Tag Archives: gps

On Assignment for Time and Navigation

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What’s missing when you sit in front of a computer all day? Adventure! Luckily, three
Time and Navigation photography missions took me across the country last year, giving me the chance to escape the office.

My first destination was Beer Bottle Pass in the Mojave Desert. This is where Stanley, the autonomous car, navigated its way to victory during the 2005 Defense Advanced Research Projects Agency (DARPA) Grand Challenge race. I needed a photo of the pass to cover the 27-­foot wall behind Stanley in the Time and Navigation gallery. I was confident about this trip until I discovered how precarious this pass could be. The fact that Stanley was able to navigate these sheer drop-­offs and steep inclines is remarkable.

Ashley Hornish

Ashley Hornish in the Mojave Desert

After studying Google Earth for several weeks, my husband, Cory, and I were ready to go. We drove our rented Jeep Wrangler to our starting point outside Primm, Nevada. This area had received a record rainfall the previous week so we had to negotiate washed-out areas and large stones. It took us 45 minutes to travel the seven miles to the pass.

Such a large mural requires more than just one photo; I needed a series that I could stitch together into a panorama. As we gradually moved into the pass, I looked for the best composition. Unfortunately, the road conditions got worse as we progressed, so we never made it to the most treacherous areas (fine with me!). Nevertheless, the trip was a success, and I was relieved to make a safe return to Primm.

Ashley Hornish

Ashley Hornish in the Time and Navigation exhibition. Behind her are Stanley and the mural she photographed in the Mojave Desert.

Since Cory and I were “in the neighborhood,” we arranged a visit to the Goldstone Deep Space Network complex. Located about 35 miles north of Barstow on the Ft. Irwin Military Base, the NASA Deep Space Network is an international network of antennas that supports interplanetary missions and radio and radar astronomy observations for exploring the universe.

I wanted to photograph an old hydrogen maser at the Mars 70­-meter antenna. Now a backup, this maser was the primary frequency standard for the racks of Goldstone timing equipment we have on display in Time and Navigation.

Now used as a backup, this hydrogen maser frequency standard was the primary frequency reference for the Goldstone timing equipment on display in the Time and Navigation exhibition.

Visiting Goldstone is no simple task. Hidden away in the middle of the desert, Goldstone is a 45-minute drive from the nearest highway. Disconcerting signs warned of tank crossings and live ammunition areas. After a safety briefing (don’t touch the snakes and don’t drink the water), our guides escorted us to the timing vault of the massive 70-­meter antenna. The best part about the old maser is that it has a small hole at the top that allowed us to view the purple plasma glowing inside the equipment. After a few quick photos, we were allowed to take a brief look into the control room for the Curiosity rover.

I found myself in a very different landscape for my third trip: the middle of a cornfield in Rippey, Iowa. I needed photos of farmer Roy Bardole harvesting his crops using equipment guided by GPS. Museum photographer Dane Penland agreed to accompany me on this adventure, and we headed to the drought­-stricken area hoping there would actually be crops to photograph.

Roy Bardole

Dane Penland photographs farmer Roy Bardole in a harvester near Rippey, Iowa.

Dane and I ended up spending an entire day in the field with Roy and his two sons as they methodically worked their way through the stalks. We took turns riding inside the combine, watching as the enormous machine drove itself down the lengthy rows without wavering. Farming is much more involved than you might imagine, and I was impressed by the Bardoles’ business sense.

Overall this trip was a success: the weather held, the Bardoles’ yield was better than expected, and the motel wasn’t as bad as I thought it might be. I even got a special sendoff at the Des Moines airport, home to the Des Moines Air National Guard. As my airplane taxied to the runway, we passed several F­-16s that were awaiting takeoff. As we passed, the pilots waved to us. It was a great way to end my adventure.

Ashley Hornish is a graphic designer in the National Air and Space Museum’s Exhibits Department.

Shiny Delivery this Holiday Season for the Time and Navigation Exhibition

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NTS-2

NTS-2 Satellite

Preparation of the upcoming Time and Navigation exhibition is in full swing, and objects are being installed in cases throughout the gallery.  In fact, the gallery became a little more shiny just in time for the holiday season thanks to a delivery from our friends at the Naval Research Laboratory. The object they contributed is a restored engineering model of the NTS-2 satellite. Now, you may be asking, “What is an NTS-2 satellite, besides a shiny box?”  Well, the NTS-2 satellite led a revolution in navigation technology, and can be considered the grandfather of all the satellites which currently help you find your way around town.

