WEBVTT

00:00:00.000 --> 00:00:11.000
GEORGE DILLER: With us now is Jim Adams, who is the deputy project manager for STEREO from NASA's Goddard Space Flight Center in Greenbelt, Md.,

00:00:11.000 --> 00:00:20.000
and we asked Jim to come over and talk to us a little bit about what will happen to STEREO as soon as it separates from the rocket tonight.

00:00:20.000 --> 00:00:29.000
We will get through all of the Delta II activities, the functions of the rocket, by 25 minutes after launch. At that point,

00:00:29.000 --> 00:00:33.000
STEREO separates and then its activities are really just beginning.

00:00:33.000 --> 00:00:38.000
So we have some animation now that we're going to roll and would like Jim Adams to tell us now,

00:00:38.000 --> 00:00:42.000
as soon as STEREO comes off the rocket, what are the things that are going to be happening?

00:00:42.000 --> 00:00:51.000
JIM ADAMS: And of course, what you've just seen, George, is the animation of the satellites going into the fairing. As soon as we come off the rocket,

00:00:51.000 --> 00:00:56.000
two minutes after we separate from the third stage, the two satellites will separate themselves automatically.

00:00:56.000 --> 00:01:06.000
And two minutes after that, at two minutes after that, then the two satellites will automatically deploy their own solar arrays.

00:01:06.000 --> 00:01:13.000
First the inboard arrays come out. You can see that on the A satellite in the foreground and then the B satellite in the background.

00:01:13.000 --> 00:01:20.000
They will allow the solar arrays to settle out and then a few seconds after that, then the outboard arrays will deploy and everything will settle down,

00:01:20.000 --> 00:01:29.000
first on the A spacecraft and then on the B, as you can see.

00:01:29.000 --> 00:01:36.000
What will happen after that is then the two satellites will continue in the slow drift to Canberra.

00:01:36.000 --> 00:01:41.000
It'll take about 30 minutes before they come up over Canberra and we can make contact with them with the Deep Space Network.

00:01:41.000 --> 00:01:54.000
Once the Deep Space Network makes contact with the satellite, that's when we will begin to stabilize the satellites and begin to deploy the high-gain antenna.

00:01:54.000 --> 00:02:03.000
The high-gain antenna, in this animation, you can see has already been deployed. But a little later on, you'll see some of the other deployables come out.

00:02:03.000 --> 00:02:08.000
The satellite itself has a number of deployables. There's the high-gain antenna that, that just went out,

00:02:08.000 --> 00:02:20.000
and that allows the satellite to communicate all the data back to Earth at the high-data rates that will make the images that STEREO collects so stunning.

00:02:20.000 --> 00:02:25.000
Also, we have a cover over the heliospheric imager, which needs to, which protects it from the launch environment,

00:02:25.000 --> 00:02:32.000
as well as a six-meter boom that deploys out some of our in-situ particle measurements.

00:02:32.000 --> 00:02:37.000
And there you can see some of the smaller doors over some of the base particle measurements.

00:02:37.000 --> 00:02:48.000
Those two doors that are deploying there and the third are the three main telescopes onboard the STEREO satellite that will eventually fuse into 3-D imagery.

00:02:48.000 --> 00:03:00.000
The satellites will take off around the moon. They'll do a slingshot around the moon and separate in their journey to change the way we look at the sun.

00:03:00.000 --> 00:03:04.000
DILLER: So, relative to Earth, the two spacecraft will be how? How are they...

00:03:04.000 --> 00:03:12.000
ADAMS: Relative to Earth, one will be out in front of the Earth, leading the Earth in its journey around the sun,

00:03:12.000 --> 00:03:14.000
and the other will lag the Earth in its journey around the sun.

00:03:14.000 --> 00:03:28.000
The Earth goes around the sun in 365 days. The head spacecraft will go around the sun in 364 days, and the behind spacecraft will go around the sun in 385 days.

00:03:28.000 --> 00:03:33.000
DILLER: Now all the deployments that we saw in the animation there, how long is that? Is that like a day, a week, or...

00:03:33.000 --> 00:03:34.000
ADAMS: That takes place over about four days...

00:03:34.000 --> 00:03:35.000
DILLER: Four days.

00:03:35.000 --> 00:03:42.000
ADAMS: After about four days, we'll have all of the deployables out and we'll be prepared to open the doors on our most sensitive optics.

00:03:42.000 --> 00:03:47.000
DILLER: Now at what point tonight will you be comfortable that STEREO is fine?

00:03:47.000 --> 00:03:59.000
ADAMS: Roughly after we come up over Canberra, which is one hour after launch, and then what we'll be doing is executing a de-tumble procedure,

00:03:59.000 --> 00:04:05.000
so and hour and 15 minutes, we should know that STEREO is power positive and stable,

00:04:05.000 --> 00:04:12.000
communications systems are working and the thermal control is all under, as we planned.

00:04:12.000 --> 00:04:20.000
DILLER: What are some, some ways that we could think about the STEREO mission? What are some ways to, you know, to recall what it's going to do?

00:04:20.000 --> 00:04:23.000
ADAMS: Well, I use a couple of tricks. And I realize this isn't really a science briefing

00:04:23.000 --> 00:04:27.000
but I usually tell people to remember the number seven, to remember the number four, and to remember the number two.

00:04:27.000 --> 00:04:32.000
Seven, four and two -- they kind of don't seem related, but in fact, they are.

00:04:32.000 --> 00:04:44.000
Seven relates to the number of tons of hydrogen at the sun's core, fused every second into helium.

00:04:44.000 --> 00:04:49.000
That powers the solar system, and basically sustains life on Earth. The number four relates to the four reasons why we should care,

00:04:49.000 --> 00:04:59.000
and that is that the coronal mass ejections, the solar wind,

00:04:59.000 --> 00:05:06.000
the solar flares that are constantly coming off the sun and interact with the Earth's environment, affect us in four ways, and that is power distribution,

00:05:06.000 --> 00:05:16.000
satellite in communications, astronaut radiation environments, and airline traffic.

00:05:16.000 --> 00:05:20.000
Certain airlines have begun to limit polar routes in periods of high solar activity. So that's seven tons, four reasons you should care,

00:05:20.000 --> 00:05:33.000
and two, because STEREO is now going to be two eyes in the sky instead of one.

00:05:33.000 --> 00:05:47.000
DILLER: Well, Jim, thanks very much and I know you have a team here at the ground station that's watching very closely what's going on in the countdown.

00:05:47.000 --> 00:05:51.000
And I guess it's the team here in Florida that actually commits it to internal power, is that correct?

00:05:51.000 --> 00:05:58.000
ADAMS: That's correct. We'll go on internal power just six minutes before launch, and right now, everything's looking green.

00:05:58.000 --> 00:06:01.000
Everything is nominal. We're having absolutely no problems at all.

00:06:01.000 --> 00:06:02.000
DILLER: Well, Jim, thanks very much.

00:06:02.000 --> 00:06:08.000
ADAMS: You're welcome, George.

00:06:08.000 --> 00:06:08.000