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A Group of Suitcase-Sized Satellites Will Transform Hurricane Tracking

Screenshot from "CYGNSS Overview," NASA Langley Research Center

Earlier this month, NASA launched a constellation of small satellites that will transform hurricane forecasting and enable new insights into storm formation and activity. Called the Cyclone Global Navigation Satellite System (CYGNSS), eight spacecraft, each the size of a carry-on suitcase, are flying over the tropics to measure and map ocean winds. Because of their altitude, heavy rain and storm surges are no obstacles to the satellites, and when hurricanes form, the spacecraft will be able to peer through walls of water into the storm’s core and continue to collect data—something no space-based system has ever done before.

“CYGNSS is a tool that will provide us 24/7 coverage of the tropical cyclone zone. It will improve our knowledge of how hurricanes grow so that we can better prepare and protect people in the path of each hurricane as it comes,” Christine Bonniksen, CYGNSS program executive with the Science Mission Directorate's Earth Science Division at NASA Headquarters, tells mental_floss.

THE RAIN BARRIER HAS BLOCKED OUR VIEW

Over the past several decades, there has been a steady improvement in storm track forecasting—or where storms will hit—and the National Hurricane Center’s error rate is half of what it was 20 years ago. The same cannot be said for storm intensity forecasting—how strong these storms will be. “If you look at the record for their intensity forecast, there has been very, very little improvement in the last 20 years,” said Chris Ruf, the principal investigator on the CYGNSS mission and a scientist at the University of Michigan, Ann Arbor. One of the primary reasons for this is that today’s satellites are unable to measure what’s going on in the inner core of hurricanes. “This has been identified for many years as a primary lacking ingredient in the numerical forecasts that are used by the National Hurricane Center. They wish they had information on the inner core of the storms and they don’t.”

Storm cores have so far been impenetrable because current wind-observing spacecraft cannot see through rain. This is because their on-board instruments emit signals at an 8-millimeter wavelength—about the same size as a large raindrop. When the signals encounter rain, they are simply scattered and absorbed. (Hurricane paths depend on environmental factors outside of the storm, which is why this rain shroud has not been an impediment to predicting where storms will hit.)

Additionally, it takes about three days for current systems to collect data to build a map of global wind speeds and precipitation. This is a big problem if you’re trying to track the rapid intensification of tropical storms and hurricanes, which can happen in a matter of hours. So until now, scientists have had to rely on so-called “Hurricane Hunter” aircraft to fly into the storm to perform wind speed reconnaissance.

THE CYGNSS SOLUTION

CYGNSS changes all of this by using GPS satellite signals, which were designed to penetrate heavy rains. GPS operates at a 19-centimeter wavelength—more than long enough to avoid rain interaction. When GPS satellite signals hit the ocean, they reflect back into space and are received by CYGNSS observatories. Think about the way the Moon reflects on a placid lake: When the lake is calm, the Moon's image is sharp. When the wind blows, the water roughens and the image diffuses. CYGNSS relies on a similar principle, reading the clarity of the GPS signals to reveal the characteristics of the wind. It measures the strength of the GPS signal as it scatters off the ocean surface to determine wind speed.

The eight CYGNSS observatory spacecraft operate evenly in a single orbital plane around the Earth. Each satellite has a payload called a Delay Doppler Mapping Instrument, a GPS receiver capable of tracking four different GPS signals simultaneously. Two antennas look down at reflected GPS signal and take measurements of the diffuse scattering, and from those derive the wind speed and activity. Meanwhile, one antenna looks up and receives a direct GPS satellite signal for geolocation. In essence, each 65-pound satellite is doing the work of four Hurricane Hunter airplanes. Collectively, CYGNSS is like a squadron of 32 such planes flying continuously over the tropics taking simultaneous measurements.

