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Mysterious Planet May Be Cruising For a Bruising

Soulskill posted about a year and a half ago | from the mark-your-calendars dept.

Space 104

sciencehabit writes "Something is orbiting the bright star Fomalhaut in the constellation known as the Southern Fish, but no one knows exactly what it is. New observations carried out last year with the Hubble Space Telescope confirm that the mysterious object, known as Fomalhaut b, is traveling on a highly elongated path, but they haven't convincingly nailed down its true nature. But if it is a planet, as one team of astronomers thinks, we may be in for some celestial fireworks in 2032, when Fomalhaut b starts to plough through a broad belt of debris that surrounds the star and icy comets within the belt smash into the planet's atmosphere." Meanwhile, astronomers recently announced the discovery of the most Earth-like exoplanet yet seen, which orbits a G-type star, has a radius 1.5 times that of Earth and a year of about 242 days.

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104 comments

Cruising for bruising? (2)

girlintraining (1395911) | about a year and a half ago | (#42558921)

Terrible headline aside, I can only hope this time NASA doesn't dub in canned laughter and slapstick noises as it crashes through the front lawn. The soundtrack during the rover touchdown was just terrible, and the reward for watching a bunch of dudes in starch-white shirts with ties and unkept hair was a crappy over-pixelated image of a leg. I mean, hey, if that's what puts the lotion on all the power to you, but I've been underwhelmed so far.

Re:Cruising for bruising? (-1)

Anonymous Coward | about a year and a half ago | (#42559101)

Terrible headline aside, I can only hope this time NASA doesn't dub in canned laughter and slapstick noises as it crashes through the front lawn. The soundtrack during the rover touchdown was just terrible, and the reward for watching a bunch of dudes in starch-white shirts with ties and unkept hair was a crappy over-pixelated image of a leg. I mean, hey, if that's what puts the lotion on all the power to you, but I've been underwhelmed so far.

yes but then you see the money and prestige they have and you get moist so quit complaining and get me a beer.

Re:Cruising for bruising? (5, Informative)

arisvega (1414195) | about a year and a half ago | (#42560057)

Terrible headline aside

Since there may be others that feel this way, in the case of exoplanets here is "the one", all-inclusive resource [exoplanets.org] that even the professionals in the field make use of and cite.

(For the click-lazy:) "The Exoplanet Data Explorer is an interactive table and plotter for exploring and displaying data from the Exoplanet Orbit Database. The Exoplanet Orbit Database is a carefully constructed compilation of quality, spectroscopic orbital parameters of exoplanets orbiting normal stars from the peer-reviewed literature, and updates the Catalog of nearby exoplanets."

Access is granted to all data, and I (hopefully along with other slashdotters) am willing to "translate" from the scientific jargon if something sounds too specialized.

25 Ly away (5, Informative)

richardoz (529837) | about a year and a half ago | (#42558925)

For the observable time of 2032, this means it already happened.

Re:25 Ly away (5, Insightful)

Anonymous Coward | about a year and a half ago | (#42559001)

_Everything_ has already happened by the time you've seen it. So what?

Re:25 Ly away (5, Funny)

magarity (164372) | about a year and a half ago | (#42559217)

_Everything_ has already happened by the time you've seen it on Slashdot. So what?

Re:25 Ly away (4, Funny)

fredrated (639554) | about a year and a half ago | (#42559227)

I knew a physics undergrad that had an existential crisis when he realized everything he sees happened in the past.

Re:25 Ly away (4, Funny)

EnsilZah (575600) | about a year and a half ago | (#42560881)

Funny, I went to art school and I'm often frustrated by the fact that most of the stuff I see hasn't happened yet.

Re:25 Ly away (3, Insightful)

Anonymous Coward | about a year and a half ago | (#42559031)

Minkowski spacetime does not work that way. There is no "already" in relativity.

Re:25 Ly away (5, Funny)

Ol Biscuitbarrel (1859702) | about a year and a half ago | (#42559117)

_Everything_ has already happened by the time you've seen it. So what?

First post!

Re:25 Ly away (1)

fredrated (639554) | about a year and a half ago | (#42559215)

lol!

Re:25 Ly away (1)

CaptSlaq (1491233) | about a year and a half ago | (#42559221)

Sublime wit. Oh for mod points.

Re:25 Ly away (2)

girlintraining (1395911) | about a year and a half ago | (#42559295)

First post!

In about 25 years, someone will read this and maybe find it funny. :P

Re:25 Ly away (4, Interesting)

arth1 (260657) | about a year and a half ago | (#42559801)

Minkowski spacetime does not work that way. There is no "already" in relativity.

Correct. I find that most people have a very hard time grasping that time is a local phenomenon, and that there is no universal clock that ticks for both us and distant space. We observe time everywhere as linear, so we think it is both linear and universal.

Words like "since" and "then" can only apply to our local time, and no time has passed "since" the light left the distant star - that "since" is only valid in our time frame, not outside our cone of causality.
Words like "light year" and "light minute" add to the confusion, because in our Newtonian frame of mind we then think that "the" time actually ticks when light goes from A to B, but there is no "the" time.

As Einstein said, "I came to realize that time itself is suspect".

Re:25 Ly away (5, Funny)

jxander (2605655) | about a year and a half ago | (#42559867)

I haven't had nearly enough coffee for this discussion.

Re:25 Ly away (1)

girlintraining (1395911) | about a year and a half ago | (#42560447)

I haven't had nearly enough coffee for this discussion.

