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Summer Triangle movement - E or NE or..

Started by JesterDev, 07/12/2006 04:22AM
Posted 07/12/2006 04:22AM Opening Post
Tonight I went outside while at work to my usual area's around the building, and I noticed that the summer triangle is further E (or NE) then it was the last time I looked. This could be due to the fact that I have normally looked at it later in the night then I did tonight. I tried going out agian about an hour later and the clouds have moved in over the area so I cannot tell where it has moved too.
So my question is in what direction is it going to move as the summer goes on? The reason I'm asking is that I am trying to get a feel for where different objects will be in the sky during different times of the year. I have a star chart and what not, but I don't have it with me here at work. And I'm stuck here till 2am.

I also see that Jupiter is setting sooner then it did a month ago. Someone here told me that it will be gone for several months soon. So I am at least getting a grasp of where things are, and their basic movement.
Posted 07/12/2006 08:10AM #1
The stars appear in the same spot they were in the night before 4 minutes earlier each night, that is not a lot, but it is how we get the different stars in the sky during each season. Here is a link that will do a pretty good job of explaining it.

http://www.space.com/spacewatch/seasonal_stars_030207.html

Real men play Golf
Posted 07/12/2006 01:48PM #2
If you go out at exactly midnight (or any other time) each night you will see the summer triangle a bit further west than it was last night.

However, if you go out earlier one night than the last, it will appear further east than it was.

The summer triangle does some other weird stuff, though, especially as the summer wears on. As the summer goes on, the sun sets earlier and earlier. Therefore, if you go out an hour after sunset (which happens earlier each night) and look up, you will see the summer triangle hasn't appeared to move much. this is because you are actually looking at it earlier in the evening (further east) but it has moved further west. Therefore, it looks like it is hanging around a long time.

Alex
Posted 07/12/2006 04:11PM #3
Michael,

Yours is a great question, because it is one of the very basic observations that all astronomers must make.

The other posts here pretty much answer your question in words, but there is no better training than to personally watch what happens night after night, season after season. And you're doing that.

I am thinking about an observational astronomy course for people interested in learning about the night sky, and I have thought that this would be one of the final exam questions.

Keep after it and you will learn.

Regards,
Rick

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