Is Pluto a planet?

Stacey.

Yeah I think it's a planet.

Turtwig

Sink The Banana wrote: »

This is language they speak on pluto???

It's remarkably comprehensible.

FreudianSlippers

FreudianSlippers wrote: »

Is it a dwarf planet or a planetesimal? Either way, it's not a planet - if it were then we'd have to make larger planetesimals in the Kuiper belt planets.

Answered my own question

The term "planetesimal" refers to small bodies that orbited the Sun prior to the planets' formation. In 2006, the International Astronomical Union (IAU) ruled that a "dwarf planet" is a nearly spherical celestial body orbiting the Sun that has not cleared its orbital path of debris, as have the traditional planets.

In any event, Pluto is most certainly not a planet.

calabi yau

oneillMan999 wrote: »

Yes its a planet, just cause a few astronomers decided they didnt want it to be a planet dosent mean its not, Pluto is a planet in the solar system and always will be.

No, this is not the case. It does not behave like the other planets. Please watch DeGrasse Tyson, the man partly responsible for downgrading it, on the subject. He has convinced me. Just because you have an affinity towards it, does not "make it so"

slade_x

oneillMan999 wrote: »

Yes its a planet, just cause a few astronomers decided they didnt want it to be a planet dosent mean its not, Pluto is a planet in the solar system and always will be.

Its not about not wanting it to be a planet its about appropriate categorisation. Pluto hasnt left the solar system as a result, it is still very much a member, now it belongs in a more appropriate category of objects which will grow exponentially in the next few years as more and more objects like it will be isolated/ found

And i wouldnt consider The International Astronomical Union with over 10,000 members just a few astronomers. Classification of such objects and standards are not for the general public to decide. IAU is not a bunch of amateur astronomers it is an organisation of Professionals. Membership requires a Ph.d at the very least.

Rubecula

Pluto is quite reflective. i.e it is white. It is also small. i.e. a dwarf.

I hereby declare that from now on Pluto is really a White Dwarf.:D:D:D

Seriously, just because we we taught in school that Pluto was a planet does not make it so. I was also taught that there is a planet X that is out there and astronomers were looking for it. It is not there as far as we know, and wishing it was does not make it so.

As much as we may dislike the idea, it is something we just have to live with. Pluto is still there and still the same as it was, so who cares what it is called really, it won't affect Pluto, which does not care one iota what we call it.

Turtwig

Edwin Schrodinger wrote:

Unfortunately, school teaching keeps up certain traditional views, which have been out of date for many years and which obscure the understanding of the actual state of affairs.

Love Edwin.:D

osnola ibax

Rubecula wrote: »

Pluto is quite reflective. i.e it is white. It is also small. i.e. a dwarf.

I hereby declare that from now on Pluto is really a White Dwarf.:D:D:D

Seriously, just because we we taught in school that Pluto was a planet does not make it so. I was also taught that there is a planet X that is out there and astronomers were looking for it. It is not there as far as we know, and wishing it was does not make it so.

As much as we may dislike the idea, it is something we just have to live with. Pluto is still there and still the same as it was, so who cares what it is called really, it won't affect Pluto, which does not care one iota what we call it.

I remember hearing about a tenth planet "Smily" from my physics teacher.

clintondaly

so this isnt a thread on loved Disney characters

Batsy

Up until 2006, there were deemed to be nine planets in the Solar System.

Now there are only eight.

In the late 20th and early 21st century, many objects similar to Pluto were discovered in the outer Solar System, notably the scattered disc object Eris in 2005, which is 27% more massive than Pluto. On August 24, 2006, the International Astronomical Union (IAU) defined what it means to be a "planet" within the Solar System. This definition excluded Pluto as a planet and added it as a member of the new category "dwarf planet" along with Eris and Ceres. After the reclassification, Pluto was added to the list of minor planets and given the number 134340.

Pluto has four known moons, two of them being discovered as recently as 2005 (Nix and Hydra) and one (provisionally named S/2011 P 1) discovered on 20th July 2011.

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

Zubeneschamali

Batsy wrote: »

Up until 2006, there were deemed to be nine planets in the Solar System. Now there are only eight.

This is the short version, which rather encourages the "Pluto is so a planet!" brigade.

In fact, there used to be 5 planets: Mercury, Venus, Mars, Jupiter and Saturn. Then Copernicus, Kepler and friends decided Earth was a planet, too. Then Uranus was discovered, so there were 7. Then Ceres, Pallas, Juno and Vesta were discovered, and there were 11 planets for more than 30 years. Then Neptune and a load more asteroids were discovered, so one planet was added and 4 demoted and we had 8. Then Pluto was discovered, and we had 9. Finally pluto was demoted for the same reason the Asteroids were, the discovery of a whole class of similar small objects.

