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BU Profs Brace for Storms from Outer Space

Part one: Tracking solar eruptions

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storms-magfield.jpg

After a coronal mass ejection explodes from the surface of the sun, its plasma cloud hits the Earth’s magnetic field, spawning storms that can disrupt communications, damage satellites, and cause power blackouts. Photo courtesy of SOHO (ESA & NASA)

Click here to watch short videos of computer simulations created by the Center for Integrated Space Weather Modeling.

On October 18, 2003, scientists at the Space Environment Center in Boulder, Colo., saw something alarming. The consoles in the center’s forecast room were lighting up with data feeds from satellites and ground-based observatories tracking the sun’s X-ray and radio emissions, as well as the solar wind — high-energy protons and electrons streaming toward Earth at millions of miles an hour. With little warning, a massive and growing cluster of sunspots had appeared on the solar surface. Over the next few days, the scientists noticed two more sunspot groups, one of them 13 times the size of Earth. To the forecasters, that meant one thing: a monster storm was brewing on the sun.

The center, since renamed the Space Weather Prediction Center (SWPC), immediately issued warnings of imminent solar eruptions that could spew high-energy particles into space, irradiating astronauts, knocking out satellites, and overloading electric power grids on Earth. Indeed, before the storms subsided three weeks later, they had destroyed at least one satellite and damaged others, triggered power blackouts, disrupted airlines, and postponed a lot of business dependent on global positioning systems (GPS). The northern lights, colorful evidence of space weather activity, were visible as far south as Florida. In addition, 17 major solar flares, the largest of which could have exposed astronauts to the equivalent of 100 instantaneous chest X-rays, erupted during the storms, leading NASA to repeatedly direct the International Space Station crew to hunker down in shielded areas of the spacecraft.

The damage could have been worse if SWPC and NASA had not sent more than 250 warnings and alerts to astronauts, airlines, electric companies, and the public. Still, experts warn that when the next major space weather event blows in from the sun, we may not be so lucky.

Currently, the solar storm cycle is in a quiet period, but scientists know that things will be revving back up in the next 5 to 10 years, just as NASA prepares to send astronauts on extended missions to the moon and on to Mars and as the world is becoming increasingly reliant on space-based technologies. The looming problem, according to the 2006 federal Report of the Assessment Committee for the National Space Weather Program, is that the nation’s solar storm forecasting capabilities “lack sufficient reliability” and “do not provide useful lead time or information on the magnitude and duration of the event.”

“All this technology, from GPS to wireless communication, is making life better, but then you become more dependent on it and potentially vulnerable to its glitches,” says Jeffrey Hughes, a College of Arts and Sciences professor of astronomy.

Hughes works on the sixth floor of CAS, overlooking the Charles River, in an office decorated with antique maps of his native North Wales and an Inuit bone carving that he acquired while studying the northern lights in the Canadian Arctic. Around the corner from his office, past an Ansel Adams print of the moon rising over Half Dome in Yosemite, sits Jack Quinn, a sharp-featured Colorado native and a research professor of astronomy. Together, Hughes and Quinn head up the multi-institute Center for Integrated Space Weather Modeling (CISM), which works on the front lines of a national effort to increase our preparedness for future solar storms. In addition, some 50 faculty and graduate students from astronomy and the College of Engineering are affiliated with BU’s Center for Space Physics, and many of them also focus on space weather, researching the solar wind, planetary atmospheres, and the movement of high-energy particles in space. They also lead the development of radiation probes and electron imagers that future NASA missions will use to study the Earth’s magnetosphere and the dangers awaiting astronauts who might return to the moon or venture on to Mars.

The National Science Foundation established CISM in 2002 with $40 million spread over 10 years and one goal: to make solar storms as predictable as hurricanes. To do that, scientists must create a model of space weather covering the more than 90 million miles between the sun’s surface and the Earth’s atmosphere. With five years of funding remaining, getting the job done will take the cooperation of astronomers, physicists, and computational scientists from BU and across the country. CISM’s challenge isn’t just to build a model; it’s to create something that both faithfully mimics space weather in the lab and is effective, fast, and reliable when real solar storms threaten.

“Many people have said it wasn’t worth trying to model the whole sun-to-Earth system, that we didn’t understand it well enough,” Hughes says. “Well, this is the experiment. Can we establish that it is worthwhile, or are those people right?”