I only get that feeling when someone brings up politics before noon.

Re:25 Ly away (1)

dwye (1127395) | about a year and a half ago | (#42563093)

I haven't had nearly enough coffee for this discussion.

I haven't had nearly enough LSD for this discussion.

Re:25 Ly away (2)

swalve (1980968) | about a year and a half ago | (#42559913)

Words like "since" and "then" can only apply to our local time, and no time has passed "since" the light left the distant star - that "since" is only valid in our time frame, not outside our cone of causality.

If no time passed since it left the star, why did it take so long to get here?

Re:25 Ly away (2)

the biologist (1659443) | about a year and a half ago | (#42560201)

No time has passed for the light since it left the star. Time has passed for the star since the light left it.

Re:25 Ly away (2)

arth1 (260657) | about a year and a half ago | (#42560451)

No time has passed for the light since it left the star. Time has passed for the star since the light left it.

(A) is true. (B) is true if you can define a time on the remote star after the light left the star. From here, we can't. What if a wandering black hole eats/ate the star or flings/flung it at near relativistic speeds? That would change their local time rate.

Re:25 Ly away (1)

the biologist (1659443) | about a year and a half ago | (#42561663)

I can define a time on that remote star easily. A black hole eating the star or flinging it at near relativistic speeds doesn't really cause a problem with the existence of time progressing, only of the rate of progression of time. I cannot tell how much time has passed for that star, only that it has.

Re:25 Ly away (2)

arth1 (260657) | about a year and a half ago | (#42560215)

If no time passed since it left the star, why did it take so long to get here?

You're begging the question by presupposing "so long".

In what time frame "did it take so long"?
We know nothing about the remote time frame (and they know nothing about ours - the two are not linked).
In our time frame, the light just arrived.
In the light's time frame, no time passed, because it moved at the speed of light, i.e. with infinite time dilation.

A light year is a distance - how far something would hypothetically travel by Newtonian physics going at 299,792.458 km/s for a year. However, Newtonian physics aren't valid for relativistic speeds and distances. It becomes more and more inaccurate as speed increases (due to time dilation), and you cannot reverse it to extract the time from the distance. Because, whose time?

Re:25 Ly away (0)

Anonymous Coward | about a year and a half ago | (#42560551)

Because, whose time?

Well, if you applied common sense to the original question, instead of trying to get all philosophical, you'd be able to realize that the answer to "whose time" is very easy to figure out - the only one who'se time actually matters here is that of the observer, and the one asking the question. You know - the person for whom time is actually still passing. Unless you're trying to imply that an observer at a star 25 lightyears away would be able to blink their laser pointer at us and have a real-time conversation without 25-year delays, then time does pass, and since time delays have already been shown to happen with such things as the mars rovers, yeah, time does pass from an absolute, observable perspective. Even if you don't like it because it isn't all philosophical and crap.

Re:25 Ly away (2)

arth1 (260657) | about a year and a half ago | (#42560921)

Well, if you applied common sense to the original question, instead of trying to get all philosophical, you'd be able to realize that the answer to "whose time" is very easy to figure out - the only one who'se time actually matters here is that of the observer, and the one asking the question. You know - the person for whom time is actually still passing.

In which case, what we see is happening now. Cause that's our time frame.
It did not happen 25 years ago, because that wouldn't be in our time frame.

Unless you're trying to imply that an observer at a star 25 lightyears away would be able to blink their laser pointer at us and have a real-time conversation without 25-year delays, then time does pass, and since time delays have already been shown to happen with such things as the mars rovers, yeah, time does pass from an absolute, observable perspective.

You can only say something about the round-trip time from that, not the actual time flow. You can observe that it took 50 years to get a reply, but that doesn't mean that the signal took 25 years one way. There is no universal time for those 25 years to pass in.
How long something takes one way is meaningless. When a signal gets either there or here, it always arrives now.

Think of it as a black box you put a letter in. It stays locked for 50 days, and then opens with a reply inside it. This is a repeatable observable thing. From that, you cannot say anything about how long delivery took, even if the person replying swears to replying immediately. You may try to game the system, by sending him a clock with a calendar, and ask him to tell you what time it was when he got it. But thing is, 50 days later when you get a reply, it will say that the time on the clock was the same as when he sent it. And even worse, the clock you got back is still showing the same date and time as when you sent it, just a few minutes delayed.

And this does not matter. You can always think about the remote events in your time frame. We see the birth of a remote galaxy as it happens, from our perspective. Which is the only one we have.

Re:25 Ly away (1)

Anonymous Coward | about a year and a half ago | (#42561147)

Translation: You're too caught up in your philosophical bullshit of "NOBODY CAN EVER REALLY KNOW ANYTHING" to give a practical answer, when laying on the crap will make you feel superior and intellectual. You're just as bad as the solipsists.

Re:25 Ly away (2)

icebike (68054) | about a year and a half ago | (#42562223)

Plus One.

The GP sounds like a classical example of Poisonous People [palmbeachpost.com] .

Re:25 Ly away (1)

Anonymous Coward | about a year and a half ago | (#42560087)

No time may have passed for the light. However that doesn't mean that the poor planet is still waiting to get hit by all those comets just because we haven't observed it yet.

Re:25 Ly away (1)

arth1 (260657) | about a year and a half ago | (#42560477)

No time may have passed for the light. However that doesn't mean that the poor planet is still waiting to get hit by all those comets just because we haven't observed it yet.

