After two scrubbed launch attempts, SpaceX's Falcon 9 rocket finally blasted off on Tuesday to send a commercial satellite where no SpaceX payload has gone before: 22,000 miles up, into geostationary orbit.
An orbit that high allows a satellite to be "parked" over a stable point on Earth's surface — which is why it's favored for the kinds of military and telecom satellites that provide the richest market for commercial launch providers.
The 6,918-pound (2,138-kilogram) SES-8 telecommunication satellite was sent up from Cape Canaveral Air Force Station's Launch Complex 40 on Tuesday right on time, at 5:41 p.m. ET. Tuesday's smooth countdown came in contrast to the previous launch attempts, on Nov. 25 and 28, when technical glitches frustrated SpaceX's efforts.
The launch could be a "game changer" for the satellite industry, according to Martin Halliwell, chief technology officer for Luxembourg-based SES. "It's going to really shake the industry to its roots," he told reporters last month.
SES reportedly paid less than $60 million for the launch, which is tens of millions of dollars less than the going rate for satellite launches heading for geostationary orbit.
California-based SpaceX and its two-stage Falcon 9 rocket have already made their mark with a series of successful NASA-funded missions to resupply the International Space Station, which flies at an altitude of about 250 miles (400 kilometers). But early versions of the Falcon 9 weren't powerful enough to put large payloads into geostationary transfer orbit, or GTO. Over the past year, the rocket has been upgraded with Merlin 1D engines and other enhancements, with the aim of widening the market for Falcon launches.
The Falcon 9 v1.1 rocket had its first tryout in September, with the launch of the Canadian Space Agency's Cassiope research satellite. That satellite was deployed successfully, but afterward, the Falcon's second-stage engine failed to reignite in a test to reach higher orbit. Relighting the second stage is essential for the success of geostationary satellite launches.
The problem was traced to a frozen igniter fluid line — an issue that didn't turn up during ground testing under warmer conditions. To fix the problem, the company added insulation to the line.
SpaceX said the second-stage engine restarted as planned after Tuesday's launch. "Orbit looks nominal," the company reported in a Twitter update.
Minutes later, SpaceX announced that the satellite separated from the second stage and was in its proper geostationary transfer orbit, varying in altitude from 183 miles (295 kilometers) to 49,700 miles (80,000 kilometers). That took care of SpaceX's launch responsibility.
SpaceX's billionaire founder, Elon Musk, celebrated the achievement with a tweet: "Restart was good. ... Yes!!"
Over the next couple of weeks, the satellite's thrusters are expected to stabilize the orbit at a steady altitude of 22,000 miles (36,000 kilometers).
The satellite was built for SES by Virginia-based Orbital Sciences Corp. It will broadcast in the Ku-band for South Asia and Indochina, and in the Ka band for the Asia-Pacific region.
SpaceX has a dozen Falcon 9 launches on its manifest for next year, including more geostationary satellites.
More about commercial space ventures:
Blue Origin touts its new rocket engine
NASA outlines final steps in spaceship plan
NBC News archive on SpaceX
Alan Boyle is NBCNews.com's science editor. Connect with the Cosmic Log community by "liking" the log's Facebook page, following @b0yle on Twitter and adding the Cosmic Log page to your Google+ presence. To keep up with Cosmic Log as well as NBCNews.com's other stories about science and space, sign up for the Tech & Science newsletter, delivered to your email in-box every weekday. You can also check out "The Case for Pluto," my book about the controversial dwarf planet and the search for new worlds.
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CAMOUFLAGE
Bold 'razzle dazzle' camouflage fools the eye
Stephanie Pappas LiveScience
3 minutes ago
IMAGE: Locust
Lisa Clancy
Locusts' compound eyes are fooled by motion dazzle camouflage, which uses bold contrasting patterns to confuse the viewer's sense of speed and trajectory.
A controversial, high-contrast camouflage that once decorated the hulls of World War I battleships really exists in nature — though whether humans are fooled remains an open question.
"Motion dazzle" camouflage uses bold geometric patterns in an attempt not to blend in, but to confuse observers. Theoretically, these patterns make it difficult to judge speed and trajectory. Zebras' stripes may be an example of this camouflage, though that's never been proven — their bold black-and-white stripes also repel flies, which may be their main function. Motion dazzle camouflage isn't about blending in, as blend-in camouflage stops working as soon as an animal moves. A similar type of camouflage is disruptive or edge camouflage, which similarly uses bold patterns to confuse the eye even when an animal is in motion.
During World War I, the British and United States Navies adopted dazzle camouflage on their warships, resulting in "razzle-dazzle" vessels that looked like the brainchildren of Picasso. Despite the widespread use, nobody knew for sure whether razzle-dazzle camouflage worked, and computer-based studies on humans have yielded mixed results. [Optical Illusions: A Gallery of Visual Tricks]
"The actual evidence that the phenomenon really exists has been a bit sketchy," said Roger Santer, a zoologist at Aberystwyth University in the United Kingdom.
Tricky camouflage
To figure out whether dazzle camouflage really exists, Santer turned to an organism he knows well: the locust, which is equipped with specialized vision neurons that respond to looming objects. Looming is an important motion to detect if you're a locust, as it could indicate that a predator is headed your way, ready to devour you whole. When a loom-detecting neuron fires, it triggers flying locusts to leap or to swerve out of the way.
Dazzle camouflage should mask motion, so if the camouflage really works, it should keep this neuron from working at its best, Santer reasoned.
To test the idea, they parked locusts in front of specialized computer screens, monitoring their visual neurons with copper wires inserted into their heads. On the screen, locusts would see a series of squares, expanding rapidly so as to look like they were looming toward the insects. Santer varied the contrast of the squares against the background. In some trials, he split the squares into top and bottom halves, which he also varied in contrast.
A dazzling effect
The results showed something counterintuitive. The locusts' neurons responded more weakly to squares with a light bottom half and a dark top half than they did to a black square alone. Adding a light half to a square might seem easier to detect, but apparently not for the locusts. [Vision Quiz: What Can Animals See?]
The reason seems to be a quirk in the locust's visual system, Santer said. When a dark stimulus expands, it sends a "lights off" signal to the visual system, as a dark object replaces the bright background. The result is that the locust senses something coming and gets out of the way.
But when a light stimulus is tacked onto that dark stimulus, the visual system gets two conflicting messages. The expanding dark says "incoming!" but the expanding lightness seems to indicate something retreating.
"It causes these two opposite stimuli on the eye that antagonize one another," Santer told LiveScience.
The confusing, oppositional signals cause the visual neuron to respond more weakly than it otherwise would. The neural activity peaks later and at a lower rate in response to the motion dazzle (the patterned squares), Santer said. This activity correlates with the locust behavior, so it has real-world effects.
Real-world razzle-dazzle
Lots of animals, including mammals, birds and fish, have looming-detection neurons, Santer said, but whether motion dazzle would fool them too is still unknown. The studies on human perception of motion dazzle all focused on sideways motion, not an object coming toward the viewer, he said.
Nevertheless, the study is the first to demonstrate conclusively that motion dazzle works, Santer said. The next step would be to find out if predators have evolved to wear these patterns specifically to fool their prey, and if motion dazzle camouflage really benefits organisms in the real world, he said.
"Insects are really interesting and important models to investigate this with," Santer said. "If we're going to be looking at motion dazzle from the point of view of theoretical predators catching prey, they're massively abundant, so they're important animals for investigating the motion dazzle effect."
Santer's findings are detailed Tuesday (Dec. 3) in the journal Biology Letters.
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