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In English we have a saying "window of opportunity" which means that there is specific time period where a certain event can occur.

Based on that expression we talk about a "launch window" when it comes to rockets going into space and what-not. Due to weather or whatever other factors beyond human control, it is only possible to launch a rocket on certain days, or the "launch window".

I was reading a Japanese news article on the "scientific rocket" that North Korea plans on launching (who's launch window opens today), and they use the phrase 「発射通報期間」. According to dictionaries this means "Firing/launching report period", but I imagine from the (very clear) context that this would be "launch window" in English. Now, while from the context of the article, I know the meaning, but my qeustion is if it is specific to talking about rockets and the like, or if something can be substituted to talk about, for example, a job offer (i.e. 求人通報期間?). Is there a phrase, idiomatic or otherwise, to convey a "window of opportunity"?

As a secondary question, what exactly does 通{つう}報{ほう} mean in this context? I mean, does it have a meaning other than "report; tip; bulletin; message"?

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I think you are actually misunderstanding the concept of a launch window; it's not to do with weather, but rather with the motion of the target (the moon or whatever). You have to time the launch so your target will be where you plan to be at the time you plan to meet it. Which also means that missiles like North Korea's, designed to just go up and then down again rather than hit a moving target, don't have launch windows at all. (See Jesse's explanation of what 発射通報期間 actually means). – Matt Apr 13 '12 at 0:19
@Matt: Oh I know that, I just didn't think it was important to explain everything in my question...that's what I meant by "whatever other factors beyond human control" :) – silvermaple Apr 13 '12 at 0:57
up vote 9 down vote accepted

Is there a phrase, idiomatic or otherwise, to convey a "window of opportunity"?

As you may have noticed, in English, "window" conveys a period of time, that is why you can say "launch window" and "window of opportunity". To convey "window of opportunity” in Japanese, there are several phrases that come to mind:




※Side note, you can replace 好機 and 機会 with チャンス making チャンス到来 and 絶好のチャンス which I feel makes it more conversational.

However, I think you might be looking for a phrase in Japanese that can be used idiomatically like "window" is used in English. Unfortunately, there is no phrase that exists because this is an English idiom.

As a secondary question, what exactly does 通報 mean in this context? I mean, does it have a meaning other than "report; tip; bulletin; message"?

No, there is no special meaning here. 通報 is the act of informing or the message itself. North Korea said they were planning on launching a missile within a certain period of time, so the 発射通報期間 is the period in which they said they were going to launch the missile.

By the way "launch window" in Japanese, is 打ち上げウィンドウ.

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Thanks :D I thought it might come down to ウィンドウ in the end, heh... – silvermaple Apr 13 '12 at 0:59

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