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James Webb launch Dec 25th

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Loveall

Loveall

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Anyone excited about the James Webb space telescope launch? Will it finally happen after all these delays?

It can be followed live on NASA's youtube channel. 7:20 EST.

One thing I can't figure out is why are they launching it in the morning? It is supposed to get to an orbit around L2, over a million km towards the sun. Why not launch it on the afternoon (sunset) when the launch site is moving away from the sun? I would think that an boost away from the sun from Earth's rotation would be advantageous???

What am I missing :?
 
Cool! Will have a watch with the fam. Regarding the gravitational assist: I can’t imagine they didn’t figure out all the best loopyloos, probably has something to do with wherever the best series of passes happen to be around the vicinity of the launch date.
 
roninsina said:
Cool! Will have a watch with the fam. Regarding the gravitational assist: I can’t imagine they didn’t figure out all the best loopyloos, probably has something to do with wherever the best series of passes happen to be around the vicinity of the launch date.
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Well, they are not using gravity assists as I understand it. Just going to L2 on it's own power. I'm sure there is a reason forming launch, just wondering what I'm missing. They launch for the equator for the rotational assist, but it's in the opposite direction as I understand things.The moon would be out of the way (gravitationally) in the afternoon too.
 
When I first read the initial launch date of December 22nd I told my son it would be December 25th because time is not linear like we think it is and that's how the "Christians" can make the narrative of the wise men and 'North Star' fit. The James Webb telescope is the North Star described in the Bible (wouldn't it be strange if that's actually true, truth is always stranger than fiction so I personally would not be surprised)

I'm excited, super excited. I'm looking forward to learning atmospheric conditions in Alpha Centauri, Alpha Proxima and our other neighbouring solar systems. Its my understanding there are at least 6 planets in the habitable zone within 40 light years from our planet. I also know there will be further observation on Ton 618, Sagittarius A and Neutron Stars, all of which are fascinating and the latter of which I personally believe to be far more terrifying than the former. I feel drawn to the stars. It's almost as if I was an astronaut in a former life but only one passed before my coming so that would be a huge coincidence (or time isn't linear)
 
Maybe that, given the pull of earth's rotation, launching in the evening would make it shoot beyond the optimal trajectory. When you launch in the morning you have a whole day to get away from earth, using that slingshot effect. Then you can adjust your trajectory when you're right in front of the ideal, shortest path to L2. Would be my best guess.
 
dragonrider said:
Maybe that, given the pull of earth's rotation, launching in the evening would make it shoot beyond the optimal trajectory. When you launch in the morning you have a whole day to get away from earth, using that slingshot effect. Then you can adjust your trajectory when you're right in front of the ideal, shortest path to L2. Would be my best guess.
Click to expand...

Yeah, it looks like this is what is going to happen. What confused me is that in the images I saw first (see first image below) it looks like a straight shot to L2.

However, a look at the second image below with a little more detail around the earth makes things clearer. The satellite leaves to L2 on the left side of the earth (sunset location). Therefore when it launches in the morning it must go into a low earth orbit over the Pacific ocean, then when it gets above the side of the earth where sunset is happening (~half an orbit), it accelerates and leaves earth's orbit towards towards L2. The Ecuadorian rotation push helps it get there since that energy was put into the near earth orbit.

The confusion I had was because a matter of scale. One can't see the earth orbit part of the trip well because it is very small compare to the distance to L2. I would add an informative inset if it where my drawing 🤷‍♂️

This page describes the launch sequence well. I believe the stage separations happen while I
orbit above the earth, and the fin burn finishes above the sunset location on earth.
 

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Maybe if we smoalk enough we can catch up to it and visit it. :twisted:

Wonderful news, really exciting, and am looking forward to interpretations of data it collates as well as purrrttttyyyyy new pictures.

Thanks loveall.

One love
 
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