/sci/ - Science & Math

It soooorta is.
It's just a really really big gas planet that is undergoing fusion.

at what point does an astronomical body become large or small enough to be classified as a planet and not a moon or an asteroid or whatever?

>>1516559
You're retarded.

The sun is a planet in the same way that a black hole is a planet - it's a mass of matter and energy floating in the universe. Which is to say it's not a planet at all.

There are classifications for these things, and the sun -isn't- a planet. Had she said "celestial body" that would have been hokey but factual.

How it affects or does not affect us is up for debate, though I do not doubt the massive amounts of particles and radiation the sun spits out interfere somewhat with our lives.

>>1516559
The definition of a planet is a body with the gravity to make itself a sphere THAT ORBITS A STAR.

Well there is not definite definition yet, only rough ones, that's why there is the fuss with Pluto.

>>1516583

I'm no physicist but aren't planets large bodies that orbit a star? How can a star orbit itself?

>>1516595
Some stars orbit other stars.

>>1516597
And that's called a binary STAR.

She's right, though. Planet comes from planes, "wanderer", and was used to refer to objects that moved relative to the background of fixed stars. The sun and the comets were traditionally called planets.

Yes, the modern definition is different, but if you start condemning traditional usages of the term it won't be long before you're calling Obama a Socialist and taking offence to the Founding Fathers being classified as liberals.

>>1516594

(1) A planet is a celestial body that (a) is by far the largest object in its local population[1], (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape [2], (c) does not produce energy by any nuclear fusion mechanism [3].

(2) According to point (1) the eight classical planets discovered before 1900, which move in nearly circular orbits close to the ecliptic plane are the only planets of our Solar System. All the other objects in orbit around the Sun are smaller than Mercury. We recognize that there are objects that fulfill the criteria (b) and (c) but not criterion (a). Those objects are defined as "dwarf" planets. Ceres as well as Pluto and several other large Trans-Neptunian objects belong to this category. In contrast to the planets, these objects typically have highly inclined orbits and/or large eccentricities.

(3) All the other natural objects orbiting the Sun that do not fulfill any of the previous criteria shall be referred to collectively as "Small Solar System Bodies".[4]

Definitions and clarifications

1. The local population is the collection of objects that cross or closely approach the orbit of the body in consideration.
2. This generally applies to objects with sizes above several hundred kilometers, depending on the material strength.
3. This criterion allows the distinction between gas giant planets and brown dwarfs or stars.
4. This class currently includes most of the Solar System asteroids, Near-Earth objects (NEOs), Mars-, Jupiter- and Neptune-Trojan asteroids, most Centaurs, most Trans-Neptunian Objects (TNOs), and comets.[23]
Note: There is still some controversy, but this is more complete.

>>1516598
So how do they decide which one is the planet then?

>>1516594

Pluto is a planet as are the ones further out too, the only reason it is not classed as one at the moment is that a bunch of piss poor scientists decided 'no fuck science, I liked it better when there was a known and certain number of planets in the solar system like when I was a kid, if we have to sacrifice Pluto's planetary status and call it another name just so I can be unscientific so be it'.

>>1516605
They're both stars.

>>1516605
None of them are planets. the problem is that this "aren't planets large bodies that orbit a star?" is false. And the IAU definition I copied in the other post only applies to or Solar System. There is no official definition for extrasolar systems yet, even when astronomers talk about extrasolar planets.

>>1516607
0/10

>>1516620
oops:
"only applies to or Solar System" must say "only applies to our Solar System"

>>1516589
I know a star is a star. I'm saying the only real difference is that it's undergoing fusion and usually orbits the galaxy.

What makes a planet a planet is that it orbits a star, not a black hole.

Binary stars are binary stars, they can't even have planets.

>>1516628
By definition, planets also orbit the galaxy.

>>1516638
There are extrasolar planets in binary systems, and even planets around pulsars (although these are thought to have formed from the supernova remnant).

>>1516622

Not a troll.

Bodies like Pluto and those further out are planets in all but name and to call them anything else just based on placing any arbitary cut off point on distance from the sun, orbit or diameter makes a complete mockery of the whole system. An asteroid or a comet is not a planet even if it is very large but a planet is a completely different thing calling them something else for convenience sake is unscientific and it is embarrassing that this was allowed to happen. Soon the new rules of nomculture will probably be revised again. The current system is a fudge.

>>1516607

Pluto and the other objects like it are called dwarf planets.

The term is defined by the IAU as following

>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) shape2, (c) has not cleared the neighbourhood around its orbit, and (d) is not a satellite.

>>1516677

I agree, it is bad science.

>>1516706

What's in a name? That which we call a rose by any other name would smell just as sweet.

>>1516716
Poetry? In my /sci/?

>>1516677
Note how you have provided nothing else apart from a sentimental argument.
Also,
>>1516677
>>1516706
probably samefag.