The word "still" applies to us, not them. We don't know anything about their time progression.

Re:25 Ly away (1)

wonkey_monkey (2592601) | about a year and a half ago | (#42560607)

However that doesn't mean that the poor planet is still waiting to get hit by all those comets just because we haven't observed it yet.

I may have this wrong, but my understanding is:

"Still" and "yet" are very flexible terms here. In our reference frame, we can define a fairly fixed "now" in which we can be fairly sure that the event happened before "now" - but for another observer in the same position as us but moving at a (vastly) different speed, they may not be so sure. Only when we see it can we be certain that there are no reference frames at our position for which the event is yet to happen.

I forget the details, but I read something like the following: if there is an alien in Andromeda at (for simplicity's sake) a fixed distance from me, he could calculate his current "now" to correspond with my 2013. If he takes a single step further away from us (or is closer?), his now will "bend" to coincide with somewhere around the 1800s. If he steps the other way, it bends into the future. When he stops moving, it's back to 2013. Of course it's not like he can use that to flick through our history, since he still has to wait for the light to get there.

TL:DR; time is to any of the spatial dimensions as x is to 1/x, and many weird things happen.

Re:25 Ly away (0)

Anonymous Coward | about a year and a half ago | (#42560275)

So we are not going to see something special in 2032?

Re:25 Ly away (1)

arth1 (260657) | about a year and a half ago | (#42560621)

So we are not going to see something special in 2032?

Sure we are. From our point of view, there is a planet heading into a debris field that will hit then, our time. That we cannot apply our "now" or "2032" to any instant in their time frame doesn't invalidate our observations and predictions in ours.

Re:25 Ly away (2)

ceoyoyo (59147) | about a year and a half ago | (#42561645)

If you choose a frame of reference you can certainly say that things have happened "already," one thing happens "then" another does, and time has passed "since" an event. Relativity certainly does have an ordering of events (which we like to call causality). The preservation of causality was one of the motivations for relativity.

The OP is correct in stating that this event has "already" happened. It has (or probably has, if nothing intervened), from our particular point of view. His mistake was the smartass tone suggesting that's the ONLY point of view.

Your own position is just as suspect. There certainly is a "the" time, that ticks off 25 years as light goes from Formalhaut to here. It's the one that's indicated on your watch. Not ALL times count the same way, but some definitely do, including the one we're most attached to.

Re:25 Ly away (1)

noshellswill (598066) | about a year and a half ago | (#42562579)

Eau contrario: as words like **since** & **then** apply to an object half-way between earth and our nearest astro-neighbors, the words then surely apply to the next father removed neighbours ... and the next ... until they apply to neighbors half-way between the earth and any physically defined object. For what is true of one-half must be true of the next-half ... as long as you (rationally) believe in rational numbers and counting. Minkowski is fyucked.

Re:25 Ly away (2)

Yoda222 (943886) | about a year and a half ago | (#42565981)

We can solve that by using UTC instead of local time.

Re:25 Ly away (-1)

Anonymous Coward | about a year and a half ago | (#42559435)

I hate people like you. You do not sound smart, you sound like a douche bag.

Re:25 Ly away (1)

Anonymous Coward | about a year and a half ago | (#42559625)

I've often thought this would be an interesting part of a civilization developing FTL travel. Their knowledge of their galaxy/nearby stars could be hundreds or thousands of years old, then they can suddenly see those things "now." Of course, not a whole lot will generally change with a star or planet in just a couple hundred years, but still, it will happen from time to time.

Re:25 Ly away (-1, Flamebait)

nuhasifa (2813723) | about a year and a half ago | (#42561761)

http://www.cloud65.com/ [cloud65.com] like Donald implied I am startled that anyone can earn $7993 in a few weeks on the internet. have you seen this page

Re:25 Ly away (1)

icebike (68054) | about a year and a half ago | (#42561785)

For the observable time of 2032, this means it already happened.

Further, it seems likely that Everything has already happened BEFORE, when we weren't paying attention.

After all, what is the likelihood what we happen to point our telescope at a planet that FOR THE FIRST TIME "starts to plough through a broad belt of debris that surrounds the star"?

(Yes, they did say, after just discovering this planet last week, that it will "for the first time" plough through an belt of debris. Such brilliant timing. Such Masterful scheduling to get that planet discovered Just in the nick of time! with a telescope we built just in the nick of time to see the first transit! Those guys must be rocket scientists!).

If nothing "Fomalhaut-b shattering" happened in the first billion trips through the debris belt, why expect anything THIS time?

Re:25 Ly away (0)

Anonymous Coward | about a year and a half ago | (#42564221)

Why the fuck do people still get modded up for this shit? Maybe I should get modded informative for reminding everyone that 2032 is in 19 years or that a star is a ball of hot gas in space fusing atoms. It's just about as informative.

Its a trap! (4, Funny)

gmuslera (3436) | about a year and a half ago | (#42558961)

Thats no planet.

At least now we know around which star is Alderaan.

Re:Its a trap! (3, Insightful)

Anonymous Coward | about a year and a half ago | (#42559025)

Sorry, Formalhaut is in this galaxy. We have yet to find a similar occurrence in a galaxy far away.

As someone who name his computers after stars of importance in Frontier Elite II I approve of all stories about Formalhaut.

