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Exoplanets also aren't planets. Some things just seem to have definitions with a history that get applied to new discoveries that don't fall within the definiti

by Aachen 4mo ago

Exoplanets also aren't planets. Some things just seem to have definitions with a history that get applied to new discoveries that don't fall within the definition. Distinguishing random rocks in space from planets was done by requiring planets to orbit around the sun, and so planets elsewhere cannot be called planets no matter that it's 1:1 the same thing. Biology probably has a similar history of trying to draw a line somewhere between what was created and what evolved to be part of the 'natural' world

oliverx0 4mo ago
Exoplanets are planets. Also, for clarification, biology is not defined as “the study of things produced exclusively by natural evolution.” Synthetic biology works with biological components and living systems (DNA, proteins, regulatory networks, cells and organisms). It differs from much traditional biology mainly in its constructive, engineering-oriented approach. Synthetic systems are often built precisely to test hypotheses about how natural biological systems function. Claiming it is not biology is wrong IMO.
- ferfumarma 4mo ago
  Right? It's biology when you study enzymes in vitro, but as soon as you put a membrane around them then it's ... something else? Bizarre argument.
- cookingmyserver 4mo ago
  For anyone else that might be curios, the definition of a planet you will often see quoted online applies to bodies in our Solar System. It comes from the International Astronomical Union in 2006. This is the famous definition that dropped Pluto as a planet. While the criteria are widely quoted, that actual resolution isn't. The resolution: The IAU...resolves that planets and other bodies, except satellites, in the Solar System be defined into three distinct categories in the following way: (1) A planet [1] is a celestial body that (a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, and (c) has cleared the neighbourhood around its orbit. (2) A "dwarf planet" is a celestial body that (a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape [2], (c) has not cleared the neighbourhood around its orbit, and (d) is not a satellite. (3) All other objects [3], except satellites, orbiting the Sun shall be referred to collectively as "Small Solar System Bodies". The definition here only applies to bodies in the Solar System. Still a bad definition IMO. According to the definition if a catastrophic event were to occur that cluttered the neighborhood of a planet it would cease to be a planet until it was cleaned up. The definition of a planet should be based in the physical attributes of the celestial body itself, not in its role or relationship with other bodies. I'm a bit of an extremist on this front. Even our Moon would be a planet in my opinion. Seems silly when you think about our barren moon but there are for sure habitable moons out there. I can't imagine asking an alien "What planet are you from?" and them responding "erm, actually we are from a moon/planetary satellite".
  - hparadiz 4mo ago
    > Captain's Log, Stardate 1513.1. Our position, orbiting planet M-113. On board the Enterprise, Mr. Spock, temporarily in command. <<insert nerd screeching about the word planet>>
  - paulddraper 4mo ago
    Eh, that doesn't make sense. What's a meteor?
    - cookingmyserver 4mo ago
      The streak of light generated by a small astronomical body as it moves through the atmosphere of earth (or another astronomical body).
      - paulddraper 4mo ago
        Meteoroid then. Asteroids and meteoroids are the same, except for where they are positions. Mothers and women are the same, except for their relationships to others.
        cookingmyserver 4mo ago
        And notice how we have those two different words - mother and woman? You can have words that describe relationships, in fact that is really good! You can even compound words or create whole new ones to encompass multiple types of attributes! What we should avoid is taking widely used words and changing the definition to add a criterion that is of a whole other type of attribute. Your mother and woman example is perfect! It would not be appropriate to most people to change the definition of woman to a female that had or has an offspring. You are taking a definition that describes an attribute of the subject (gender) and throwing in criteria that is based on a relationship. That makes no sense! If it is important for you to make a distinction on whether an astronomical body has cleared its neighborhood then you can create a new word or compound word.
hparadiz 4mo ago
> Exoplanets also aren't planets. Imagine writing this.
- Aerolfos 4mo ago
  Actually, that is the IAU stance. And their definition for exoplanet includes small, non-rounded objects orbiting stars which would be asteroids (or comets or whatever) if they happened to be around the Sun. All that debacle around dwarf planets to prepare for future observations, and yet the distinction ceases to apply the moment you go outside the Oort cloud... But really, that's just the naming systems being bad, obviously common people don't think asteroids around other stars are "exoplanets" or should be called that way
  - hparadiz 4mo ago
    I'm not talking about edge cases like asteroids or planetoids or dwarf planets. I'm talking about actual planets. Like a gas giant orbiting a star. It's obviously a planet even if it's not orbiting Sol.
    - ben_w 4mo ago
      It's perfectly coherent to argue that gas giants should count failed stars rather than as planets, given the boundary between them is under debate. https://en.wikipedia.org/wiki/WISE_0855%E2%88%920714 https://en.wikipedia.org/wiki/WISE_0855%E2%88%920714
      - jibal 4mo ago
        It's perfectly irrelevant to the thread.
        ben_w 4mo ago
        This thread is ~ "Exoplanets also aren't planets": discuss As the easiest to discover exoplanets (and all the early ones except pulsar planets) are gas giants, and the comment I was directly replying to had "Like a gas giant orbiting a star. It's obviously a planet", therefore "gas giants are failed stars and shouldn't count as planets" is not at all irrelevant. Even further up to the point of if these are or are not cell, it illustrates how taxonomical categories are made by humans for humans. Historically, any connection to natural laws in taxonomies is often mere coincidence.
jibal 4mo ago
> Exoplanets also aren't planets. That is flatly wrong. https://en.wikipedia.org/wiki/Exoplanet https://en.wikipedia.org/wiki/Exoplanet "An exoplanet or extrasolar planet is a planet outside the Solar System."
- MarkusQ 4mo ago
  The GP post's point was that, logical as this would be, the IAU definition explicitly states that planets are "in the Solar System". So no, exoplanets are exoplanets, not planets. And Pluto isn't an example of either.
  - jibal 4mo ago
    No, The IAU definition does not say that. You and others are confusing the definition of a planet with its application to planets in the solar system (and thus to Pluto) -- IAU Resolution 5A: Definition of a Planet in the Solar System. The IAU of course does not assert that only planets in the solar system are planets ... that would be ridiculous, and the interpretation of the IAU's stance as being so ridiculous is ridiculous and then some. https://science.nasa.gov/solar-system/planets/what-is-a-planet/ https://science.nasa.gov/solar-system/planets/what-is-a-plan... "The definition of a planet adopted by the IAU says a planet must do three things: It must orbit a star (in our cosmic neighborhood, the Sun). It must be big enough to have enough gravity to force it into a spherical shape. It must be big enough that its gravity has cleared away any other objects of a similar size near its orbit around the Sun." https://www.iau.org/IAU/Science/What-we-do/Pluto-and-the-Developing-Landscape-of-Our-Solar-System.aspx https://www.iau.org/IAU/Science/What-we-do/Pluto-and-the-Dev... "More generally, a planet: a. orbits its host star, just as the Earth and Jupiter orbit the Sun, b. is large enough to be mostly round, and c. must have an important influence on the orbital stability of the other objects in its neighbourhood."

