February 2016 Space Security

Defending Earth against cosmic hazards

The devastating impact of an asteroid striking Earth near a centre of population
The devastating impact of an asteroid striking Earth near a centre of population
Scott Madry Executive Director, the Global Space Institute, North Carolina, USA
Ram Jakhu Institute of Air & Space Law, McGill University, Canada
Joseph N. Pelton International Association for the Advancement of Space Safety (IAASS)

Sir Arthur Clarke was fond of quoting his fellow science fiction writer Larry Niven and he often cited Niven’s famous lines, ‘The dinosaurs became extinct because they didn’t have a space programme. And if we become extinct because we don’t have a space programme, it’ll serve us right!’ This seemingly whimsical observation about the end of the dinosaurs and the rise of mammals is actually a rather profound statement on the human condition. Niven’s sardonic quote goes right to the heart of the issue. Do we have the will and the ‘smarts’ to survive and has human space science risen to a level sufficient for us to identify significant cosmic hazards that could threaten the survival of the human race and then respond proactively?

This is one of the key issues addressed by the McGill University Institute of Air and Space Law project - the Global Space Governance Study, an interdisciplinary study guided by the Montreal Resolution of May 2013 and unanimously adopted by over 100 space scientists and space lawyers, involves not only the technological capabilities but also institutional and regulatory actions that might be needed to pursue a viable planetary defence strategy.

We remained largely ignorant of such cosmic dangers until the Space Age began in the 1950s. For the first time we were able to design space probes with sensors that allowed us to look at the characteristics of the geomagnetosphere, discover the Van Allen belts and determine the composition of our upper atmosphere, each of which helps protect life on Earth.

Recent experience and scientific studies suggest there are dangers from cosmic radiation that truly need to be taken seriously

In some ways it is like playing Russian roulette with a random set of rocks, metallic bullets and solar storms that are frequently putting humanity at some degree of risk. The kind of danger ranges from a major urban catastrophe in the form of a ‘city-killer’ asteroid, to loss of modern infrastructure around the world from a massive coronal mass ejection, to total destruction of a species by a gigantic comet or asteroid that could wipe out life as we know it.

McGill University’s Global Space Governance Study lists the top three cosmic hazards that threaten Earth today as:

  • Solar flares and solar storms known as coronal mass ejections (CMEs)
  • Changes to Earth’s magnetosphere that eradicate effective shields to ward off solar coronal mass ejections
  • Potentially hazardous asteroids and comets that can rain down mass destruction.

There are other hazards from space, including the human-generated problem of orbital debris. Even climate change - a complex issue that involves the interaction of human industry and solar radiation on Earth’s atmosphere - is a form of solar threat, though this is not addressed here.

A long filament erupted on the Sun on 31 August 2012 and was imaged by NASA’s Solar Dynamics Observatory (SDO) A long filament erupted on the Sun on 31 August 2012 and was imaged by NASA’s Solar Dynamics Observatory (SDO)

Earth is a constantly bombarded not just by solar radiation but by cosmic radiation originating from the nuclear reactions in stars, from novae and supernovae and even pulsars. Recent experience and scientific studies suggest there are dangers from cosmic radiation that truly need to be taken seriously.

Solar flares and storms

The Sun is our main source of radiation. It showers the Solar System and Earth with energy - particularly in the ultraviolet frequencies and a constant stream of x-rays and gamma rays. Billions of stars are doing the same throughout the universe and current understanding of the Sun, solar flares and coronal mass ejections is derived, in part, by studying other stars in the galaxy and beyond.

Solar activity follows a well-known but not easily understood 11 year cycle that moves from solar minimum to solar maximum. The latest peak in the cycle was reached during the autumn season of 2013. The amount of energy reaching Earth each day, some 93 million miles (149 million km) away from the Sun’s surface, is 10,000 times the total amount that all of humanity actually ‘consumes’.

The 180 km diameter Meteor Crater on the YucatanThe 180 km diameter Meteor Crater on the Yucat

In 1859 a gigantic coronal mass ejection involving billions of tons of ions travelling at millions of kilometres an hour hit Earth in the so-called ‘Carrington event’. Telegraph offices were set on fire and the Northern Lights were seen as far south as Cuba and Hawaii. Had this event occurred today we would have lost electricity power grids around the world, vital telecommunication and space navigation satellites would have been knocked out and oil, gas and water lines would have been impacted. The Montreal ice storm event of 1998 and the Halloween strike in Scandinavia of 2003 are more recent examples of CMEs, both illustrating how coronal mass ejections can knock out power systems and cause problems with vital infrastructures. We don’t know when the next major solar strike will happen, but if a massive stream of ions similar to the Carrington event were to occur the results could be very bad indeed.

An assessment by Lloyd’s of London into the likely impacts of another Carrington-style event estimated the potential adverse economic impacts to be in the trillions of (US) dollars. In the United States the National Intelligence Council has identified such a huge coronal mass ejection as a possible ‘black swan’ event that could do enormous harm to human life and global infrastructure.

It is like playing Russian roulette with a random set of rocks, metallic bullets and solar storms

Solar flares are generated by magnetic reconnections in the Sun that lead to the release of radiation with the power of a thousand atomic bombs, sending high powered x-rays and gamma rays streaming out into space at the speed of light. This ‘radiation explosion’ is different from a CME (which involves a release of mass and ions rather than radiation) but nevertheless constitutes a major concern. Flares have the potential to disable satellites, increase the risk of cancer and result in genetic mutation. In regions of the planet near the ozone hole, skin cancer is 40 per cent higher than the rest of the world. Also, increased genetic mutations in frogs and other life forms have been observed.