Re:Its a trap! (1)

SuricouRaven (1897204) | about a year and a half ago | (#42559279)

I used to run from there to Sol and back tradeing. I got quite good at docking on manual. Not that I lacked space for a docking computer: I just refused to use something so badly designed that it needed an entire ton of potential cargo capacity to perform a simple docking manouver.

Re:Its a trap! (1)

lxs (131946) | about a year and a half ago | (#42560969)

..and then it still managed to crash into that damn Coriolis station on more than one occasion.
These youngsters don't know how good they have it with their World of Minecraft and their Angry Brides.

Re:Its a trap! (0)

Anonymous Coward | about a year and a half ago | (#42559509)

You know, it's not necessarily the galaxy that's far away. It could just be the events that were far away. The galaxy they happened in could still be ours.

Re:Its a trap! (0)

Anonymous Coward | about a year and a half ago | (#42560619)

Not if proper punctuation is used.
It would have to be "In a galaxy, far, far away" and not "In a galaxy far, far away".

Re:Its a trap! (-1)

Anonymous Coward | about a year and a half ago | (#42559147)

Thats no planet.

At least now we know around which star is Alderaan.

25 LY isn't far. We can send all the niggers, spics, baby boomers, political elite, lardasses, and other undesirables to this planet. Imagine how much better off the rest of us will be. Good riddance!

Re:Its a trap! (4, Funny)

fredrated (639554) | about a year and a half ago | (#42559239)

Have fun when you get there.

Re:Its a trap! (2)

CaptSlaq (1491233) | about a year and a half ago | (#42559241)

Thats no planet.

At least now we know around which star is Alderaan.

25 LY isn't far. We can send all the niggers, spics, baby boomers, political elite, lardasses, and other undesirables to this planet. Imagine how much better off the rest of us will be. Good riddance!

The hitchhikers guide has something to say about that very statement: http://en.wikipedia.org/wiki/List_of_minor_The_Hitchhiker's_Guide_to_the_Galaxy_characters#Telephone_Sanitizer [wikipedia.org]

Re:Its a trap! (0)

drinkypoo (153816) | about a year and a half ago | (#42559569)

25 LY isn't far. We can send all the niggers, spics, baby boomers, political elite, lardasses, and other undesirables to this planet. Imagine how much better off the rest of us will be. Good riddance!

The hitchhikers guide has something to say about that very statement: http://en.wikipedia.org/wiki/List_of_minor_The_Hitchhiker's_Guide_to_the_Galaxy_characters#Telephone_Sanitizer [wikipedia.org]

Why am I suddenly reminded of True Romance?

Re:Its a trap! (1)

Jawnn (445279) | about a year and a half ago | (#42560149)

25 LY isn't far. We can send all the ignorant, racist dumb-fucks, and other undesirables to this planet. Imagine how much better off the rest of us will be. Good riddance!

TFTFY.
Good riddance indeed.

Re:Its a trap! (0)

Anonymous Coward | about a year and a half ago | (#42561281)

25 LY isn't far. We can send all the ignorant, racist dumb-fucks, and other undesirables to this planet. Imagine how much better off the rest of us will be. Good riddance!

TFTFY. Good riddance indeed.

"Baby boomer" is not a race. neither is lardass. thank you for playing but you FAIL. your impotent outrage is entertaining.

Re:Its a trap! (1)

dkleinsc (563838) | about a year and a half ago | (#42559645)

Thats no planet ... that's yo momma!

Life on Earth-like planet (1)

somersault (912633) | about a year and a half ago | (#42558989)

"Maybe there's no land life, but perhaps very clever dolphins," Livio joked.

Except dolphins are descended from land life. Fish are thick as quite thick shit. Most likely due to the lack of sufficient oxygen to run big brains. I hadn't actually considered that before.

Re:Life on Earth-like planet (1)

samkass (174571) | about a year and a half ago | (#42559169)

"Maybe there's no land life, but perhaps very clever dolphins," Livio joked.

Except dolphins are descended from land life. Fish are thick as quite thick shit. Most likely due to the lack of sufficient oxygen to run big brains. I hadn't actually considered that before.

https://en.wikipedia.org/wiki/Cephalopod_intelligence [wikipedia.org]

Re:Life on Earth-like planet (1)

swalve (1980968) | about a year and a half ago | (#42559935)

And squirrels can run up the side of a brick wall. But that don't make them able to do math.

Re:Life on Earth-like planet (2)

wonkey_monkey (2592601) | about a year and a half ago | (#42560687)

Cephalopods know they're not fish.

It's not a moon... (2)

indybob (2731135) | about a year and a half ago | (#42558991)

It's the DEATH STAR!!!

Re:It's not a moon... (1)

guruevi (827432) | about a year and a half ago | (#42559023)

That was what I was thinking. If the thing stops in the next couple of years and turns around, there may be something else going on.

Re:It's not a moon... (2)

CanEHdian (1098955) | about a year and a half ago | (#42559339)

https://petitions.whitehouse.gov/petition/secure-resources-and-funding-and-begin-construction-death-star-2016/wlfKzFkN [whitehouse.gov]

Secure resources and funding, and begin construction of a Death Star by 2016.

Thank you for taking the time to sign this petition. Due to recent leaks in the press, the Death Star project (previously classified [sequentialpictures.com] project names included "Sphere of Phear", "Planet Death", "The Killing Ball", "Death Moon", "Giant Hurt Ball" and "Deathticle" has recently been partially declassified under the IEKINLAS provision.

