GEORGE DILLER: This is Delta Launch Control at T-69 minutes, 53 seconds and counting.
And we're joined now here at the console by Ed Reynolds, who is the
STEREO project manager from the Applied Physics Laboratory of Johns Hopkins University in Laurel, Md.
And, and Ed has been here for quite some time now with the STEREO spacecraft, preparing it for launch, and so, Ed,
this is certainly a big day for you because it looks like we have a very good, good chance for a launch tonight.
Ed, we're going to roll a tape right now and it's what the spacecraft went through when it was at the
Astrotech Payload Processing Facility, and you can tell us some of what, what was going on when some of these things occurred. So...
REYNOLDS: OK. DILLER: Let's go ahead and roll the tape.
REYNOLDS: OK. This is us arriving at Astrotech in Titusville in early May, and we trucked the spacecraft
down from Maryland, and each spacecraft traveled in its own shipping container. And we go through a lot of trouble
to keep the spacecraft extremely clean through the buildup and through the testing, and even through the transport.
So what you're seeing is, you're seeing some of our engineers, they're unloading, unloading the shipping containers
in the loading dock, and then they prepare the, the spacecraft to go into the
clean room. And here you see a laminer flow clean room at Astrotech.
The spacecraft are still bagged, and key things to point out is you can tell just, just the cleanliness we go through.
We have, everyone is in clean room outfits, basically protected to the point that only their eyes are showing,
and then the spacecraft are double-bagged and we keep nitrogen purges on them.
When we arrived at Astrotech, a lot of the things that we did was just functionally testing the spacecraft to
make sure that it survived the ride, that its, its fit was fine, its performance was working.
We did a lot of repeat of testing that we did in Maryland during the buildup of the,
of the spacecraft and the environmental test program.
Here you see the, a deployment test of our high-gain antenna, and this is what we use to downlink all of the
images and all of the science data that we collect while we are on station. Right now, what you're seeing is just a,
a walkout of the solar arrays, just to make sure that the fit is still
good and that they will work and deploy shortly after launch.
What you're seeing here is, is we have to put propellant into the spacecraft, and we, we launch our spacecraft
into phasing orbits, and we use propellant to do propulsive burns, to line them up to go past the moon,
and so we have to, we have to load a significant amount of propellant on the spacecraft.
DILLER: Is this actually the two spacecraft being mated together?
REYNOLDS: Yeah. Here we're mating the two spacecraft just as they sit on the rocket. It's one Delta II rocket,
but two spacecraft -- one on top of the other. Here the spacecraft are fueled. They're bagged for contamination reasons,
but we're preparing it to undergo spin balance, and this is to, for us to get a precision
injection using the third stage of the, of the Delta II. So we, we stack the spacecraft, we put it on the spin table,
we start spinning it up, and any imbalance that we measure, we basically start trying to balance out the spacecraft
by adding extra balance weight or removing balance weight that we had put on the observatories early in our test project.
And it turned out that the spacecraft themselves were very well balanced, and in this test, we actually were
taking balance mass off the spacecraft. Here we're going through what's a, called a black-light inspection.
We use just, you know, black light to try to get contamination to glow if it's present, and it's, it's a good
way for telling just how dirty or how clean the spacecraft is and how good our cleanliness program is.
And we do that for the, the optics on board.
Here you see the spinning. When we spin it, we spin it up to the same types of rates that we'll see on the Delta rocket,
which is about 50 or 60 rpm. Here we're preparing the, the spacecraft stack. We've mated to the third stage of the
Delta rocket at the Astrotech facility, and the entire stack, the third stage and the two observatories,
are put onto a transport dolly, and then the transport, and then the stack is, you know, again it's bagged
and then we put a protective can over the, the entire assembly.
And this is how we travel out to the launch pad.
And the, the travel to the launch pad, it's a, it's a slow, it's a slow pace, about five miles per hour.
It's about a 20- to 25-mile journey from Astrotech to the Boeing pads. We're doing this, we're leaving Astrotech here
about midnight and we're arriving at the pad early, early in the morning, right as dawn is breaking on the pad.
DILLER: You mentioned that, that STEREO is a very contamination-sensitive spacecraft.
What is it that's on the spacecraft that makes it that way?
REYNOLDS: Well, we're looking at, we, we have coronagraphs onboard. What a coronagraph is, it's an imager
with a disk that, it blocks the, the light from the ball of the sun. And we call that an "occulter."
And we're interested in, in the imagery that's, that's coming off the sun, essentially in the corona.
And if you start having contamination floating around your spacecraft, the light from the sun will actually light
up that contamination and that gets picked up by your, your optical sensor,
and that starts polluting the picture that you're trying to take.
We also have an ultraviolet imager as part of that optical payload and,
and ultraviolet instrumentation is very sensitive to contamination.
DILLER: You have a ground station here, but a lot of what's coming up is actually
going to be happening at the Applied Physics Laboratory, isn't it?
REYNOLDS: That's right. We have, we have command consoles down here that help us, give us some flexibility in our testing,
but the mission operation center is in, is in Laurel, Md., at APL. We're actually running the countdown
right now from Maryland, and we're using data lines that flow down from Maryland to Florida and,
and we're sending commands to the spacecraft from Maryland and we're watching that telemetry back in
Maryland while everything, you know, while everything's down here in Florida.
DILLER: Well, this is launch day, but how long has STEREO been here in Florida being prepared for launch?
REYNOLDS: It's been here since May 3. DILLER: May 3.
REYNOLDS: We're looking forward to getting STEREO off the ground and operating it.
DILLER: Well, thank you very much, Ed. And we'll be following the rest of the countdown,
particularly when we hear STEREO goes to internal power, we know we're, we're almost there.
REYNOLDS: Looking forward to it.
DILLER: Thank you very much. REYNOLDS: Thank you, George.