Use of the word "emit"

I came across this article http://www.ibtimes.co.uk/scientists-discovers-light-emiting-mysterious-alien-planet-338945. The web link uses "emitting" in an attributive manner which we have all seen many times. For example "light emitting diode." The title, though uses emitting in this way "Scientists discover light emitting from mysterious alien planet." The first sentence of the article uses "emanate": "Scientists have detected light emanating from..." It's almost like the writer couldn't make up their mind which word to use or wanted to add "variety."

I have seen "emanate" used more often, and to me seems correct. I'm not sure why (which is why I'm asking) but it seems to me that grammatically, "emitting" can't be used the way the writer wants to use it. "Emit" is a transitive verb and I have seen it many times used in "X emits Y" constructions. I feel the sentence should be "Scientists discover light being emitted from mysterious alien planet." (A side question is whether the preposition "by" should be used and not "from.")

The question is, "Is the verb "emit" being used correctly? Why or why not?"

Solution 1:

I agree with you that light cannot emit from something. I think that the difficulty is that "The planet emits light" is not a causative, comparable to "The sun melts ice". The latter can be paraphrased: "The sun causes ice to melt", and it implies that "Ice melts". If "emit" were a causative verb like "melt", "The planet emits light" could be paraphrased: *"The planet causes light to emit", but it can't be paraphrased like this, because *"Light emits" is nonsense.

The authors of the article might not be to blame, because headlines are often composed by others.

Solution 2:

It sounds odd to me as well. As you say, "emit" is generally a transitive verb. That said, the OED does list this intransitive use of "emit" [from] without comment; it has one example from 1886. That example is also from the press, so the writer might not have been using the word very carefully.

(b) intr.

• 1886 Daily News 16 Sept. 7/2 Summoned..for..permitting..smells to emit from his stable.

A look at Google Ngrams does support your statement that "emanating from" is more common; apparently overwhelmingly so:

A search of Google Books turns up some other examples of this use of "emitting from":

Thus, the LED schematic symbol has light emitting from, or coming out of, the diode. That's why it's called a light-emitting diode.

(Semiconductors: From Book to Breadboard, by Kevin McGowan)

A somewhat comparable case might be the rare intransitive use of transmit to mean "to be transmitted", which seems confined to specialized legal contexts. The OED gives the following examples:

b. intr. (for refl.) To pass to the heirs.

• 1913 H. Goudy in Ess. Legal Hist. of Congr. Hist. Stud. 208 Where..a delictal action was not strictly penal..it transmitted both actively and passively.
• 1913 H. Goudy in Ess. Legal Hist. of Congr. Hist. Stud. 218 In contracts the right of action almost invariably transmitted both to the heirs of the creditor and against the heirs of the debtor.

I would recommend always using "emit" transitively, but I'm not sure I would go so far as to call an intransitive use grammatically incorrect.

Solution 3:

The word "emit" means "send out" or "send away from". The 'e' (or 'ex') prefix (from the Latin 'ex') generally means "out" or "outward" and the suffix 'mit' means "to send" (from the Latin "mitter").

So when we say "the planet emits light", we mean "the planet sends light outward". If we turn it around and say "light emits from the planet", we mean "the light is sent outward from the planet". A phrase like "light sends outward from the planet" seems weird, so it seems like the more correct usage would be "light is emitted from the planet". In the example sentence, "scientists discover light being emitted from the planet" makes more sense.

That said, I've heard phrases like "it emits from" or "it's emitting from" many times over. I've never heard of light "emanating" from something that I can recall, though the usage makes perfect sense. I have heard of other things emanating from something, just not light.

In my head, "emanating" is a more figurative, fancy word. To me, "emitting" has the same meaning except it's just an ordinary word I'd bother to use in everyday speech. Not saying that's the definition, but it is my personal experience.

Of note, I know of at least "issue" which is often used in the sense of "it issues forth from" despite also meaning "to send forth".