Your administration has begun work on constructing a Death Star at the Formalhaut Space Dock facilities, and work is [CLASSIFIED]. We expect [CLASSIFIED] to mount an [CLASSIFIED] and when [CLASSIFIED] fully commited, it will be revealed that [CLASSIFIED].

Begs the question... (3, Funny)

Anonymous Coward | about a year and a half ago | (#42559163)

With it's unprecedented ability to plow a path the planetary debris belt without losing suction, it must be a Dyson.... sphere.

It's not a planet (4, Insightful)

Anonymous Coward | about a year and a half ago | (#42559471)

By definition, a planet has cleared its orbit of material. If it's colliding with a belt of debris, it obviously hasn't done so.

Have I mentioned yet how unnatural I think this new definition of a planet is? Its primary purpose seems to be to exclude Pluto and other Kuiper Belt objects from planetary status. Size, mass, and composition are all irrelevant and it's now the orbit of the object (and other objects!) that matter. As this article demonstrates, this new definition conflicts with common understanding of the term. The astronomers should have invented a new term to describe this orbital requirement instead of perverting an existing one.

Re:It's not a planet (2, Insightful)

Anonymous Coward | about a year and a half ago | (#42559775)

By definition, a planet has cleared its orbit of material. If it's colliding with a belt of debris, it obviously hasn't done so.

Have I mentioned yet how unnatural I think this new definition of a planet is? Its primary purpose seems to be to exclude Pluto and other Kuiper Belt objects from planetary status. Size, mass, and composition are all irrelevant and it's now the orbit of the object (and other objects!) that matter. As this article demonstrates, this new definition conflicts with common understanding of the term. The astronomers should have invented a new term to describe this orbital requirement instead of perverting an existing one.

You don't want "planet" to include all the crap that it would have to include in order to be self consistent and include Pluto. And frankly Pluto is obviously the "odd one out" when looking at the "9 planets". It's got by far the most eccentric orbit, is the smallest, and has very little to distinguish it from a big asteroid/comet. The only reason Pluto was considered a planet for so long was that it was discovered early enough that it was not yet apparent how many similar sized objects existed in the various debris fields in the solar system.

Re:It's not a planet (4, Interesting)

wierd_w (1375923) | about a year and a half ago | (#42560339)

*devil's advocate (lame attempt)

Ok, so basically what you are saying is:

"One of these things is not like the others, but rather than actually give due dilligence to a truly thoughtful definition of what a planet is (and thus, what it isn't) that would apply amid the growing dataset of observed orbiting non-stellar objects, we will just pull something out of our asses because we don't want to let pluto into our arbitrarilly segregated "so definately a planet" club, because we don't want to admit such a dinky object, because if we did, then all that rabble would have to be entered too!"

Here's a better definition for planet.

A substellar mass that has achieved a stable, non-random orbit with a stellar mass, and engages in stable harmonic relationships with other orbiting substellar masses.

That would include pluto, due to its harmonic relationship with neptune, and its orderly orbit, even if that orbit is highly eccentric. It also enables objects like extrasolar hot jupiters to be planets, where arbitrary requirements for the shape of the orderly orbit would cause exclusion; many hot jupiters race in toward their parent stars and get roasted regularly due to highly eccentric orbits. Eccentricity is therefor not a quality to cause exclusion, since eccentric orbits are far more prevelent than nearly circular ones. This drives home the point about stable harmonic relationships with other orbiting masses. Crossing eccentric orbits can be harmonically stable.

So, basically, the GP's post about the definition being made specifically to exclude pluto for nebulous and arbitrary reasons is absolutely true, given that eccentrically orbiting extrasolar masses that cross each other's orbits at intervals are abundantly prevelent in the observed galaxy?

Re:It's not a planet (0)

Anonymous Coward | about a year and a half ago | (#42560963)

Your definition of planet would include thousands of already discovered trojan asteroids, a large portion of the outer asteroid belt and trans-Neptune objects. A lot of stuff still in orbit around the sun now is in resonant orbits with other bodies, including things down to the kilometer size. So that definition would expand the number of planets from the classical 9 to tens of thousands, growing thousands each year with new automatic asteroid searches.

As far as trying to exclude Pluto, that wasn't what was on many astronomer's mind. Instead, they were more concerned with trying to exclude Eris and Ceres. If you try to take a quantitative approach at finding parameters that indicate how dominant a body is in its orbit compared to other near by stuff, you'll get Eris, and sometimes Ceres, doing better (i.e. being more of a planet) than Pluto on all of those measures. If you wanted to keep the classical list and only allow newly discovered bodies to be added, then you would have to do a really convoluted definition and dance to make it work, and would get a far more arbitrary definition.

Re:It's not a planet (1)

wierd_w (1375923) | about a year and a half ago | (#42561345)

The list of 9 planets is arbitrary, and retaining it in light of greater discovery is absurd if it can't be rationally justified.

You could instead call it the list of major planets, and have a size cutoff. Then you can keep your precious little list, and still keep a useful definition.

Re:It's not a planet (1)

ceoyoyo (59147) | about a year and a half ago | (#42561739)

That's effectively what they did. Eight major planets, and a whole bunch of minor ones, Pluto being the best known in the latter category.

