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We got together and looked at
the very first de-fractional ...


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images that came out of the Webb
Telescope.

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And what we collective saw as a
group is we have the highest ...

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resloution infrared images taken
from space ever.

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So, you think of it as a blub on
a picture, you know, but ...

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it is extremely high resloution.

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We have exceeded every
expectation.

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The telescope performed better
than the models said it should.

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We even achieved, we talk about
resolution and wavefront ...

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quality, we've done better in
those regards than we ...

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thought we do, and we're just
thrilled to death.

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And to get there we went through
a process.

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Well, we did the segment
identification, and then we ...

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formed the image array.

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And then once they were in the
image array we used this ...

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phase retrieval technology to
position each of the ...

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mirror segments and the
secondary mirror itself, ...

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such that, all the optical
aberrations were effectively ...

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eliminated.

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We tilt the mirror segments to
bring the light from each ...

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mirror so that it falls on top
of each other at a ...

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common point in the middle of
the detector.

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And we call that image staking.

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And that concentrates all the
light in a single place.

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But the segments themselves are
not cooperating, they're ...

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not working together at that
point.

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They're all their own individual
telescope.

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And the next phase of the
process is something we ...

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call course phasing.

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And that is where we adjust,
literally its the piston, ...

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its the up and down motion of
the mirror segments relative ...

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to each other.

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We control the piston of the
segments so that they all ...

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come together in creating a
complete monolithic ...

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primary mirror.

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If you know exactly what the
shape of that telescope ...

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is, and you know exactly how the
light is falling on your ...

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detector, it turns out that you
can prove, you can actually ...

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prove mathematically that, that
is enough information to ...

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tell you exactly what you need
to do to that telescope to ...

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fix the alignment errors.

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And why do we know this?

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We know this because of
something called the ...

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pupil imaging lens.

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And this allows us to take a
picture of the ...


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primary mirror of the
telescope.

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People refer to it as a selfie,
well that’s what it is actually.

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But that’s really important
mathematically.

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Now there is a catch however.

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Just because you know a solution
to something exist does not ...

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automatically give you that
solution.

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And that is the difficult part.

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That what we’ve spent 20 years
working out.

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Its highly mathematical, uses
something Fourier analysis.

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But that’s what we do, is we
tease out those solutions, ...

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and we find what we need to do
to each optical element ...

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to achieve perfection.

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We then turn to a different way
of doing phase retrieval.

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Across the entire aperture of
the telescope at the ...


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same time, and for that we’re
not going to take the ...

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telescope out of focus.

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Instead we some lens that are in
one of the ...

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science instruments that we use
to automatically to create a ...

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defocused image.

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And we look at these images, an
taken as a whole, then ...

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we can tell the last little bit
of alignment errors in the ...

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telescope that we need to fix.

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And that is what we accomplished
today.

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We analyzed those images and we
applied the corrections ...

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leading to the de-fractional
imaging, the perfect ...

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performance of the telescope.

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So there is only one thing left
to do, and that’s to see how ...

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well the telescope is aligned in
the other science instruments.

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And we’ll check the alignments
there, and if necessary ...

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we’ll apply a solution that
optimizes for the ...

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entire telescope.

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We then periodically measure the
alignment of the telescope, ...

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and made corrections as
necessary.


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I cannot wait to see what it
discovers.

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