The system gives a total refresh of the entire tropical wind distribution map every seven hours, even under heavy precipitation. In a hurricane or tropical storm—including in areas with the highest wind speeds and the most powerful surges—CYGNSS can immediately answer questions about the storm size, intensity, and the reach of its strong winds. Moreover, because the satellite constellation has such expansive coverage of the Earth, it can collect massive amounts of data on the entire storm environment. There are three different data downlink points around the world, and the data can be downloaded from the satellites within the hour—an unprecedented timeframe.

HOW THE LAUNCH WENT DOWN

CYGNSS launched on the morning of December 15, 2016 from Cape Canaveral with the help of a Pegasus rocket, an air launch system. The rocket was mounted to the bottom of an L-1011 airplane called Stargazer that took off from a runway, just like any other plane you’ve ever seen. At 39,000 feet above the Atlantic Ocean, the plane released the Pegasus rocket, which ignited five seconds later and powered its way into space. The fairings hatched away and the deployment vehicle separated, and the eight small satellites released themselves in pairs over 30-second intervals. Ten minutes after separation, their solar arrays deployed. They then moved into position in orbit and began operation.

By 4:12 pm ET that same day, the CYGNSS team had successfully made contact with all eight satellites. "It is an amazingly rewarding feeling to spend such an intense and focused time working on CYGNSS and then, in a matter of just a few hours, have the entire constellation suddenly come to life," Ruf said in a brief mission update. "I am excited (and a little exhausted) and really looking forward to diving into the engineering data in the coming days, and then into the science data in the weeks to follow."

This is NASA’s flagship Earth Venture–class mission, which is a new NASA program designed for low-cost, high-technology suborbital (think aircraft and balloons) and orbital (CYGNSS) projects. Two previous missions of this class were aircraft designed for atmospheric research and communications. This is the first spaceborne Earth Venture endeavor. Southwest Research Institute in Boulder, Colorado runs CYGNSS mission operations, and science operations are run from the University of Michigan. The primary $160 million mission will run for two years—enough time to fill in blank spots in the hurricane dataset, get a grip on how storm cores intensify, and hopefully refine the forecast models that lives depend on.  

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Kevin Gill, Flickr // CC BY-2.0
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Space
10 Facts About the Dwarf Planet Haumea
Kevin Gill, Flickr // CC BY-2.0
Kevin Gill, Flickr // CC BY-2.0

In terms of sheer weirdness, few objects in the solar system can compete with the dwarf planet Haumea. It has a strange shape, unusual brightness, two moons, and a wild rotation. Its unique features, however, can tell astronomers a lot about the formation of the solar system and the chaotic early years that characterized it. Here are a few things you need to know about Haumea, the tiny world beyond Neptune.

1. THREE HAUMEAS COULD FIT SIDE BY SIDE IN EARTH.

Haumea is a trans-Neptunian object; its orbit, in other words, is beyond that of the farthest ice giant in the solar system. Its discovery was reported to the International Astronomical Union in 2005, and its status as a dwarf planet—the fifth, after Ceres, Eris, Makemake, and Pluto—was made official three years later. Dwarf planets have the mass of a planet and have achieved hydrostatic equilibrium (i.e., they're round), but have not "cleared their neighborhoods" (meaning their gravity is not dominant in their orbit). Haumea is notable for the large amount of water ice on its surface, and for its size: Only Pluto and Eris are larger in the trans-Neptunian region, and Pluto only slightly, with a 1475-mile diameter versus Haumea's 1442-mile diameter. That means three Haumeas could fit sit by side in Earth—and yet it only has 1/1400th of the mass of our planet.

2. HAUMEA'S DISCOVERY WAS CONTROVERSIAL.

There is some disagreement over who discovered Haumea. A team of astronomers at the Sierra Nevada Observatory in Spain first reported its discovery to the Minor Planet Center of the International Astronomical Union on July 27, 2005. A team led by Mike Brown from the Palomar Observatory in California had discovered the object earlier, but had not reported their results, waiting to develop the science and present it at a conference. They later discovered that their files had been accessed by the Spanish team the night before the announcement was made. The Spanish team says that, yes, they did run across those files, having found them in a Google search before making their report to the Minor Planet Center, but that it was happenstance—the result of due diligence to make sure the object had never been reported. In the end, the IAU gave credit for the discovery to the Spanish team—but used the name proposed by the Caltech team.

