't tidally locked it may mean very severe effects for their surface geology. I am not sure how far apart they are from each other


The two biggest factors that would cause tidal heating are large moons (like us) or a highly eliptical orbit around the star (like mercury). The planets shouldn't have much influence on each other's tides. If you looked at a photograph of the system from above, these planets would look like tiny specks with a large distance between them. The scale of planetary systems is difficult to imagine, especially since the diagrams we commonly use are never to scale. For example, Venus and Mars are tiny dots in our sky. The planets in the system above wouldn't appear much bigger, though they would be much brighter.
Fleetfoot
5 / 5 (1) Jun 28, 2013
And yet we exist, we have not been pushed aside


Yep, so what does that tell us?


Only that, if there is another technological species in the galaxy, they have chosen not to "push us aside like dust". We tend to think in Star Trek terms of species at approximately the same level, evolving in parallel but the reality is that species would arise separated by very large times gaps. If they had wanted to colonise our planet, it would have happened long before the first primates evolved, never mind homo sapiens.
Neinsense99
3 / 5 (10) Jun 28, 2013
And yet we exist, we have not been pushed aside


Yep, so what does that tell us?


Only that, if there is another technological species in the galaxy, they have chosen not to "push us aside like dust". We tend to think in Star Trek terms of species at approximately the same level, evolving in parallel but the reality is that species would arise separated by very large times gaps. If they had wanted to colonise our planet, it would have happened long before the first primates evolved, never mind homo sapiens.

That's quite likely, but a civilisation near our level of development is not prohibited, especially if a celestial event affected a region of the galaxy leveling the playing fields at some point. I'd expect primitive or much more advanced, but it's also more likely that we'd notice similar communication technology and be noticed by similar technology.
GSwift7
1.8 / 5 (5) Jun 28, 2013
they have chosen not to "push us aside like dust".


Or they just haven't gotten around to it yet. If we ever start to venture out amongst the stars, that could change.

We tend to think in Star Trek terms of species at approximately the same level, evolving in parallel but the reality is that species would arise separated by very large times gaps


I guess it depends on how common intelligent life is. If it is very common, then perhaps there's a steady stream of new intelligent species popping up all over the place.

Based on Earth's history, I'd say life may be common, but civilization may be rare. The dinosaurs and aquatic life had millions of years and never built tools.

Wouldn't that be a hoot? Life everywhere, and WE are the smartest ones?
Fleetfoot
5 / 5 (1) Jun 29, 2013
they have chosen not to "push us aside like dust".


Or they just haven't gotten around to it yet. If we ever start to venture out amongst the stars, that could change.


One of our probes arriving in a distant star system at 1% c could be easily vapourised by a sheet of plastic in its path and if we connect to their network, there's no reason for us to expand our (and fight for bandwidth on inter-stellar links) beyond our local sphere.

If it is very common, then perhaps there's a steady stream of new intelligent species popping up all over the place.


The more there are, the higher the average rate and the earlier he first would have appeared. It just makes it more likely that there is an extant network.

The dinosaurs and aquatic life had millions of years and never built tools.


Exactly. A galaxy full of pond slime or jurassic planets might be highly likely, but we have no idea what conditions prompt the step to technological capability.
philw1776
1.6 / 5 (7) Jun 29, 2013
If the planets are NOT tidally locked given their proximity to the host star, tides would be huge. Tidal force goes not as the square but as the cube of the distance. Any bodies of water on these dim star huggers would scour the land areas as the planet rotated. Worse yet there would be massive volcanic activity as the planet's core and mantle rotation sweeps through the tidal vector. I think a tidally locked planet with all its drawbacks (one side frozen uninhabitable, huge sub-solar storms, terminator temperature equalization winds) is a better candidate for life forms that are mobile.
Requiem
1.7 / 5 (6) Jun 30, 2013
Unless two intelligent species emerge within the short time it takes them to develop civilization and then mount a mission with a similar scale to Apollo, which is pretty unlikely, there is never any conflict to be had.


The same applies on the larger scale too. At 1% of the speed of light, it would only take around 10 million years to build a netork spanning the galaxy.


I don't disagree, but want to point out that an Apollo-scale mission to a planet that's one-fifth of Mercury's orbit away, we can parachute stuff down on, and which can already(or almost) support us to establish a self-sustaining and expanding colony is NOTHING LIKE a massive eon-operating, advanced-civilization-spewing, generation ship that has new planets shooting off their own generation ships within thousands of years of arrival.

I'd say the most obvious difference is that we know one has happened at least one time in the universe. Another would be the relative probability for any given race.
Requiem
1 / 5 (5) Jun 30, 2013
Err, obviously the EXACT Apollo-like mission I described has not taken place, but we have certainly demonstrated the ability to deliver a large amount of infrastructure to a planet in that scenario.