In the longer version, it's clear that Pluto wasn't suddenly picked from the "real" list of 9 and demoted, this kind of reclassification has been going on since the 16th century.

Cú Giobach

Terrestrial Planet = Planet
Gas Giant Planet = Planet
Ice Giant Planet = Planet
Dwarf Planet ≠ Planet

RichieC

Zubeneschamali wrote: »

In the longer version, it's clear that Pluto wasn't suddenly picked from the "real" list of 9 and demoted, this kind of reclassification has been going on since the 16th century.

Yea but this is different since it's the only planet discovered by America. which is the only reason this got the air time it did.

oneillMan999

slade_x wrote: »

Its not about not wanting it to be a planet its about appropriate categorisation. Pluto hasnt left the solar system as a result, it is still very much a member, now it belongs in a more appropriate category of objects which will grow exponentially in the next few years as more and more objects like it will be isolated/ found

And i wouldnt consider The International Astronomical Union with over 10,000 members just a few astronomers. Classification of such objects and standards are not for the general public to decide. IAU is not a bunch of amateur astronomers it is an organisation of Professionals. Membership requires a Ph.d at the very least.

Interesting...








Its still a planet though..

Agent Smith

Turtwig

Why address NASA? ? ?

RichieC

Because space belongs to america!

shizz

looks more like Venus as well

Turtwig

shizz wrote: »

looks more like Venus as well

Ehh? ? ?



Edit : I'll have me humble pie, just realised what you meant.

Cú Giobach

shizz wrote: »

looks more like Venus as well

I think it looks more like a Mars/Io cross, and a "halfbreed" of a moon and a planet campaigning for the reinstatement of Pluto seems quite logical*.



*Could be an illogical use of the word logic.

Ellis Dee

No, Pluto is a dog. Well, actually not a dog. A cartoon representation of a dog.

gkell1

Zubeneschamali wrote: »

This is the short version, which rather encourages the "Pluto is so a planet!" brigade.

In fact, there used to be 5 planets: Mercury, Venus, Mars, Jupiter and Saturn. Then Copernicus, Kepler and friends decided Earth was a planet, too. Then Uranus was discovered, so there were

The word 'planet' as distinct from the moon,Sun and other stars has a specific meaning which relates to its observed motion and nowhere did the astronomers from antiquity and up to the time of Copernicus ever doubt that the Earth was a planet just like the other 5 observed planets -

"Moreover, we see the other five planets also retrograde at times, and stationary at either end [of the regression]. And whereas the sun always advances along its own direct path, they wander in various ways, straying sometimes to the south and sometimes to the north; that is why they are called "planets" [wanderers]. " Copernicus ,De Revolutionibus

He refers to the illusion that planets sometimes stop,go backwards and then move forwards periodically which is due to the motion of our planet as it orbits the Sun along with the other 8 planets -

http://apod.nasa.gov/apod/ap011220.html

A reasonable person looks at the matter and decides that people today are not trying to define a planet or consider whether Pluto is a planet or not,they are attempting to demote the meaning of planet from its original sense as astronomers understand these things,hence it is more like dumbing down the interpretation of what a planet is rather than clarifying it.

The real issue is how one man got it badly wrong in the late 17th century and why people today,even with the benefit of imaging and time lapse footage continue to support his idiotic notion which disrupts the view of what retrogrades actually are,again, an illusion seen from a moving Earth,nothing more and nothing less -

"For to the earth planetary motions appear sometimes direct, sometimes stationary, nay, and sometimes retrograde. But from the sun they are always seen direct" Newton

The reason why the planet 'definition' arose in the first place is due to the lack of appreciation of what Copernicus actually did and how he did it.

Cú Giobach

gkell1

There is no difficulty forming a picture of planetary dynamics or solar system structure in this era where the ability to present relevant images is almost immediate and while it would normally be of secondary importance to remove unwanted and unhelpful perspectives,when conceptions that link astronomical cause to terrestrial effects are an issue and a where a false perspective is dominant,it is necessary to tackle the technical details at their roots.

The fact is that retrogrades are an illusion hence there is no need to appeal to any other solution than the one where we see the motions of the other planets from a moving Earth -

http://www.paulineedward.com/retro_tech.html

http://apod.nasa.gov/apod/ap031216.html

The dominant empirical view is unhelpful as well as being invalid even if it fits into an expanded agenda that now has painted itself into a conceptual corner -

"For to the earth planetary motions appear sometimes direct, sometimes stationary, nay, and sometimes retrograde. But from the sun they are always seen direct" Isaac Newton

Over the years it has become customary to turn the technical details surrounding retrogrades into an excuse for personal confrontation but the genuine astronomer would only see the topic as a means to extract perceptual mutations introduced by the empirical view from the genuine way retrogrades were viewed and resolved by Copernicus and understood by astronomers such as Galileo and Kepler.In short,if the APOD images are not good enough to expose a problem caused a few centuries ago then nothing will.