Re:It's not a planet (1)

wierd_w (1375923) | about a year and a half ago | (#42562629)

Personally, I would offer the following categories:

1) Major planet
2) Minor planet
3) dwarf planet
4) Planetary Object

With other categories for non-planets, like migratory comets, itinerant asteroids, and debris field objects.

A major planet would be large physical volume and or, very high mass objects, like gas giants, very large super-earth type rocky objects (like evaporated gas giant core remnants), and the like. These objects have a criteria for being the major dominant partner within a ratio of the solar system's mass to its volume. EG, Major planets have the majority of the non-solar mass, and dominate large areas of the system.

Minor planets have a minimum weight classification of say, a lunar mass. (Our moon is quite large afterall.) It must have decidedly significant core and crust seperation. Planets like Earth, Venus, and Mars fall into this category.

Dwarf planets are below the mass requirement for minor planet, but still exhibit well defined core/crust segregation. Objects like mercury, Vesta, Ceres, Eris, Pluto and pals live here.

Planetary Objects are massed objects that have "planetary orbital characteristics", but lack any structural stratification. (Asteroids and pals that have reliable, stable, non-erratic orbits.)

The lists of major and minor planets would almost always remain small, while still permitting the "planet" category to be applied to objects with planetary motion characteristics, like irregularly shaped asteroids in well established debris feilds.

It is important that stable orbit be the criterion for defining a planet, because it is essentially the only feature other than mass and degree of occultation we can examine with tools like kepler, and the keck observatory.

Re:It's not a planet (0)

Anonymous Coward | about a year and a half ago | (#42563553)

That is essentially what we have now. Gas giants have their obvious name, and the other large inner planets get called "terrestrial planets" or "rocky planets." Although that distinction is not in the formal definition, it doesn't really need to be as it is pretty consistent in common use in literature. The smaller stuff gets called Small Solar System Body. That all is specific to our solar system, as we don't know the exact boundary between gas giant and terrestrial planets fall in general, and the IAU said they would wait until we have a lot more data before making a decision about where boundaries might be in exoplanets. In general, the category can be referred to as planetary mass objects (PMO), which covers solar system objects, exoplanets, rogue planets, and brown dwarfs, and pretty much is a descriptive name of the property it is based on. There doesn't seem to be enough data about rogue planets or PMOs in unstable orbits to require a class of PMOs excluding them.

Re:It's not a planet (1)

ceoyoyo (59147) | about a year and a half ago | (#42563799)

1. "major planet" = gas giant
2. "minor planet" = terrestrial planet
3. "dwarf planet" = dwarf planet
4. "planetary object" = asteroid, if it's mostly rock, comet if it's mostly ice or moon if it orbits a planet

Except for a few of the names, you pretty much agree with the IAU. The IAU definitions also have the advantage that the features they depend on are related to mass but in many cases easier to see, and don't require arbitrary mass thresholds.

Re:It's not a planet (0)

Anonymous Coward | about a year and a half ago | (#42561747)

A size cutoff was one idea for the formal definition of a planet, but it was considered even more arbitrary/less useful than the definition accepted because there hasn't been much to suggest a functional cutoff in size, as opposed to the current definition that makes some attempt of using a split in the dynamics to make a slightly less arbitrary definition.

Re:It's not a planet (0)

Anonymous Coward | about a year and a half ago | (#42562011)

The main problem is that using the old definitions there was no clear line between a "big asteroid" and a "small planet".

There were many objects that it was agreed upon were "just big asteroids" (primarily because they were objects in the solar systems various debris belts and didn't really distinguish themselves from the other asteroids except by being big enough to be a sphere) but it wasn't practical to not call them planets if Pluto was a planet.

The main culprit IIRC was Eris who's discovery basically started a slippery slope argument, in that there was no way to exclude Eris from "planet" status without also excluding Pluto, and Eris shared so many features with the other "big asteroids" that one Eris was in it would come down to saying "you must weigh as much a Pluto to be a planet". And since no one wanted to include objects like Ceries and Vesta as planets, they had to let Pluto get the ax.

Had they not done that the Majority of planets would have been objects in the various debris belts throughout the solar system.

Re:It's not a planet (0)

Anonymous Coward | about a year and a half ago | (#42562171)

It's got by far the most eccentric orbit, is the smallest, and has very little to distinguish it from a big asteroid/comet.

And yet none of these properties you bring up were used as a distinguishing characteristic for an object to be called a planet. And the point isn't that Pluto should not be distinguished from the other planets, it's that a new term should have been used instead of changing "planet" to this awkward definition.

Another awkward issue with this definition is that Pluto is classified as a "dwarf planet", which any reasonable speaker of the English language would assume implies that Pluto is a type of planet, but, in fact, to astronomers, dwarf planets are not planets. However, these astronomers can't even be internally consistent. To them, a "dwarf star" is a type of star.

Re:It's not a planet (0)

Anonymous Coward | about a year and a half ago | (#42563423)

And yet none of these properties you bring up were used as a distinguishing characteristic for an object to be called a planet.

No, instead they used a different property, the ability of the planet to dominate over other things in its orbit. Several attempts to quantify this show a clear cut between the planets and dwarf planets. Several of the simple examples I've seen show the planets being within a factor of ten of other planets, then a factor of a million jump before you get to Eris and Pluto. Size and eccentricity don't come even close to showing such a clear distinction, with many orders of magnitudes separating them. Heck, such clear cut distinctions are difficult enough to find in other fields, that is on par with the difference between electrical conductors and insulators.

