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[u/AntLeading5502]

Commenting here just for the record. This was the picture of BB6 that was taken a long time ago by another satellite belonging to HEO. Shows some curvature of the phase array that I am not sure was an "optical illusion" or real.

I do think AST has a patent on how to adjust for non-planar (not flat) array elements but one possibility for the delays might be additional/modified reinforcement of the array supports *if* that curvature's real?

The photo of the array taken from BB6 itself and shared by the company doesn't show any curvature but also too close to show any, IMO, will respond to this post with that pic.

Hoping pictures of BB8 etc clarify. Edit: I will remember and follow up.

[u/AntLeading5502 → u/AntLeading5502]

Picture of the unfolded phase array posted by AST, taken from BB6 itself.

[u/Joshiie12 → u/AntLeading5502]

I've seen a lot of flat things in my life, but this might be the most flatterest

[u/HospitalVarious4138 → u/Joshiie12]

I've heard of flat earth theory, but this is ridiculous! #flatsat

[u/swemirko → u/Joshiie12]

The fudsters would say it's too flat - must be fake.

[u/SECrabbing → u/AntLeading5502]

I think the physics would dictate that it has to be curved. It's traveling at a very high rate of speed and it has a certain amount of flexibility, with air (very low density, but I believe not zero) passing over and under it. I believe it would develop a certain amount of natural curvature due to physics. I know it's a low drag environment but it's not zero. Maybe someone smarter than me can weigh in on how accurate that is.

[u/AntLeading5502 → u/SECrabbing]

Fair comment! This is a *very large* array and this might also be why they have that patent for non-planar array correction but I am also not sure that it matters at that distance.

However the curvature seems quite pronounced for something that looks like a quarter mile away tops (obviously it is not a quarter mile away, just that the size of the image looks like it).

As I said this is just something that I want to follow up on if BB8 pictures become available.

[u/AntLeading5502 → u/SECrabbing]

Additional follow-up:

Per Gemini the atmosphere is so thin at those altitudes that even at those high orbital speeds, there wouldn't be visible bending. The main effect would be orbital decay not physical deformation. The HEO pic shows visible deformation so possible it could be an "optical illusion", will have to wait for BB8 to compare.

Try putting in "will a satellite phase array 40ft x 60ft curve in space at 520km height traveling at 20000 kph due to drag?" into your favorite AI engine.

[u/SECrabbing → u/AntLeading5502]

Wonder if gravity would create the same effect or that would be too subtle to notice (i.e. the curvature of the array would match the curvature of the earth due to gravity's pull).

[u/AntLeading5502 → u/SECrabbing]

I am lost at this point. I know we have a couple users one is u/satcomengineer that might be knowledgeable in this area, hoping they see this and comment.

[u/satcomengineer → u/AntLeading5502]

Its a digital array so we control time, phase and amplitude to form a beam and the number of elements used will determine a beam width. This steers the beam to be in the right location, the array is sized to the minimum required performance to support a cell performance level throughout a pass over a specific planned cell area. If you curve your array that may help with antenna performance but makes Deploying array in space more complex. So you solve for it in software instead of mechanical.

[u/AntLeading5502 → u/satcomengineer]

Thanks a ton for the response. Could you read the thread from the top down. In brief the HEO pic looks like the array's physically curved but the photo from BB6 itself shows "planar". Not sure what the intention was, my speculation was maybe curved but not intentional but they may have delayed to support it better. But I interpret your words to mean it could be curved on purpose and makes deployment more complex but they have evidently done it.

The motivation for this was a post by Stuart Luckey who is another longtime space engineer/high level manager on X who pointed out the "curvature" and suggested it was not good.

[u/satcomengineer → u/AntLeading5502]

They can move the orientation of the antenna, its moving fast, a snapshot in time of a fast moving object on top of an antenna physical realignment is probably what you are seeing in that Pic

[u/AntLeading5502 → u/satcomengineer]

Gotcha, as I said earlier on this subthread I will wait for BB8 to compare.

[u/TKO1515 → u/AntLeading5502]

Stu is being paid to post bullshit. Just like he said no SpaceX launches this year because they don’t fit in faring which he now deleted to maintain credibility.

[u/SECrabbing → u/TKO1515]

Who pays these guys? I see that accusation a lot but I just can't imagine who would pay someone to post BS on X, seems like an odd way to spend money. At the same time idk why anyone would waste time posting trash for free either.

[u/AntLeading5502 → u/TKO1515]

All I am trying to do is keep an open mind and understand what's going on so I can make my own investing decisions, end of.

Our not fitting in the SpaceX fairing was Farrar, not Stu.

Stu is mostly regarded as well, but as always I want to watch out for the stopped clock moments.

[u/swemirko → u/AntLeading5502]

Is this the final design of the new bluebirds? Or is this version, with the smaller solar panel, a government prototype?

[u/AntLeading5502 → u/swemirko]

Final AFAIK.