>>1516734

>Note how you have provided nothing else apart from a sentimental argument.

Not really. There is nothing sentimental about saying that science and the expansion of knowledge should take priority over someone saying "ooh those are awfully big numbers, my head hurts, I know lets cook the books to ensure that there is a definite number of planets in the solar system.".

Choosing an arbitrary cut off point based on the fact that it will conveniently exclude all planets discovered after say 1900 like 'anything smaller than Mercury isn't a planet' is ludicrous and the sort of thing an accountant would do rather than a real scientist.

Imagine if such logic were applied to other things in science:

-Any species around before the quaternary must now be called a 'hugaboo' because it is like really really old so can't be a proper species like we have today.

-Electricity at over 1.5 volts ceases to be known as electricity and must be called Kevin because my uncle is called Kevin.

-All speeds over the speed of sound are now known as zoomyness because it is really fast.

See? It's all a bit stupid, childish and unscientific doing things like that.

>>1516897

Your analogies hold no water

>>1516897
Bodies in the Kuiper Belt clearly are a different class of objects as compared to the 8 planets.
Using your arguments, we should call anything orbiting the Sun a planet.
Also, your comparisons do not make sense because they are systems with very different properties.
Finally, there is nothing inherently wrong with creating classifications systems as long as they are consistent. I agree the current IAU system has some deficiencies, but Pluto being left out as a planet does make a sense in terms of populations.

>>1516897
To understand better what's going on, you should read something about this:

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

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

>>1516589
Skin cancer

>>1516897
Classifying things based on size/shape/etc is perfectly good science, and a good thing to do, especially if you have a fuckload of stuff out in space with different properties.
Also, no one gives a fuck about what is and isn't a planet, it's just a convenient term so people know roughly what you're talking about, saying "look at this planet" is a completely empty statement, what you want to know is:
What is the composition?
What is the distance to it's star?
Does it have liquid water?
etc

The dwarf planet Eris caused the current debate. there are many objects in the solar system the size of pluto. Some even have closer orbits to the sun.

>>1516967

Any kuiper belt planet should be called a planet regardless of size. An asteroid or comet are different things again and do account for many of the kuiper belt objects.

As to the comparisons I provided being systems with very different properties, had you read the post rather than just skimmed it you would have seen that that was king of the point. I was pointing out the folly of setting up arbitrary, unnecessary classifications which just fudge the issue and how this would look if applied to other things in science.

It is all well and good to have a classification system but when that system has been compromised and messed around with so it no longer fits what is actually there and just serves to protect an outdated concept like there being a set number of planets in the solar system and anything added to that since Victorian times isn't a real planet the system is a laughing stock based not on science but man's prejudices.

How would this system be applied to star systems other than our own? Not only is it arbitrary but it may cause more problems further down the line.

A question for any astronomers/ astro-physicists/ astrologers out there:

George was a perfectly good name for a planet, it was only the French that started calling it Uranus (typical).

Why didn't they rename Uranus George, as it was originally named when they had the conference to decide on what was a planet or not?

>your face when you realized that fat women are never smart

>>1517218
astrologers need to gtfo of my /sci/ unless they come to sincerely apologize

>>1517199
It's sad to see how you don't notice the immense difference of the things you are comparing a planetary system to.

> but when that system has been compromised and messed around with
You seem to be unaware of history of science.

> so it no longer fits what is actually there
This makes complete nonsense! Learn what is what science does.

> and just serves to protect an outdated concept like there being a set number of planets in the solar system

That's not the point. You are missing the real reasons for the classifications. Your arguments still can be used to defend the classification of anything orbiting the Sun as planets, including asteroids and comets. Do yourself a favor and read more about our Solar System.
You can use this book in the image, for example.

Moreover, since your argument is that we shouldn't mess around with things anymore, and you claim that changing arbitrarily the limits of numbers is the issue, what makes you think that we had enough changes?
Then you are limiting the number of times we are fiddling with these concepts arbitrarily, imposing an artificial number.

>>1516716
taxonomy disagrees.

>>1517199
Regarding other planetary systems, it happens that we only have rich details of our own (even considering we still have a lot to learn!), so this definition only applies to ours. There are already some problems, like the so-called 'free floating planets' and even a possible 'double planet'. This only shows that we need to reconsider things and mess with our classification systems, in the same way that zoology had to create classifications to make sense of the living species.
It happens that not all the bodies in our Solar System have the same origin nor formation time scales, dynamics, composition, etc. That's why classification is important. It plays a role as important as that of cladistics to understand evolution.
Again, limiting the number of changes we can make just because "it's been too many times" actually goes against scientific progress.
If at this point you still don't understand the point, you need to go deeper into books.

>>1517227

>implying that the study of how the universe effects the lives of every single person on Earth, that has been studied objectively for millennia is in some way not science.