Space Grammar Nazis who also get really het up about kerning.
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Of course! And that’s exactly why people talk about whether certain animals are sapient, rather than sentient, because obviously they feel things!
Usage trumps semantics, even when it’s annoying. Personally, I could care less.
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I think I read somewhere that if you follow the modern astronomical definitions of moons and planets the earth-moon system is actually considered a binary planet system, because the masses being so similar. That would actually make the moon a planet in an astronomical sense 
I think is defined to be a moon anyway so as not to invalidate ages of astronomical books.
Christ.
On.
A.
Bicycle.
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Once again, many astronomers and astrophysicists DO refer to the Earth-Moon system as a “binary planet” =). I’m quite aware of the “official” IAU designation, thank you. I’ll also reiterate here, that Pluto WAS a “planet” until recently (and apparently may very well be again); as I said above, things change.
Our moon’s name is “Luna”; our sun’s name is “Sol”.
Although Sol III has a lot of names (Earth, Gaea, Tellus, Prithvi, &etc.) she usually goes by “Terra” when she’s got her hair down.
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The legacy started by Ronny Raygun… sigh…
Nice! I liked Michael Hedges a lot but between him not exactly being a superstar to begin with and dying so young it’s so rare to see any references to him anymore.
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In between sets, at the Fox Theater in St. Louis, Missouri, he was in line at the cash bar with me. He asked me how I ended up with so many braids (I had really long hair back then, and he did too).
“Did you do that yourself?” he asked.
I did.
“How?”
“I pulled all my hair back into one elastic band, then pulled half-inch widths piecemeal, until every strand of hair was in a small braid,” I answered.
I got the sense he hadn’t a hairdresser or partner any more than I did. He gave me the understanding he was going to be trying this himself soon. He was open and friendly and, though this word gets used a bit too often in 2017, he was authentic. No ego. I miss him and his music. I am not a superfan, but it was clear to me that he was gifted. I was sad when I heard he passed so unexpectedly. The fact that David Crosby [and Graham Nash] worked to get Hedges’ posthumous album out…
… just secured my notion that he did possess something real, a talent, a fresh way of playing and having something to say with his music. (IMO, anyway, since I think Crosby is a pretty good musician as well, even if I sometimes find his personality kinda grating.)
In Austin, where I live now, I’ve seen a lot of musicians really solid on technique, but without a lot to “say” with their technique. Having such a nexus inside a soul who then pursues public expression of it is no small thing. It’s risky in a lot of ways, but when someone pulls this off–what a gift to us. We were lucky to have Hedges for the span we got him for.
Ad astra Michael Hedges, and peace be with you.
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I really don’t get your position. At one time, you claim that using the correct and current nomenclature, which distinguishes between stars and planets, is 3rd grade stuff, which implies that reasonably educated adults should adhere to this standard. But when those standards, as set by a body of astronomers which regularly oversees the definitions, don’t match with your liking, it’s suddenly all semantics and “times changes”.
Sorry, you can’t have it both ways. Because “Earth Moon isn’t a binary-planet” is 3rd grade stuff.
And many astronomers and astrophysicists don’t agree, that simple.
There are TWO definitions of binary planet (one by relative mass of the objects, one by an external barycenter); the IAU simply decided on one =). Both, however, are still commonly used. In other words, a self-selected “standards body” doesn’t necessarily force anyone at all to use their standards, to this day - lol.
No matter how you argue, this IS true and easily verified.
https://www.windows2universe.org/pluto/binary_planet.html
In fact, the IAU definition of “planet” doesn’t allow for binary planets at all! (Yet they still go on to define a “binary planet” =) ).
(From Universe Today)
First, it’s important to understand what the official definition of a “planet” is, at least according to the International Astronomical Union. In its own words, according to a vote in Prague in 2006, the union has this definition:
“A 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, and (c) has cleared the neighborhood around its orbit.”
What this means is that a planet must move around the Sun (and not move around something else), that it’s massive enough to have a round shape due to gravity, and that it will swoop up any dust or debris in its orbit as it moves around the Sun.
But let’s be clear on something; the IAU definition of planet is not without controversy. There is still a strong contingent of people who say that Pluto is indeed a planet, including the principal investigator of a spacecraft (New Horizons) to examine the world: Alan Stern.
“It’s an awful definition; it’s sloppy science and it would never pass peer review,” he told the BBC in 2006. He said that the line between dwarf planets and planets is too artificial, and that the definition of a “cleared neighborhood” is muddy. The Earth alone has many asteroids that follow it — or approach or cross its orbit — not to mention the massive planet Jupiter.
The Moon is not a unique phenomenon in our Solar System, in the sense that there are other planets that have satellites around them. Jupiter and Saturn have many dozens! Referring again to the IAU, the union also said in 2006 that it does not consider Charon a dwarf planet despite its large relative size to Pluto.But Charon’s status as a moon could change in future, the IAU acknowledged. That’s primarily because the center of gravity in the system is not inside of Pluto, but in “free space between Pluto and Charon”. This center is called the “barycenter”, technically — and in Jupiter and Saturn’s cases, for example, all the barycenters of the various moons reside “inside” the huge gas giants.
Another caution, however: the IAU says “there has been no official recognition that the location of the barycenter is involved with the definition of a satellite.” So for now, it doesn’t have any bearing. That said, one question to consider is if the Moon’s barycenter is inside the Earth?
The answer right now is “yes”. But over time, that barycenter will move outside of Earth. That’s because the Moon is slowly receding from our planet at a rate of about 3.8 centimeters (1.5 inches) a year. It’ll take a long time, but eventually the center of our system’s mass will not be within our planet.
And if you read back to an IAU interview in 2006, you’ll see that at that time, the IAU defined a “double planet” as a system where both bodies meet the definition of a planet, and the barycenter is not inside either one of the objects. So for now, the Earth is a planet and the Moon a satellite — at least under IAU rules.We have written many articles about the Moon for Universe Today. Here’s an article about how long it takes to get to the Moon, and here are some interesting facts about the Moon. We’ve also recorded an entire episode of Astronomy Cast all about the Moon. Listen here, Episode 113: The Moon, Part 1.
So Pluto/Charon are NOT a “double planet”, even though they have an external barycenter, hmm? And the Earth/Moon system, in contrast, doesn’t have an external barycenter, but will eventually.
You can stop trying to pick nits now; “there has been no official recognition that the location of the barycenter is involved with the definition of a satellite.” Back to 3rd grade with you!
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