3. IT'S NAMED FOR A HAWAIIAN GODDESS.

In Hawaiian mythology, Haumea is the goddess of fertility and childbirth. The name was proposed by the astronomers at Caltech to honor the place where Haumea's moon was discovered: the Keck Observatory on Mauna Kea, Hawaii. Its moons—Hi'iaka and Namaka—are named for two of Haumea's children.

4. HAUMEA HAS RINGS—AND THAT'S STRANGE.

Haumea is the farthest known object in the solar system to possess a ring system. This discovery was recently published in the journal Nature. But why does it have rings? And how? "It is not entirely clear to us yet," says lead author Jose-Luis Ortiz, a researcher at the Institute of Astrophysics of Andalusia and leader of the Spanish team of astronomers who discovered Haumea.

5. HAUMEA'S SURFACE IS EXTREMELY BRIGHT.

In addition to being extremely fast, oddly shaped, and ringed, Haumea is very bright. This brightness is a result of the dwarf planet's composition. On the inside, it's rocky. On the outside, it is covered by a thin film of crystalline water ice [PDF]—the same kind of ice that's in your freezer. That gives Haumea a high albedo, or reflectiveness. It's about as bright as a snow-covered frozen lake on a sunny day.

6. HAUMEA HAS ONE OF THE SHORTEST DAYS IN THE ENTIRE SOLAR SYSTEM.

If you lived to be a year old on Haumea, you would be 284 years old back on Earth. And if you think a Haumean year is unusual, that's nothing next to the length of a Haumean day. It takes 3.9 hours for Haumea to make a full rotation, which means it has by far the fastest spin, and thus shortest day, of any object in the solar system larger than 62 miles.

7. HAUMEA'S HIGH SPEED SQUISHES IT INTO A SHAPE LIKE A RUGBY BALL.

haumea rotation gif
Stephanie Hoover, Wikipedia // Public Domain

As a result of this tornadic rotation, Haumea has an odd shape; its speed compresses it so much that rather than taking a spherical, soccer ball shape, it is flattened and elongated into looking something like a rugby ball.

8. HIGH-SPEED COLLISIONS MAY EXPLAIN HAUMEA'S TWO MOONS.

Ortiz says there are several mechanisms that can have led to rings around the dwarf planet: "One of our favorite scenarios has to do with collisions on Haumea, which can release material from the surface and send it to orbit." Part of the material that remains closer to Haumea can form a ring, and material further away can help form moons. "Because Haumea spins so quickly," Ortiz adds, "it is also possible that material is shed from the surface due to the centrifugal force, or maybe small collisions can trigger ejections of mass. This can also give rise to a ring and moons."

9. ONE MOON HAS WATER ICE—JUST LIKE HAUMEA.

Ortiz says that while the rings haven't transformed scientists' understanding of Haumea, they have clarified the orbit of its largest moon, Hi'iaka—it is equatorial, meaning it circles around Haumea's equator. Hi'iaka is notable for the crystalline water ice on its surface, similar to that on its parent body.

10. TRYING TO SEE HAUMEA FROM EARTH IS LIKE TRYING TO LOOK AT A COIN MORE THAN 100 MILES AWAY.

It's not easy to study Haumea. The dwarf planet, and other objects at that distance from the Sun, are indiscernible to all but the largest telescopes. One technique used by astronomers to study such objects is called "stellar occultation," in which the object is observed as it crosses in front of a star, causing the star to temporarily dim. (This is how exoplanets—those planets orbiting other stars—are also often located and studied.) This technique doesn't always work for objects beyond the orbit of Neptune, however; astronomers must know the objects' orbits and the position of the would-be eclipsed stars to astounding levels of accuracy, which is not always the case. Moreover, Ortiz says, their sizes are oftentimes very small, "comparable to the size of a small coin viewed at a distance of a couple hundred kilometers."

