Yes, this chart is busy. Yes, there’s a lot of small text to wade through.
Still, if you want to understand the science various Landsat satellites have been producing for 40+ years you should set aside 5 or 10 minutes to look over the infographic below. It explains how the instruments carried by Landsat satellites have evolved, and it shows exactly where on the electromagnetic spectrum the instruments on the newest Landsat satellite will collect data. Besides visible light, Landsat sensors look at numerous bands in the infrared, beyond what human eyes can see.
Stay tuned to the Landsat program’s Twitter feed for all the latest updates about the status of the satellite. If all goes well, we should get a first glimpse at LDCM data sometime in the next few weeks. Study now and then you’ll really appreciate that this “first light” will be much more than another pretty picture taken from space.
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I’m standing in an isolated clearing at Vandenberg Air Force Base in California on February 11, 2013, holding an enormous weather balloon. Just as I’m about to let it go, it’s tugging on my arm with four pounds of force.
“Ten seconds. Five. Release Lima 5.”
As the balloon shoots up, I crane my head and watch it shrink away into the blue. It’s sending critical data back to the ground that will help mission managers decide if the Atlas-V rocket on the pad nearby should be cleared to launch the Landsat Data Continuity Mission (LDCM).
As it soars away from the surface, up to about 20 miles (30 kilometers) or more, the pressure is changing. As it does, the balloon goes from being the size of a large yoga ball to that of a school bus.
After the balloon launch, I help the base weather team input data in their office, a small three-roomed building filled with computer screens. When I met the team (see below) early on launch day, they had been releasing balloons for six hours already. As the 10 a.m. PST rocket launch nears, they release balloons every twenty minutes to make sure conditions are right. Richard Stedronsky, one of the meteorologists on the team, says that way the mission isn’t taking any chances.
“We launch a lot of these balloons leading up to flight because everyone needs to know where the winds are, so they can account for worst-case scenario,” he says. “Without these balloons, we wouldn’t know how the winds are behaving throughout the atmosphere.”
He says that monitoring wind shear—the rate at which wind speeds change from point to point—is essential to making sure the rocket gets to where it needs to go. This is especially important for high altitudes. “With the balloons, you know for sure. Yes, it’s going to stay on trajectory. Or if something in the wind profile is changing, they can adjust the trajectory to get the payload into orbit,” he says.
Here I am in the balloon shop, which is essentially a glorified shed that allows the weather team to fill up the balloons with helium without them blowing away. To the left of me is a “low-res balloon.” It looks like a huge birthday balloon. To the right is a “high-res” balloon that looks like what I imagine would be any puppy’s dream, a humongous spiky chew toy that floats.
Low-res balloons, often called synoptic balloons, are released all over the world for weather forecasting, often twice a day; they can expand as they travel up through the atmosphere. High-res balloons are made of plastic and have spikes on the side to increase their stability. To prevent them from expanding as they rise, they have a release valve. They also have shorter strings to make them more stable.
They blow up these balloons by laying them down on a netted table and connecting them to a helium hose.
The hose connects to a truck stacked up with helium.
Then members of the launch weather team, like Stedronsky and Breea Lisko, fasten a radiosonde (a weather-sensing instrument that looks like a small box) and a parachute to help break the radisonde’s fall when the balloon inevitably bursts.
There’s an antennae on the radiosonde; its transponder sends information back on a certain frequency. It comes back to the “antennae farm,” a group of antennae outside the building that feeds it into a computer system in the office. Inside, the Automated Meteorological Profiling System (AMPS) gathers the temperature, dew point, wind speed and direction. The team ingests the data into the system, then feeds it into another real-time system that shares it with the world.
Inside the range weather office, there’s a whiteboard hanging up in the office with the weather information for the launch. Stedronsky points to it and tells me that it reads “whiskey-zero-eight-zero-three-one (WO8031).” They use Julian dates, not standard calendar dates.
This information goes into the systems to initialize the conditions for the balloons. They will use these values to set a starting condition for the radiosondes. Right now, the winds are 1 to 10 knots, the temperature is 6.7 degrees Celsius (44.1 degrees Fahrenheit). The team puts that information into the computer so that the radiosonde takes that as the first data point for its observations and starts recording.
“How is this information important?” I ask.
“As far as these balloons go, if something were to go wrong with the rocket, we have the ability to determine that. If we have to terminate flight, the pieces would land where we want them to land,” says Lisko. The team has to know this information to protect nearby areas from debris. “If something were to go wrong, there would be a lot of chemicals and bad stuff in the atmosphere that we wouldn’t want hanging around. We make sure that the winds are blowing away from populations towards the ocean.”