Re:It's not a planet (1)

mark-t (151149) | about a year and a half ago | (#42562611)

The only reason Pluto was considered a planet for so long was that it was discovered early enough that it was not yet apparent how many similar sized objects existed in the various debris fields in the solar system.

Exactly! Just like how we discovered these really tiny particles a couple of centuries back and called them "atoms" because we thought they were indivisible, and when it turned out that they weren't, we.... Oh... Wait a minute, we still *DO* call them atoms.

So... What was I saying?

Re:It's not a planet (0)

Anonymous Coward | about a year and a half ago | (#42563587)

"Light" and "Caloric" used to thought to be indivisible atoms too. They got dropped as the definition improved, or were discovered to be of a different nature.

Re:It's not a planet (1)

NatasRevol (731260) | about a year and a half ago | (#42559983)

Plunk-it?

Re:It's not a planet (0)

Anonymous Coward | about a year and a half ago | (#42560217)

That definition of planet is explicitly for us in our own solar system. The precise definition of an exoplanet has been left to be determined later when we have a better idea of what is out there.

And nothing is stopping you from using your own definition of planet, that other people may or may not agree with (or even may not understand if it is too different). The IAU doesn't have the authority to legally bind people to use their definition. It just created a definition such that when anyone choosing to conform to their definition (e.g. many astronomy journals) refers to "the planets," there is a consistent meaning to the set they are referring to. They can still refer to the planets and dwarf planets, or planets and pluto, if needed. It is the same as when mathematicians stopped counting one as a prime number, they can still to refer to a set of the prime numbers and one, as opposed to if mathematicians decided to keep one as a prime, there would be a crap ton of theorems referring to "the set of prime numbers excluding one." Either way, it is arbitrary, and doesn't have any significant meaning beyond trying to make language consistent and/or convenient.

Re:It's not a planet (1)

Anonymous Coward | about a year and a half ago | (#42562293)

That definition of planet is explicitly for us in our own solar system. The precise definition of an exoplanet has been left to be determined later when we have a better idea of what is out there.

That really is pathetic, and just reinforces my belief that the only purpose of the redefinition of the word "planet" was to exclude Pluto and had no scientific benefit. They should have just invented a new word for an "orbit-clearing-body" and began using that, instead of this fiasco.

Re:It's not a planet (0)

Anonymous Coward | about a year and a half ago | (#42563135)

Because the new discoveries in our own solar system seem to have stabilized into certain patterns, they felt they could make some definition that would clarify new literature on the topic and be stable for some amount of time. The sensitivity and detection methods for exoplanets is still opening up whole new categories of parameters, so they thought they would wait to define that, knowing it could be much more complicated compared to our conveniently simply solar system.

had no scientific benefit.

No jargon definition changes the science, in a direct sense, has no scientific benefit or cost. It is all about making communication clear and consistent, and hopefully convenient for the field. There are a lot of papers that deal with properties of planets and sets of planets. Changing what objects a named set refers to doesn't change any of the science or properties of those objects, only how you describe it.

The funny thing is I remember many astronomers that I worked with, back before the definition being made, being bothered when people kept asking them if Pluto was going to get demoted or not, and their thought was, "What does it matter? Why should we even bother with that issue instead of doing actual science." The once it was done, that just becomes, "What does it matter? Can we just move on now?" Pluto is still the same chunk of rock and ice it was as before, it is just as interesting and important, and we'll still get the same amount of value (or lack of value depending on your perspective) out of exploring now as we would have before. The only thing it changes is it wastes time of astronomers and many potential astronomy fans by arguing over something so insignificant, when the only reason it was really done was to make things more convenient.

Re:It's not a planet (1)

Yoda222 (943886) | about a year and a half ago | (#42566013)

Which fiasco ?

Re:It's not a planet (1)

SecurityTheatre (2427858) | about a year and a half ago | (#42560509)

On consideration, I dislike the definition, although this planet simply cannot have existed very long in its current orbit if it is regularly smashing through a belt of debris. Each transit would wreak havoc on this belt and after a few billion years, it should have been scattered to the wind.

So, either this object was recently (last million years) shifted its orbit has a very unusual orbit, or it is not solid.

The researcher does point out it could be inclined vs the cloud's orbit, which would make it unlikely to interact with the debris, or it could, even, be simply a cloud of ice from a comet smashing event.

As far as the definition of planets, there are two options. Either... every object large enough to maintain hydrostatic equilibrium (i.e. shaped by its own gravity) is a planet, which likely adds 5-8 new planets to our own solar system, or we have to have other criteria, such as a being gravitationally dominant in their orbital region.

Re:It's not a planet (1)

Anonyme Connard (218057) | about a year and a half ago | (#42560743)

By definition, a planet has cleared its orbit of other bodies of similar or larger size other than its own satellites.

With your definition Earth would not be a planet, because there are more than 8000 near-Earth asteroids.

Re:It's not a planet (0)

Anonymous Coward | about a year and a half ago | (#42561689)

By the same definition, a planet orbits the Sun.

So this isn't a planet, anyway.

Re:It's not a planet (1)

ceoyoyo (59147) | about a year and a half ago | (#42561697)

It this thing regularly plows through a ring of protoplanetary material then it is correctly labelled a protoplanet, not a planet. If it has cleared it's orbit, which it may have, and is no longer accumulating lots of material, then it is correctly called a planet.

The definition seems to work very well in this case.