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NASA/JPL
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Space
The Secret Cold War History of the Missile That Launched America's First Satellite
NASA/JPL
NASA/JPL

In 1950, a group of scientists proposed the International Geophysical Year (IGY), a sort of "Science Olympics" in which nations of the world would embark on ambitious experiments and share results openly and in the spirit of friendship. The IGY, they decided, would be celebrated in 1957.

As part of the IGY, the Soviet Union vowed that it would launch an artificial satellite for space science. The U.S., not to be left behind, said that it, too, would launch a satellite. Both countries had ulterior motives, of course; the ostensibly friendly rivalry in the name of science allowed the two superpowers, already engaged in the Cold War, to quite openly develop and test long-range ballistic missiles under the guise of "friendship."

The Soviet Union aimed to develop missiles capable of reaching both western Europe and the continental United States. Such "intercontinental ballistic missiles," a.k.a. ICBMs, would, Nikita Khrushchev hoped, neutralize the overwhelming nuclear superiority of America, which had a $1 billion squadron of B-52 bombers. Their development would solve another of the Soviet Union's pressing issues: Military expenditures were gobbling up one-fifth of the economy, while agricultural output was in a severe decline. In short, there were too many bullets being produced, and not enough bread. Long-range rockets armed with nuclear weapons, already in the Soviet arsenal, could allow Khrushchev to slash the size and expense of the Red Army, forego a heavy long-range bomber fleet, and solve the food problems plaguing the country.

Meanwhile, in the United States, an Army major general named John Bruce Medaris saw a big opportunity in the International Geophysical Year: to use a missile designed for war—which the Army had been prohibited from developing further—to launch a satellite into space. But Medaris, who commanded the Army Ballistic Missile Agency in Huntsville, Alabama, would need to be creative about selling it to the Department of Defense.

AN EDICT: NO ROCKETS OVER 200 MILES

Medaris was working under heavy restrictions against stiff competition. In 1956, the Secretary of Defense, Charlie Erwin Wilson, had issued an edict expressly forbidding the Army from even planning to build, let alone employ, long-range missiles "or for any other missiles with ranges beyond 200 miles." Land-based intermediate- and long-range ballistic missiles were now to be the sole responsibility of the Air Force, while the Navy had authority for the sea-launched variety.

The idea was to avoid program redundancy and free up money to pay for the B-52 fleet, but the edict wound up having a catastrophic effect on the American missile program and its space ambitions, as author Matthew Brzezinski recounts in Red Moon Rising: Sputnik and the Hidden Rivalries That Ignited the Space Age.

At the time of Wilson's injunction, the Army's rocketry program was far ahead of the Air Force's or Navy's. The Army had just tested a rocket prototype called Jupiter that flew 3000 miles—but it was the new and flourishing Air Force that had the political backing of Washington. Moreover, few in the capital were worried about the Soviets developing long-range missile capability. Yes, they were trying, but they didn't have a prayer at developing one before the technically advanced United States, and in the meantime, the U.S. had overwhelming nuclear bomber superiority. When you got right down to it—the DOD reasoning went—who cared whether the Army, Air Force, or Navy developed our missiles?

Major General Medaris cared. He believed that, thanks to a German aerospace engineer named Wernher von Braun, the Army Ballistic Missile Agency had made too much progress on ballistic missile technology to just stop working on them now.

In the aftermath of World War II, the United States—and the Soviets—had scrambled to gather German missile technology. The U.S. lacked the ability to develop anything as powerful as Germany's lethal V-2 rocket and desperately wanted not only as much V-2 hardware as it could find but the V-2 designer himself, von Braun.