The LDCM Mission Operations Team successfully completed the first phase of spacecraft activation. All spacecraft subsystems have been turned on, including propulsion, and power has been supplied to the Operational Land Imager (OLI) and Thermal Infrared Sensor (TIRS). The two instruments are currently undergoing a heated dry-out process to ensure water and other potential contaminants are eliminated from the optics and detectors. Cool down of the instruments to enable Earth imaging should begin in a few weeks.
The operations team also conducted a data exchange between the spacecraft, instruments, and ground system for an early look at data processing. OLI and TIRS test pattern data were generated and downlinked to ground stations in Sioux Falls, S.D., Gilmore Creek, Alaska, and Svalbard, Norway. All three ground stations received the data files with no errors, and then the test data were successfully transferred to the USGS Data Processing and Archive System in Sioux Falls, where the data were initially processed and archived.
Thurs. Feb. 7, 2013. Four Days Before Launch, Embassy Suites, Lompoc, Calif.
After arriving at my hotel for my first rocket launch, I started loading up my plate at Sonny’s complimentary breakfast. Not knowing anyone, I walked up to a nearby group of strangers and asked if I could sit down. As it turns out, they were United Launch Alliance folks. Bonding over the fact that we were all here for the Landsat Data Continuity Mission (LDCM) launch at Vandenberg Air Force Base, we got to talking. And because their business is launching things I wanted to know: “Who pushes the button?”
Surprisingly, despite the fact that I was breakfasting among rocket launching phenoms, they said that they didn’t know. And so, my search began.
Fri., Feb. 8, 2013. Three Days Before Launch, Vandenberg Air Force Base.
In the early morning, I ventured out. I questioned everyone at our breakfast table, seeking out likely button pushers amid NASA, Air Force, and United Launch Alliance, LLC employees. No luck.
Some hours later, I asked Rob Lilly, the deputy project manager for LDCM. He told me Omar Baez, the senior launch director in NASA’s launch services program, gives the go.
But, despite my search for Omar, I came up short.
Feeling beleaguered by the day’s search, I decided to head over to Vandenberg Air Force Base.
On base I attended the LDCM press conference. While there, I learned that during the mission readiness review Omar plays a key role.
Meanwhile, in the back of the press conference, I started talking with Captain Benjamin Wauer, a weather officer for the Air Force. He suggested I do a story on the weather balloon shop instead. Distracted by my conversation, the second I looked up Omar was nowhere to be found. Discouraged, I contemplated throwing in the towel on my hunt.
At this point, I knew a few things. The first was that rocket-launching experts don’t like to talk about button pushers. The second was that if you are a button pusher, you don’t talk about it.
Some hours later, rather serendipitously, I ran into Omar. He told me there isn’t a button pusher. Before running off, he said could send me the information on the last person to start the sequence, but that he couldn’t do it right then.
Just as I was losing hope, NASA Kennedy’s Director of Launch Program Services Amanda Mitskevich asked me if a public affairs officer had gotten in touch with me.
Cue: harp and jubilant choir.
Shortly thereafter things started to turn around, Jessica Rye, a ULA public affairs officer, said she might be able to help me. She said the button pusher goes by Larry, and that she’ll see if I can talk to him.
Later on Dave Jarrett, NASA’s LDCM program executive, showed me an e-mail exchange. It said Omar gives the go to the launch director, and he gives the go to Larry. Word of my search must have gotten out.
In said exchange, Chuck Dovale, deputy director of Kennedy’s launch services program, said it was Larry Crass, the launch conductor.
Sat. Feb. 9, 2013. Two Days Before Launch, Vandenberg Air Force Base
Technically, LDCM Project Manager Ken Schwer said that there isn’t a button. He said nobody pushes the button—a computer system runs the launch sequence and there’s a chart that shows how everything works. I ask him to send it to me to help out my search (see above).
I have to say that the entire team does a tremendous job of keeping track of all of the positions and their roles. Looking at this doesn’t clarify anything for me though.
Confused by Ken’s chart, I decided that taking a break from the newsroom and getting a group picture with the team in front of the rocket would be a good diversion (see photo below).
Seeing the rocket up close was incredible. Taking in the enormity of it—and of the size of the group surrounding me—made me realize how special this moment was and how lucky I was to be here.
Just as we all broke up from a group picture, Jim Nelson, the LDCM ground system manager at USGS, tells me that Larry was here. After bolting through the crowd of people with Jim in tow, he pointed me to the right person. Looking like I found my long-lost brother, I finally managed to meet him.