Another difference between this small example I gave and the galactic empire, to fall back on the same small example, is that while "If there were nothing more than chimps on the forest world of Mars, I don't think we'd have too many qualms about moving on in.", I think we'd apply a completely different set of values to the prospect of halting the emergence of new intelligent species on a galactic scale in a systematic way. Again, the two are nothing alike.

There are other challenges facing the empire as well, such as the fact that it could take 100,000 years for messages to travel from central authorities to local ones, any support or trade is infeasible, the motivations begin falling apart for such an empire if the speed of light is a constraint.
Fleetfoot
not rated yet Jul 01, 2013
The same applies on the larger scale too. At 1% of the speed of light, it would only take around 10 million years to build a netork spanning the galaxy.


I don't disagree, but want to point out that an Apollo-scale mission to a planet that's one-fifth of Mercury's orbit away, we can parachute stuff down on, and which can already(or almost) support us to establish a self-sustaining and expanding colony is NOTHING LIKE a massive eon-operating, advanced-civilization-spewing, generation ship that has new planets shooting off their own generation ships within thousands of years of arrival.


Certainly the sort of in-system scenario you consider is entirely different and I don't disagree with your views on that.

What I was describing was not generation ships but low mass, automated light sail probes like Ikaros. Their theoretical maximum is around 2% of c. They can easily build a comms network but human transport is another problem.
Neinsense99
3 / 5 (10) Jul 02, 2013
"Now we need a warp drive to get there" - Osirus

No longer. Thanx to the new Star Trek movie, all we need is one of them TransWarp Transporter's that Kahn used to beam himself to Klingon for no particular reason.

But then you have to ask yourself why the Admiral needed a destroyer class starship, and fancy schmancy photon Torpedo's, and why he ordered them loaded onto the Enterprise when he could have just materialized them above their target with the same transporter he used to get to Klingon.

And why was Praxis already in pieces?

Shit writing. Shit movie, for a low IQ American audience who forget every plot hole with the next explosion.

This pretty much sums it all up...

http://cdn.mix4fu...ulfi.gif

Sorry, Vendicar, I was too busy saving the world to read your comment on Americans and movie explosions. You should see what all that explosion-diving does to my dry cleaning bill!
GSwift7
1.6 / 5 (7) Jul 02, 2013
If the planets are NOT tidally locked given their proximity to the host star, tides would be huge. Tidal force goes not as the square but as the cube of the distance.


That is completely uninformed nonsense.

Gravitational force falls off at the square of distance. There's no exception to this. You are just making stuff up, and it is wrong.

The planets' own gravity would be proportionally larger, acting to stabilize the tides. Just as you see here on Earth, the tides caused by the star are small in the above case as well.
Neinsense99
3 / 5 (10) Jul 02, 2013
If the planets are NOT tidally locked given their proximity to the host star, tides would be huge. Tidal force goes not as the square but as the cube of the distance.


That is completely uninformed nonsense.

Gravitational force falls off at the square of distance. There's no exception to this. You are just making stuff up, and it is wrong.

The planets' own gravity would be proportionally larger, acting to stabilize the tides. Just as you see here on Earth, the tides caused by the star are small in the above case as well.

Woe betide those who are untidy with tides.
Fleetfoot
5 / 5 (2) Jul 02, 2013
If the planets are NOT tidally locked given their proximity to the host star, tides would be huge. Tidal force goes not as the square but as the cube of the distance.


That is completely uninformed nonsense.

Gravitational force falls off at the square of distance. There's no exception to this. You are just making stuff up, and it is wrong.


Tidal forces are the derivative of the gravitational force so go as the inverse cube, his statement is correct:

http://en.wikiped...e#Forces

There's a nice analysis here which also notes the effect in terms of angular size and density:

http://www.npl.wa...w63.html
philw1776
1 / 5 (6) Jul 04, 2013
If the planets are NOT tidally locked given their proximity to the host star, tides would be huge. Tidal force goes not as the square but as the cube of the distance.


That is completely uninformed nonsense.

Gravitational force falls off at the square of distance. There's no exception to this. You are just making stuff up, and it is wrong.

The planets' own gravity would be proportionally larger, acting to stabilize the tides. Just as you see here on Earth, the tides caused by the star are small in the above case as well.


Uh, learn some physics. You should not make authoritative comments when you are ignorant of the facts.

http://en.wikiped...al_force

q.v. mathematical treatment

Varies as cube of distance, oft neglected by those discussing tidal effects.
Worse yet M star HZ planets in rotational resonance (e.g. Mercury...look it up!) with oceans would have them scrape the surfaces clean.

And eliptical orbits would subject such planets to severa

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