The U.S. succeeded in recruiting the engineer, ultimately assigning him to the Army's missile agency in 1950. There Von Braun and his team developed and deployed the Redstone, a short-range missile that could travel 200 miles. (This is where Wilson's 200-mile limitation came from.) Von Braun also began work on a research rocket (in parlance, a sounding rocket) based on the Redstone that could fly 1200 miles. It was not, technically, a missile—it wasn't designed to carry deadly ordnance. Its purpose was to test thermal nose-cone shields. This rocket was called the Jupiter C.

The 1956 injunction on Army missile development threatened the tremendous progress the Army had made. Both Medaris, who led the Army's missile program, and von Braun, who had now spent years trying to advance the rocket technology of the United States, were infuriated.

ARMY VS. NAVY (VS. THE SOVIETS)

With the IGY deadline looming, Medaris saw an opportunity to save the Army's role in rocket design. He had the genius German engineer and all the hardware necessary to do the job.

Medaris began to wage bitter bureaucratic warfare to protect the Army's missile program. The Air Force's program, he pointed out to defense officials, seemed not to be going anywhere—there was simply not much rush to replace bomber pilots with long-range missiles in a pilot-led organization. Worse yet, the Naval Research Laboratory, which had been given charge of the U.S. satellite entry for the IGY, was hopelessly behind schedule and underfunded. The Navy's Vanguard program, as it was called, would never succeed in its goal on time. (Why, then, did the Navy get the coveted assignment? In large measure because the Naval Research Laboratory was an essentially civilian organization, which just seemed more in the spirit of the International Geophysical Year.)

design plan of explorer 1 satellite
NASA/Marshall Space Flight Center Collection

Through all of this, it never occurred to Medaris that he was actually in a Space Race against the Soviet Union. To his mind, he was competing against the other branches of the U.S. military. To keep his missile program alive while he waged war in Washington, he allowed von Braun to continue work on ablative nose cone research using the Jupiter C research rocket. Not missile—Medaris could not emphasize that point enough to the Department of Defense. It was a research rocket, he stressed, and therefore exempt from the ban on Army missile development.

Medaris argued to Secretary Wilson that if they just gave the Jupiter C a fourth stage—that is, basically, a rocket on top of the rocket—it could reach orbital velocity of 18,000 miles per hour and get a satellite up there.

All of his arguments fell on deaf ears. "Not only were Medaris's pleas gruffly rebuffed," writes Brzezinski, but Wilson "spitefully ordered the general to personally inspect every Jupiter C launch to make sure the uppermost stage was a dud so that Von Braun did not launch a satellite 'by accident.'"

So instead, Medaris made sure that Jupiter C "nose-cone research" plunged ahead. It simulated everything about a long-range, satellite-capable ballistic missile, but it was not a missile. The Jupiter C kept the Army in the rocket development business. Just in case something went south with the Navy's Vanguard program, however, Medaris had two Jupiter C rockets put into storage. Just in case.

AND THEN CAME SPUTNIK

Two events would happen in 1957, the International Geophysical Year, that changed the trajectory of history. First: Secretary Wilson, who so vexed the Army missile program, retired. On October 4, 1957, his replacement, Neil McElroy, soon to be confirmed by the Senate, visited Huntsville to tour the Army Ballistic Missile Agency. Second: Later that same day, the Soviet Union stunned the world by launching Sputnik-1 into orbit and ushering humankind into the Space Age.

Von Braun was apoplectic. He'd devoted his life to rocketry. To be beaten by the Soviets! "For God's sake," he implored McElroy, "cut us loose and let us do something! We have the hardware on the shelf." He asked the incoming secretary for just 60 days to get a rocket ready.

McElroy couldn't make any decisions until he was confirmed, but that didn't faze Medaris, who was so certain that his group would get the go-ahead to launch a satellite that he ordered von Braun to get started on launch preparations.