The NTS-2 satellite is the descendent of a naval research program known as TIMATION (TIMe/navigATION). The program began in the early 1960s, and tested the possibility of launching highly accurate clocks into space within satellites. The clocks on board the NTS-2 satellite worked by measuring the “tick” of cesium atoms. The cesium atoms vibrated more than nine billion times per second, acting like a super accurate clock. These clocks could then broadcast that time from space, and people on Earth could receive these signals to help them locate themselves on the planet. In 1973, the TIMATION program was combined with other military programs to form the NAVSTAR Global Positioning System (GPS). After successfully launching the NTS-1 satellite in the summer of 1974, NTS-2 was launched on June 23, 1977, forever changing how we navigate on Earth. The two satellites demonstrated the feasibility of using super accurate atomic clocks aboard satellites, and became the basis of the GPS network that your smartphone may use on a daily basis.

The restored engineering model looks very much like the one that went into space on that historic day in 1977. The Naval Research Laboratory did a great job restoring it and installing it in the gallery. We hope you will come and visit it when the exhibition opens in March of 2013!

Tom Paone is a museum specialist in the Aeronautics Division of the National Air and Space Museum.

Stanley Moves In

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On October 24, Stanley, winner of a historic robot race, left its home at the National Museum of American History aboard a flatbed truck and arrived safely at its destination, just seven blocks away. For the foreseeable future, Stanley will be here at the National Air and Space Museum, a centerpiece in the exhibition Time and Navigation:  The Untold Story of Getting From Here to There.

The irony of the situation escaped no one.  Stanley, a driverless vehicle that had navigated 132 miles on its own to win the 2005 Defense Advanced Research Projects Grand Challenge, needed the help of scores of people AND a truck ride to get from there to here.

Stanley

Stanley hitches a ride to the National Air and Space Museum. Photo by Richard Strauss

Frankly, moving Stanley is nerve-racking for me. I collected Stanley for the American History Museum’s robot collection.  I feel responsible for Stanley’s safety and the safety of everyone involved with wrangling such a big, heavy car.  On moving day, it turned out, there really was no cause for worry. Everybody—American History’s experienced vehicle mover Shari Stout, the skilled riggers from Ely, and the welcoming Air and Space staffers—everybody knew exactly what to do to put Stanley in just the right spot for long-term display.

Now that Stanley is securely in place, though, there’s a moment to reflect.  It’s worth thinking more deeply about the car’s place in Time and Navigation and the reasons for collecting contemporary objects for the Smithsonian in the first place.

Some have already wondered:  what’s a car doing in the National Air and Space Museum?  In Time and Navigation, we link Stanley directly to satellite navigation, a subject clearly within the Museum’s scope.  The car’s ability to drive itself is a new application for satellite navigation, made possible when computers combine GPS (global positioning system) coordinates with other kinds of data to construct an image of the road ahead, complete with obstacles.  And there’s another connection:  Stanley operates on the ground in much the same way that UAVs, that’s Unmanned Aerial Vehicles, operate in the air.  Stanley moved into the Museum right under the UAV exhibition on the west end.

stanley

Stanley moves into the National Air and Space Museum. Photo by Mark Avino

When Stanley won the off-road DARPA race in 2005, the achievement was a giant technical step forward for autonomous vehicles, the vehicles like Stanley that drive themselves.   Now, seven short years later, numerous carmakers and Google are testing self-driving cars.  Three states—Nevada, Florida, and California—have passed legislation permitting them on state roads.  Advocates foresee a future where such cars will relieve congestion on highways, reduce traffic accidents, and provide transportation for those who otherwise cannot or do not want to drive.  No point going to the showroom to shop for your robot car just yet, but insiders predict the technology will be commercially available soon.

License Plate

Nevada license plate issued for testing autonomous vehicles on the state’s public roads. Photo by Wayne Wakefield.

Predicting the future, like moving Stanley, makes me nervous. My training and interests make me passionate about the past. I’m a historian and a curator, not a soothsayer. Making decisions about what to collect from the long-ago past, a curator stands on pretty solid ground. Often there’s a body of existing research and documentation that verifies the importance of an object from long ago. That’s collecting from inside a comfort zone.

But collecting contemporary objects like Stanley comes close to predicting the future.  It’s a risky business.  Curators have to make educated guesses that today’s technical innovation will be tomorrow’s historic milestone.  Curators who do contemporary collecting take the risk that an object making headlines today will remain representative of some important event or illustrative of how Americans absorbs new technologies.  Such an object might even carry material evidence that inspires our successors to dig deeper into research we haven’t even imagined yet.  Or maybe collecting such an object won’t have any of those useful outcomes.  Maybe it will simply lie fallow forever after in storage.  As I say, it’s a risky business.

