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We're here at the Jet Propulsion Laboratory
in Pasadena, California, home of Mars rovers.
But it turns out the folks working here
are doing a lot more than that.
And I just happen to have here Dr. Mike Ressler.
He is a MIRI project scientist.
MIRI project Scientist-- a mouthful.
What do you do in a nutshell?
So MIRI is an instrument that will fly on the James Webb
Space Telescope.
And it's sensitive to infrared light rather than visible
wavelengths.
So we can see the heat from astronomical sources rather
than the visible light that you see
if you look through a telescope with your eyes.
You are in charge of the production of the detectors?
What exactly is the detector?
The detectors are the sensors.
So if you have a digital camera, there's
a little electronic chip in the heart of the camera.
And that's the sensor.
It's what gathers the light from the lenses
and converts it into a picture that you can look at it
on your computer later on.
So the instrument that we're working on
does exactly the same thing.
Let's take a look at it.
And I think we have to get into bunny suits.
Is that right?
Well, smocks, to keep things clean.
So much for getting my hair done today.
One size fits all?
Or one size fits none.
Oh.
We have a light source, basically
a very sophisticated little light
bulb, that's mounted in our test setup that's
shining on the detector.
And the detector is collecting light in steps.
We can see that the detector is indeed very sensitive.
It responds very well to light.
By where it saturates, we can tell how bright
a star we'll be able to look at once James Webb actually
launches.
All those bright spots are bright because they're
supposed to be--
No bad pixels, no hot pixels--
everything's just as it should be.
The detectors go through environmental tests.
They're shaken and chilled to make sure they
survive the rigors of space.
So now it's time to do a final inspection of the unit
to make sure nothing's happened to it
while we were doing the testing.
So we want to check it to make sure that nobody accidentally
got a fingerprint on it.
We want to make sure there are no broken wires
or other damage to the unit.
We want to make sure everything is just fine.
So we're really wrapping up.
And we're able to say this module is fully
qualified and ready to go.
The Mid-Infrared Instrument or MIRI
has three detectors, all of which
have to be precisely aligned with each other
to within half the width of a human hair.
Thanks for taking this tour with us Behind the Webb.
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