Larry told me there isn’t really a button. However, he and Don Malin, the launch director, granted me an interview. Like many other launch guys, Larry likes to wear the same tie on launch day, but aside from that he relies on hard work and a strong team to ensure a successful launch. This is his second launch as launch conductor. Before that, he’d been training on several missions.
Here’s how my conversation with Larry went:
“I hear you’re the man who gets to push the button?”
“That’s right, in Atlas terms it’s pull the button. It’s pull the button to enable the count. Push the button to stop the count.”
“How did you get to do this?”
“That’s the role of the launch conductor.”
“How do you know when to pull the lever?”
“It’s in the countdown script. It’s scripted when we get into T-4 minute hold. There’s a ten minute hold and a series of steps that we go through when preparing for launch, to enable the launch is one of those steps.”
“Have you been practicing your lever pulling?”
“Of course, we practice during dress rehearsals, and we also do that during our wet dress rehearsals. We’ve done this on previous launches.”
I asked Larry if he ever gets nervous, but he told me they’re well prepared. He’s learned from his bosses who were all previous launch conductors and have trained for years. “It’s practice and part of the professionalism with focusing on the details of making sure the rocket can launch and if you focus on that intently you don’t get nervous,” he said.
“And are you one of those people in the elevators who likes to push the button?”
“No, I ask other people to push the button on the elevator.”
Launch Director Don Malin said this is his third Atlas mission; he’s done six Delta 4’s and 27 Delta 2’s. He told me that its his job is to make sure that the entire countdown is conducted properly. Ultimately, Malin gives permission to launch. He’s confident because the group practices by going through a series of dress rehearsals to make sure they’re ready.
“What’s the most interesting thing about this job?”
“I think what’s interesting are all the different aspects of the operation that have to come together at very specific times and milestones. Without that, we can’t proceed.”
“You don’t have any special regimen, like you have to wear a certain pair of socks?”
“No, the only one I have is to make sure that I do wear socks.”
Alas, there is no button, rather a well-oiled team—making sure the right steps are completed so that the real button pusher (the guy who stops everything in case of emergency) doesn’t have to lift a finger.
There was some competition for the best spots along the fence. I ended up near the pool next to Camilla keeper’s and Esten Hurtle, a software developer who works for Twitter. When we were chatting, he mentioned he had been on the road from San Francisco to Lompoc for two days—on a Vespa. I found that intriguing. Before I knew it, I was doing a full Q & A.
Photo Credit: NASA/Voiland
How did you end find out about this?
Actually John Yembrick (NASA HQ social media guru) came to Twitter and let us know a NASA Social was happening at the Landsat launch. I thought it sounded awesome, and I registered as fast as I possibly could. I was lucky enough to be one of 80 people who got a spot.
How has the social been? What have you been doing?
I went to Vandenberg Air Force Base yesterday. We had an amazing tour. We had a televised Q & A in the morning with many of the people who literally worked on the mission for years to make this happen. It was incredible.
Photo Credit: NASA/Voiland
After that we went on a tour around the base. There was a heritage museum where they showed us all sorts of old launch equipment. There was stuff from Titan II, lots of old switches and dials. They even had a cold war missile on display. It was the forerunner to today’s Delta rockets, which are used for space launches. They had it open, and they were showing us the different stages.
Then we went to the launch pad and met up with Charlie Bolden there because, well, you know, that’s just what you do when you’re at a NASA launch.
You talked to him?
Yeah, he’s seemed like an incredibly nice guy. He gave a little speech about things going on at NASA. NASA apparently just received an award for being the best place in the government to work, and he seemed pretty happy about that. I went up to him after his talk, shook his hand, and told him that a few of my friends work at NASA Ames on some of the supporting software for SLS, the space launch system.
What was the most surprising thing you saw during the social?
The scale of the rocket. The Atlas V is a medium-sized rocket. It’s not like a Saturn V or anything like SLS will be, but still it’s just impressively huge. You see photos of it online, and you’re reading about it, and you think, yeah, ok, this is going to space. But when you’re up there and you’re seeing it all in person, it’s a completely different experience. It was just amazing.
Have you gotten interested in Landsat science or are you mainly interested in the engineering side of things?
Actually, when I was just a tiny kid—I must have been just 5 or 6—my dad had a book of Landsat photos that we used to look at a lot. I remember all the infrared images. They were false color, so they were really eye-popping and gorgeous. As a kid, it was like looking at an alien landscape. They’re just so beautiful.