Coming up, Launch Director Chuck Dovale takes us through launch day.
Principal investigators David Winker and Graeme Stephens answer questions about CALIPSO and CloudSat spacecraft,
and we'll announce the winning entries from NASA's mission question board.
LSP Chief Engineer Darren Bedell will now explain how the team will launch two satellites with just one rocket.
My name is Darren Bedell and I'm one of the two chief engineers on the Launch Services Program.
For the CALIPSO/CloudSat mission, I've been responsible for overseeing the technical work of our
NASA team that's been integrating the CALIPSO and CloudSat mission on the Delta II.
Each spacecraft is complex in its own right, and so is the launch vehicle.
So when you bring the two together in the typical sense, there are all kinds of technical issues we have to be concerned with.
In this particular case, the temperature requirements between the two spacecraft was the biggest challenge.
The CALIPSO spacecraft needs to be warm. The CloudSat spacecraft, which is the one on the inside of the dual payload attach fitting can,
needs to be cold for its battery charging such that it can have enough power when it gets into orbit to operate properly.
In the past, NASA's flown missions with multiple spacecraft on the Pegasus rocket, which is the smallest in our inventory.
We're doing it now here for CALIPSO/CloudSat on a Delta.
We've seen most of our co-manifested payloads together for low-Earth orbit missions,
and Earth-observing satellites in particular, because they're all going to a similar
orbit and they're performing complementary rolls with each other.
The dual payload attach fitting is a structure that goes on the top end of the rocket, and it goes inside the payload fairing.
The payload fairing is used to protect both spacecraft from the atmosphere as the rocket goes up.
Essentially, the dual payload attach fitting is like a miniature fairing inside of a fairing.
And one spacecraft sits on top of it and one spacecraft sits inside of it.
And what the dual path does is it allows the load or the mass from the upper
spacecraft to be carried around the lower spacecraft and into the rocket.
So, it's basically like putting something inside of a coffee cup and putting another coffee cup on top of that.
CALIPSO's on top; there is a clamp-band which is used on any of the other rockets, as well,
that fires and allows the upper spacecraft, CALIPSO in this case, to come apart from the rocket.
Then the dual payload attach fitting actually has a separation system whereby the can,
or structure which is around CloudSat, is separated and it comes off.
And then they reorient the stage to allow CloudSat to separate from inside of this can that's just been opened up.
I would say probably once every other year or so, we're launching multiple spacecraft.
On launch day, you'll see me as the NASA chief engineer on console,
and what I'm doing there on launch day is to evaluate the readiness of the rocket through various phases of the countdown --
putting fuel in the rocket, turning power on, things like that, and giving the technical go for the program right before we launch.