Threats from above

In September 1859, telegraph service shorted out in the United States and in Europe. NASA researchers have since pinned the blame on a major solar storm, the earliest record of space weather affecting Earth-based communications. Since then, solar storms have caused incidents ranging from radar blackouts in World War II to a 1958 disruption in transatlantic phone service. NASA’s Johnson Space Center began monitoring space weather in 1962 to assist the Apollo missions, which would eventually land men on the moon.

These days, space is no longer the domain of just astronomers and mission control. “All sorts of people on the ground now rely on satellite communications, ranging from farmers using GPS to monitor their crops and position irrigation and fertilizer to people moving big oil platforms around the Gulf of Mexico,” says Quinn.

Consider this: in 2007 alone, 50 years after Sputnik, about 100 satellites were launched, joining nearly 1,000 already orbiting our planet. Many are used for scientific research or by the military, but their commercial uses are multiplying. About 16 million people now subscribe to satellite radio, and between 2000 and 2005, annual sales of GPS more than doubled, to about $20 billion, according to industry research. Wireless communication devices, such as cell phones and the radio-frequency identification tags that track products worldwide, are nearly ubiquitous and are increasingly networked via satellite.

All of these communications and media systems are vulnerable to solar storms, particularly coronal mass ejections (CMEs), the shock waves of solar plasma made up of charged protons and electrons. CMEs can slam into the Earth’s magnetosphere in less than a day and cause huge geomagnetic disturbances that can knock out satellites and overload electric power grids.

In 1989, space weather caused power blackouts for millions in Quebec and the northeastern United States, frying transformers and requiring about $1.2 billion in repairs and upgrades. Less than a decade later, a space weather event disrupted pager service to 45 million Americans, about 80 percent of all subscribers.

Another space storm danger is solar flares, intense bursts of radiation that can reach Earth in minutes, irradiating astronauts and disrupting radio communications, which increasingly concerns commercial airlines. Since the end of the Cold War, airlines have opened new time- and money-saving routes over the North Pole for flights between North America and Asia. In 2005, more than 3,700 commercial flights used this polar route, 10 times the number in 2000. But flying over the pole also renders pilots reliant on high-frequency radio communications, which are vulnerable to solar storms, and every diverted flight costs its airline about $100,000. Likewise, a satellite knocked out by a solar storm can cost hundreds of millions of dollars to replace; the Department of Defense spends $500 million a year mitigating the effects of space weather, according to 2003 congressional testimony by a former SWPC director.

“Satellites now impact everything from when you use your credit card at the gas pump to when you make a call on your cell phone,” says Howard Singer (GRS’72), chief of SWPC’s science and technology infusion branch. But this steady move to satellite-dependent living is on a collision course with an 11-year solar cycle expected to peak in 2011, initiating several years of increased space weather activity. In fact, the 2003 storms occurred more than three years after the last high point in the solar cycle.

“I think we’re coming into an era where the growth of demand for our services is going to be really, really big,” Singer says. If traffic on the SWPC Web site is any indication, that demand is already here. In October 2003, daily hits to the site spiked from an average of half a million to 19 million at the height of the storms.

But when Singer compares SWPC’s forecasting abilities to sister organizations such as the National Hurricane Center and the National Storm Center, he admits that “we’re a little behind.”

For one thing, compared to earthly forecasts, space weather predictions can depend on relatively few observation points for real-time weather data. Two aging satellites, the Solar and Heliospheric Observatory (SOHO) and the Advanced Composition Explorer (ACE), are stationed about a million miles upstream of Earth, monitoring the solar wind as it nears our magnetosphere and providing about an hour’s warning of approaching storms.

“That’s great for determining what space weather conditions are right now,” says Nathan Schwadron, a CAS associate professor of astronomy. “It’s terrible for providing actual warning from those predictions.”

What’s more, SOHO and ACE are vulnerable to the same high-energy particles they’re tasked to observe. Space weather forecasters also use several ground-based solar observatories, magnetometers, cosmic ray observatories, and radars, most of which were not originally designed for solar forecasting.

“We’ve sort of cobbled together a system of space weather observation from the things that we’ve had available,” says Schwadron. “It’s not ideal.”

Check back on Tuesday, February 19, for part two of “BU Profs Brace for Storms from Outer Space.”

Chris Berdik can be reached at cberdik@bu.edu.

1 Comments

One Comment on BU Profs Brace for Storms from Outer Space

  • Kak on 03.10.2012 at 1:41 pm

    I love outer space<3

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