Re:It's not a planet (1)

Relic of the Future (118669) | about a year and a half ago | (#42564515)

...exclude Pluto, other Kuiper Belt Objects, AND asteroids. Remember asteroids? They were "planets" too, for about a century, until there were too many to take seriously. Which is what was going to happen with the KBOs. Pluto had to go, or there had to be over 10,000 "planets." I'd hate to see the mnemonic to memorize them all...

c0m (-1, Flamebait)

Anonymous Coward | about a year and a half ago | (#42559487)

doomsday? (2)

backslashdot (95548) | about a year and a half ago | (#42559533)

I realize the thing is 25 light years away, but surely a large number of people can be tricked into thinking we'll be affected by this somehow. I mean what if there is debris hurtling towards us at near the speed of light the probability of impact is may well be in the one in a googolplexibazillion range but it's still non zero. How many people can understand large numbers? Not many. I say a religion can be formed and money can be made off this.

Re:doomsday? (1)

ehiris (214677) | about a year and a half ago | (#42560107)

The Star is actually the sun's mirror image seen through curved space and the orbiting object is earth.
I read something along those lines on a Mayan wall so it must be true.

Re:doomsday? (0)

Anonymous Coward | about a year and a half ago | (#42560401)

actually it was my space probe that i lost control of. i need better antennas to control these things should of bought Motorola's instead of Chinese knock offs.

Ahem... (1)

koan (80826) | about a year and a half ago | (#42559557)

Deathstar.

Celestial fireworks? (0)

JeanCroix (99825) | about a year and a half ago | (#42559613)

So instead of its usual four pixels, it will be up to, what, six or seven?

Re:Celestial fireworks? (0)

Anonymous Coward | about a year and a half ago | (#42559901)

no, it'll still be four pixels, but they'll be four pixels with a slightly different intensity!

fireworks only if the orbit is in the disk plane (0)

Anonymous Coward | about a year and a half ago | (#42559857)

Anything that makes an object have high eccentricity is likely to push it out of the plane so it won't intersect the disk.

From the second article (0)

Anonymous Coward | about a year and a half ago | (#42559937)

The object takes 242 days to orbit its star (compared to Earth's 365 days)

(emphasis mine)

Whew, glad they told us that!

I'A I'A Cthugha Formalhaut wgah'nagl fhtagn (0)

Anonymous Coward | about a year and a half ago | (#42560065)

Maybe it's not a planet, but a Great Old One? Cthugha is supposed to live there after all...

http://en.wikipedia.org/wiki/Cthugha

Dear Aliens (-1)

Anonymous Coward | about a year and a half ago | (#42560537)

That's what happens when you use Apple Space Maps

Meanwhile, Sometime in the past Near Fomalhaut b.. (2)

sl4shd0rk (755837) | about a year and a half ago | (#42560699)

K'Breel, speaker for the Council, released a statement:

"Gentle Citizens, today I stand before you proud as a gerlsh in the first heivtning, positively quirlly to bring you the news that our collection device near the Eye of Hoarfrost has nearly completed it's mission. Soon, very soon, we will have amassed the largest collection of Dihydrogen Monoxide in Matter state 3 since the dawn of T'zolar. Rest well Citizens knowing this operation marks the age of time we will finally rid Sector 42-Gamma of the evil blue planet"

A media operative, who asked K'breel for comment about several previous attempts, specifically the notorious Jupitorial 9-stone bungle, was tazed in the gelsac and evaporated. The J9S mission, nearly 20 ages old, is apparently still a sore spot with the council.

We keep finding "earth-like" planets... (1)

DeathByLlama (2813725) | about a year and a half ago | (#42562369)

It's great to keep finding these earth-like planets, but wouldn't it make more sense to first focus our searches on:

1) Star systems of the right elemental makeup where planets could have iron cores
2) Star systems of the right age, where the earth-like planets with iron cores would likely still have a molten core capable of producing a magnetosphere

I think we've all but proven that finding planets of the right size, within the right distance of their star, are perhaps abundant enough (see mars). That's great, and we can postulate that there might be liquid water on them because of this, but what we really need to worry about is their ability to produce a magnetosphere capable of holding in all that good stuff against the sweeping winds produced by their star.

Does anyone have some insight as to how easy or hard it would be to try to identify star systems with these characteristics *before* looking to see if we can find earth-like size/distance planets?

that other Earth "like" planet... (1)

Fishbulb (32296) | about a year and a half ago | (#42565353)

FTA:

With a radius that is just 1.5 times that of Earth, the potential planet is what a so-called "super-Earth," meaning it is just slightly larger than the Earth.

Assuming it has a similar density to Earth, wouldn't it have considerably more gravitational force? Like, maybe 3x?

Earth's volume: 4/3 * pi * r^3 = 4/3 * 3.14159 * 1^3 = 4.1888
KOI 172.02's volume: 4/3 * 3.14159 * 1.5^3 = 14.137

People seem to forget that a small difference in radius produces a much larger difference in volume thanks to that r-cubed thing. "Slightly larger" equates to "much more massive" (given same density).
Or am I way off here?

Re:that other Earth "like" planet... (1)

Anonyme Connard (218057) | about a year and a half ago | (#42566461)

Volume, hence mass if density is similar, hence gravity, is proportional with the cube of the radius. But gravity is also proportional with the inverse square of the distance from the center. Therefore gravity on a planet surface is proportional with its radius: R^3/R^2 = R.

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