What Medaris didn't anticipate was the Eisenhower White House's response to Sputnik. Rather than appear reactionary or spooked by the Soviet's sudden access to the skies over the U.S., the President assured the American people that there was a plan already in place, and everything was fine—really. The Navy's Vanguard program would soon launch a satellite as scheduled.

One month later, there was indeed another launch—by the Soviet Union. This time the satellite was a dog named Laika. In response, both Medaris and von Braun threatened to quit. To pacify them, the Defense Department promised that they could indeed launch a satellite in January, after the Vanguard's launch. von Braun, satisfied that he would get his shot, had a prediction to make: "Vanguard," he said, "will never make it."

And he was right. On December 6, 1957, the nation watched from television as the Vanguard launch vehicle began countdown from a virtually unknown expanse of Florida swampland called Cape Canaveral. At liftoff, the rocket rose a few feet—then blew up.

THE SECRET IDENTITY OF MISSILE NO. 29

After the Navy's failure, the Army was back in business. Medaris had his approval. The Jupiter C rocket would be allowed to carry a satellite called Explorer-1 to space.

Unlike the public outreach that accompanied the Vanguard launch, however, Medaris's rocket readying was done in total secrecy. The upper stages of the rocket were kept under canvas shrouds. The rocket was not to be acknowledged by Cape Canaveral personnel as the rocket, but rather, only as a workaday Redstone rocket. In official communications, it was simply called "Missile Number 29."

The Jupiter C destined to carry the spacecraft was one of the rockets placed in storage "just in case" after the Army was locked out of the long-range missile business. On the launch pad, however, it would be called "Juno." (The name change was in part an effort to conceal the rocket's V-2 and military lineage.) Explorer-1 was built by Jet Propulsion Laboratory at the California Institute of Technology. JPL had worked with the Army "just in case" the Navy's Vanguard program failed. ("We bootlegged the whole job," said William Pickering, the then-director of the JPL lab.) The onboard scientific instrument, a Geiger counter developed by James Van Allen of the University of Iowa, had also been designed with the Army's rocket in mind … just in case.

Medaris wanted no publicity for his launch. No VIPs, no press, no distractions. Even the launch day was to be kept secret until the Explorer-1 team could confirm that the satellite had achieved orbit successfully.

And then 60 years ago today, Explorer-1 left Earth from launch pad 26 at the cape. The response is best captured by the breathless headline atop the front page of the New York Times [PDF] the following morning: "ARMY LAUNCHES U.S. SATELLITE INTO ORBIT; PRESIDENT PROMISES WORLD WILL GET DATA; 30-POUND DEVICE IS HURLED UP 2,000 MILES."


NASA/JPL

America's first satellite would go on to circle the Earth 58,000 times over the span of 12 years. The modest science payload was the first ever to go into space, and the discovery of the Van Allen belts—caused by the capture of the solar wind's charged particles by the Earth's magnetic field—established the scientific field of magnetospheric research.

Six months after the spacecraft launched, the U.S. would establish the National Aeronautics and Space Administration, a.k.a. NASA. (For the next three years, however, the Soviet Union would continue to dominate the Space Race, establishing a long run of "firsts," including placing the first human in space.) Wernher von Braun became director of Marshall Space Flight Center in Huntsville and was chief architect of the Saturn V rocket that powered the Moon missions. Jet Propulsion Laboratory has since launched more than 100 spacecraft across the solar system and beyond.

The unsung hero today, of course, is Major General Bruce Medaris, whose tenacity righted the U.S. rocket program. It is impossible to know how the Space Race might have ended without his contributions. We do know how his career ended, though. When at last he retired from the military, he rejected overtures to advise John F. Kennedy on space policy. Instead, he took a job as president of the Lionel Corporation, famed for its toy trains. He eventually set his sights on the heavens, literally, and entered the priesthood. He died in 1990 and is buried in Arlington National Cemetery, his legacy forever set among the stars.

For further reading, see Matthew Brzezinski's Red Moon Rising: Sputnik and the Hidden Rivalries That Ignited the Space Age.

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