by Aachen 4mo ago

oliverx0 4mo ago

Exoplanets are planets. Also, for clarification, biology is not defined as “the study of things produced exclusively by natural evolution.” Synthetic biology works with biological components and living systems (DNA, proteins, regulatory networks, cells and organisms). It differs from much traditional biology mainly in its constructive, engineering-oriented approach. Synthetic systems are often built precisely to test hypotheses about how natural biological systems function. Claiming it is not biology is wrong IMO.

ferfumarma 4mo ago
Right? It's biology when you study enzymes in vitro, but as soon as you put a membrane around them then it's ... something else? Bizarre argument.
cookingmyserver 4mo ago
For anyone else that might be curios, the definition of a planet you will often see quoted online applies to bodies in our Solar System. It comes from the International Astronomical Union in 2006. This is the famous definition that dropped Pluto as a planet. While the criteria are widely quoted, that actual resolution isn't. The resolution: The IAU...resolves that planets and other bodies, except satellites, in the Solar System be defined into three distinct categories in the following way: (1) A planet [1] is a celestial body that (a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, and (c) has cleared the neighbourhood around its orbit. (2) A "dwarf planet" is a celestial body that (a) is in orbit around the Sun, (b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape [2], (c) has not cleared the neighbourhood around its orbit, and (d) is not a satellite. (3) All other objects [3], except satellites, orbiting the Sun shall be referred to collectively as "Small Solar System Bodies". The definition here only applies to bodies in the Solar System. Still a bad definition IMO. According to the definition if a catastrophic event were to occur that cluttered the neighborhood of a planet it would cease to be a planet until it was cleaned up. The definition of a planet should be based in the physical attributes of the celestial body itself, not in its role or relationship with other bodies. I'm a bit of an extremist on this front. Even our Moon would be a planet in my opinion. Seems silly when you think about our barren moon but there are for sure habitable moons out there. I can't imagine asking an alien "What planet are you from?" and them responding "erm, actually we are from a moon/planetary satellite".
- hparadiz 4mo ago
  > Captain's Log, Stardate 1513.1. Our position, orbiting planet M-113. On board the Enterprise, Mr. Spock, temporarily in command. <<insert nerd screeching about the word planet>>
- paulddraper 4mo ago
  Eh, that doesn't make sense. What's a meteor?
  - cookingmyserver 4mo ago
    The streak of light generated by a small astronomical body as it moves through the atmosphere of earth (or another astronomical body).
    - paulddraper 4mo ago
      Meteoroid then. Asteroids and meteoroids are the same, except for where they are positions. Mothers and women are the same, except for their relationships to others.
      - cookingmyserver 4mo ago
        And notice how we have those two different words - mother and woman? You can have words that describe relationships, in fact that is really good! You can even compound words or create whole new ones to encompass multiple types of attributes! What we should avoid is taking widely used words and changing the definition to add a criterion that is of a whole other type of attribute. Your mother and woman example is perfect! It would not be appropriate to most people to change the definition of woman to a female that had or has an offspring. You are taking a definition that describes an attribute of the subject (gender) and throwing in criteria that is based on a relationship. That makes no sense! If it is important for you to make a distinction on whether an astronomical body has cleared its neighborhood then you can create a new word or compound word.