An important indicator of an object’s historical worth is whether it yields rich  insights.  So far Stanley does not disappoint.  On display at the National Museum of American History, Stanley represented the latest in a long line of wheeled robots, a history that can be traced back to renaissance automatons.  At the Air and Space Museum, Stanley’s technologies let us see inside the “black box” of navigation and consider emerging technologies that are likely to change the ways we get from here to there.  Whether there will be more insights down the road, we’ll just have to wait and see.

Carlene Stephens is a curator at the National Museum of American History in Washington, DC. She is currently working with a team of curators, designers and restoration specialists at the National Air and Space Museum to develop the Time and Navigation exhibition.

For more about Stanley’s recent move, see the Smithsonian blog.

 

What Can You Really See From Space?

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Most people know that satellites in orbit do useful things such as collect images of the Earth’s surface. At the National Air and Space Museum I use satellite images in my job to understand changes in the Earth’s land surface. Today millions of people are acquainted with satellite imagery on internet map services. People sometimes ask me if it’s possible to see even more detail from space. In this post I’ll explore what is really visible in different types of satellite data.

There are dozens of orbiting remote sensing satellites, and the level of detail they see depends on its precise mission. “Remote sensing” just means looking at something from a distance. In this case we’re talking about viewing the Earth from at least hundreds of miles above the atmosphere.

The images on internet map servers are provided by a recent generation of satellites that collect detailed images, including the GeoEye and WorldView satellites. Objects smaller than automobiles are visible in some of these images. In the past, only military and reconnaissance satellite were capable of this kind of detail.

IKONOS

Image from the IKONOS satellite showing downtown San Francisco. This type of image shows great detail over small areas.

Other satellites observe large areas and discern things the size of agricultural fields. These spacecraft, including the Landsat satellites, are useful for mapping cities or regional changes in land cover.

Landsat 7

Image from the Landsat 7 showing the metropolitan area of Mexico City in the upper left. On the right is the volcano Popocatepetl, which appears dark red in this false color infrared image. This image covers an area about 100 miles across.

Another class of satellites orbit thousands of miles out in space. These spacecraft, including the GOES satellites, are designed to observe changing weather over an entire hemisphere of the Earth. They cannot discern small details.

GOES

View from GOES satellite showing weather systems moving across the entire globe.

In the past, it was often incorrectly stated that the Great Wall of China was the only man-made thing visible from space. Although an astronaut would probably not be able to see it with unaided eyes, the Great Wall is visible using orbiting sensors. However, plenty of other things made by humans are also visible. It was sometimes even stated that the Great Wall is visible from the Moon, but that’s definitely not possible. If you stood on the Moon, the entire Earth would appear to be about the size of a quarter held at arm’s length.

In some Hollywood films, satellites provide moving images from space. The hero immediately targets a satellite to search for evildoers. While this type of real-time imagery looks very cool, it’s not really how satellites work. Orbiting satellites pass over a particular point only every couple of weeks, and they cannot be immediately moved or collect moving images.

There is a way to get imagery like that, but it’s from unmanned airplanes. Drone aircraft can provide real-time imagery and even be equipped with weapons to attack targets.

In reality, satellite imagery is used for “before” and “after” images. These can be used for research purposes and for responses to emergencies. Recently media outlets widely used imagery from the GeoEye-1 satellite to show tsunami devastation in Japan.

Sometimes a satellite passes overhead at just the right time to capture a rapid change. The Indian Ocean tsunami on December 26, 2004 was one of those times. The QuickBird satellite just happened to pass over Sri Lanka when the wave of water crashed ashore, providing an amazing (and scary) image. In 2005 the same satellite provided images of New Orleans immediately after Hurricane Katrina. I had an opportunity to closely examine those images at the time, and I remember making a sobering calculation of how much of the city remained submerged.

So the detail visible in a satellite image all depends on the mission of each satellite and the scale of its observations. A few non-military satellites can see objects down to about half the size of a car. Some military satellites can still see even smaller things. But that does not tell us the whole story. For most applications we need to see larger areas, which requires other satellites that observe at a different scale.

For each satellite imaging project, we need to choose between seeing small details or seeing a large area. You can’t usually have both. But  increased computing power has made it possible to combine highly detailed images to cover very large areas. The seemless imagery on internet map servers actually consists of many thousands of individual images that have been combined. Scientists use the same kind of approach to view fine scale vegetation changes across continents. Methods of combining small images will continue to be valuable for making detailed observations of the Earth in the future.

Andrew K. Johnston is a geographer in the Center for Earth and Planetary Studies at the National Air and Space Museum.