A person who truly understands that the name 'planet' is linked to apparent retrogrades would not try to define a planet in terms of size or composition no more than they would need to distinguish people of different sizes,gender or color.

FreudianSlippers

Copernicus also thought that the Sun was the centre of the universe and that the planets did not move, only the earth - so while his definition of a planet was useful in forming the modern definition; it's most certainly not the most correct definition.

gbee

FreudianSlippers wrote: »

Copernicus also thought

My understanding is that Nicolaus Copernicus correctly identified the order of the solar system but faced excommunication, imprisonment and possibly even death for hearsay.

FreudianSlippers

gbee wrote: »

My understanding is that Nicolaus Copernicus correctly identified the order of the solar system but faced excommunication, imprisonment and possibly even death for hearsay.

Galileo was convicted of heresy for publicly accepting Copernicus's theory; Copernicus actually didn't publish his theory until right before he died, so he wasn't excommunicated.

I looked it up and I was actually wrong about one aspect; Copernicus did believe that all of the planets orbited the Sun.

gkell1

FreudianSlippers wrote: »

Copernicus also thought that the Sun was the centre of the universe and that the planets did not move, only the earth - so while his definition of a planet was useful in forming the modern definition; it's most certainly not the most correct definition.

How many readers would know that 2012 will be the 500th anniversary of the arguments for the daily and orbital motions of our planet using the motion of the other planets and ours to explain the orbital motion of the Earth leaving daily rotation to explain the return of the Sun each day.Copernicus wrote the outlines of his arguments about 30 years before 'De Revolutionibus ' appeared and his simple sketch can be read by anyone with curiosity and intelligence to pick up on how he went about things -

http://dbanach.com/copernicus-commentarilous.htm

Assumptions 6 and 7 in that small treatise are still dramatic and would have been to his contemporaries who had been brought up with the idea of a stationary Earth and particularly the 'wandering' feature of other planets which sets a planet apart from the moon and the Sun -

http://apod.nasa.gov/apod/ap031216.html

gkell1

gbee wrote: »

My understanding is that Nicolaus Copernicus correctly identified the order of the solar system but faced excommunication, imprisonment and possibly even death for hearsay.

The technical and historical details are nothing like the fiction most here receive,mostly to make the people in the late 17th century look good.Galileo had a fair grasp of the history of the development of the Earth's planetary dynamics and it just goes to show how things can be manipulated to suit a dominant agenda,in this era it is Royal Society empiricism.

"In order to facilitate their designs, they seek so far as possible (at least among the common people) to make this opinion seem new and to belong to me alone. They pretend not to know that its author, or rather its restorer and confirmer, was Nicholas Copernicus; and that he was not only a Catholic, but a priest and a canon. He was in fact so esteemed by the church that when the Lateran Council under Leo X took up the correction of the church calendar, Copernicus was called to Rome from the most remote parts of Germany to undertake its reform.The Bishop of Culm, then superintendent of this matter, assigned Copernicus to seek more light and greater certainty concerning the celestial motions by means of constant study and labor. With Herculean toil he set his admirable mind to this task, and he made such great progress in this science and brought our knowledge of the heavenly motions to such precision that he became celebrated as an astronomer. Since that time not only has the calendar been regulated by his teachings, but tables of all the motions of the planets have been calculated as well. Having reduced his system into six books, he published these at the insistence of the Cardinal of Capua and the Bishop of Culm. And since he had assumed his laborious enterprise by order of the supreme pontiff, he dedicated this book On the celestial revolutions to Pope Paul III. When printed, the book was accepted by the holy Church, and it has been read and studied by everyone without the faintest hint of any objection ever being conceived against its doctrines." Galileo

In short,the convenient story of Church opposition starts to break down but to work through the fascinating history which can be bookended between the emergence of the arguments for the Earth's motions in the early 16th century and their disappearance in the late 17th through the efforts of Royal Society empiricism.

Turtwig

gkell1 wrote: »

The reason why the planet 'definition' arose in the first place is due to the lack of appreciation of what Copernicus actually did and how he did it.

Copernicus assumed all the planets had a circular orbit. That assumption was why no one would ever accept what he did. When it cames to predicting a body's location Ptolemy's modified model was so useful; Copernicus' almost useless.