hparadiz 4mo ago

> Exoplanets also aren't planets. Imagine writing this.

Aerolfos 4mo ago
Actually, that is the IAU stance. And their definition for exoplanet includes small, non-rounded objects orbiting stars which would be asteroids (or comets or whatever) if they happened to be around the Sun. All that debacle around dwarf planets to prepare for future observations, and yet the distinction ceases to apply the moment you go outside the Oort cloud... But really, that's just the naming systems being bad, obviously common people don't think asteroids around other stars are "exoplanets" or should be called that way
- hparadiz 4mo ago
  I'm not talking about edge cases like asteroids or planetoids or dwarf planets. I'm talking about actual planets. Like a gas giant orbiting a star. It's obviously a planet even if it's not orbiting Sol.
  - ben_w 4mo ago
    It's perfectly coherent to argue that gas giants should count failed stars rather than as planets, given the boundary between them is under debate. https://en.wikipedia.org/wiki/WISE_0855%E2%88%920714 https://en.wikipedia.org/wiki/WISE_0855%E2%88%920714
    - jibal 4mo ago
      It's perfectly irrelevant to the thread.
      - ben_w 4mo ago
        This thread is ~ "Exoplanets also aren't planets": discuss As the easiest to discover exoplanets (and all the early ones except pulsar planets) are gas giants, and the comment I was directly replying to had "Like a gas giant orbiting a star. It's obviously a planet", therefore "gas giants are failed stars and shouldn't count as planets" is not at all irrelevant. Even further up to the point of if these are or are not cell, it illustrates how taxonomical categories are made by humans for humans. Historically, any connection to natural laws in taxonomies is often mere coincidence.

jibal 4mo ago

> Exoplanets also aren't planets. That is flatly wrong. https://en.wikipedia.org/wiki/Exoplanet https://en.wikipedia.org/wiki/Exoplanet "An exoplanet or extrasolar planet is a planet outside the Solar System."

MarkusQ 4mo ago
The GP post's point was that, logical as this would be, the IAU definition explicitly states that planets are "in the Solar System". So no, exoplanets are exoplanets, not planets. And Pluto isn't an example of either.
- jibal 4mo ago
  No, The IAU definition does not say that. You and others are confusing the definition of a planet with its application to planets in the solar system (and thus to Pluto) -- IAU Resolution 5A: Definition of a Planet in the Solar System. The IAU of course does not assert that only planets in the solar system are planets ... that would be ridiculous, and the interpretation of the IAU's stance as being so ridiculous is ridiculous and then some. https://science.nasa.gov/solar-system/planets/what-is-a-planet/ https://science.nasa.gov/solar-system/planets/what-is-a-plan... "The definition of a planet adopted by the IAU says a planet must do three things: It must orbit a star (in our cosmic neighborhood, the Sun). It must be big enough to have enough gravity to force it into a spherical shape. It must be big enough that its gravity has cleared away any other objects of a similar size near its orbit around the Sun." https://www.iau.org/IAU/Science/What-we-do/Pluto-and-the-Developing-Landscape-of-Our-Solar-System.aspx https://www.iau.org/IAU/Science/What-we-do/Pluto-and-the-Dev... "More generally, a planet: a. orbits its host star, just as the Earth and Jupiter orbit the Sun, b. is large enough to be mostly round, and c. must have an important influence on the orbital stability of the other objects in its neighbourhood."