As Earth’s population is set to rise from 7.5 billion to between 10 and 12 billion by the end of the century, with corresponding increases in vital infrastructure vulnerable to solar storms and solar flares, the criticality of these solar-based threats will only escalate. The general public has long classified cosmic hazards in the realm of rogue asteroids and comets. Today, solar storms are an ever increasing concern.

Changing geomagnetosphere

Dangers from severe solar storms are a concern not only because there are more people and more electronic infrastructure on the ground and in space but also because the effectiveness of our protective shields - the Van Allen belts and Earth’s magnetosphere and atmosphere - can increase or decrease.

We also know the magnetic North and South poles are shifting. ESA’s Swarm satellites and NASA’s newly launched four-satellite Magnetospheric Multiscale (MMS) mission are providing us more and more information about how Earth’s magnetic field is changing. The geomagnetosphere is about 15 per cent less effective in warding off the supercharged ions in a CME than about 20 years ago.

The B612 Foundation Sentinel infrared telescope that could locate potentially hazardous asteroidsThe B612 Foundation Sentinel infrared telescope that could locate potentially hazardous asteroids

According to Yvon Menard, ESA’s Swarm manager, one likely reason is that Earth’s magnetic poles are getting ready to flip. “Data from our experimental satellites in the skies suggest the magnetic north pole has already moved down to Siberia,” he says.

The assumption is often made that there is no defence against a truly violent storm. But it has been suggested that some sort of cosmic protective engineering might be possible. A deployable magnetic system at the L-1 Lagrangian point coupled with a solar power satellite system might be able to provide a type of shielding that could also transmit solar energy back to Earth 24 hours a day, 365 days a year.

Clearly we need to understand better the physics of solar storms and the nature of changes to the geomagnetosphere. On top of this we might actually begin to consider if we might give new meaning to the term ‘celestial mechanics’ - and begin to consider if we could design a sort of magnetic ‘blinder’ we could apply to the most extreme form of solar storms.

Asteroids and comets

In the last few decades scientists have discovered more and more evidence of the various types of cosmic hazards that lurk in outer space. As recently as 2013, a meteorite crashed over a major Russian town, injured 1100 people and damaged 4000 buildings. In the 1980s a huge circular crater 180 km across and 900 m deep was discovered. The perfectly shaped circular crater ranges along the coast of Mexico’s Yucatan plateau and extends well out into the Gulf.

By the 1990s space imaging was able to confirm that this was indeed the remnant of a giant asteroid that smashed into Earth. This event, which was the equivalent to the explosion of tens of thousands of nuclear bombs and blocked out the Sun with an ensuing cloud of dust, was termed a ‘nuclear winter’. This mass extinction event (known as the K-T) not only killed off the dinosaurs some 66 million years ago but also extinguished over 70 per cent of all plant and animal species that were alive at the time. This was the worst of the Earth’s five mass extinctions and the ultimate verification that it was the result of a huge meteor collision came from space observations.

A more recent wake-up call about space hazards that can crash into planets at supersonic speeds with horrendous destructive force came in 1994 after astronomers witnessed the impact on Jupiter of a multi-part comet as it crashed into the Solar System’s largest planet. This all occurred some 20 years ago when the Comet P/Shoemaker Levy 9 (D/1993 F2) collided with Jupiter.

The comet was first observed on 24 March 1993 by Carolyn and Eugene Shoemaker and David Levy at the Palomar Observatory in California and had, of course, been predicted well before this catastrophic event actually occurred. There were 21 discernible parts to the comet ‘complex’ - with some being as large as 2 km in diameter and during a six day period between 16 and 22 July 1994 pieces of the comet bombarded Jupiter with explosive force that could easily be seen through telescopes. This was the first such collision of two Solar System bodies ever to be observed and recorded - and the impact on Jupiter and its atmosphere were truly frightening.

Each year we learn more about the dangers of asteroid and comet strikes and each year the level of threat increases. Monitoring via GPS satellites have shown that such strikes are four times more common than previously thought. We know that asteroids as small as 30 m (at high enough velocity) are ‘city killers’ and that there are in the order of 500,000 to one million near earth objects (NEOs) of this size and that they are largely uncharted. NASA has in mind to launch a project called NEOCAM and the B612 Foundation (a private non-profit foundation with headquarters in the United States and dedicated to planetary defence against asteroids and other NEOs) is building its Sentinel spacecraft. Both of these infrared telescope satellites could greatly increase our ability to spot the threat of dangerous space rocks that could do potential damage.

The truth is that humans and our modern society are more at risk and the cosmic hazards we face are too dire to ignore or pretend they do not exist. The risks outlined above are not specific to any group of countries but to all nations of the Earth and by necessity attempts to mitigate and manage these perils will be global in nature, scope and participation.

Solar flares lead to the release of radiation with the power of a thousand atomic bombs, sending high powered x-rays and gamma rays streaming into space at the speed of light

United Nations (UN) action to create the International Asteroid Warning Network (IAWN) and the Space Mission Planning Advisory Group (SMPAG) to address potentially hazardous asteroids is one specific step already taken and others will clearly follow.

Close international cooperation, in the form of scientific investigations, exchange of relevant data, development of appropriate technological tools, operational procedures and decision-making, is imperative for effective protection against cosmic risks. We should remain cognizant of the fact that any unilateral action by one state, even by the richest and the most advanced one, might run into numerous legal, regulatory, political, economic and strategic barriers.

The first steps to sort out regulatory processes with regard to asteroids may initially be addressed in terms of national legislation. New legislation in the US - known as the ‘Space Act of 2015’ - is focused on the space mining of asteroids rather than diverting dangerous space rocks from hitting Earth. With the US enacting this type of legislation other national legislation may well follow and this might have the effect of making space activities more competitive rather than cooperative.

The process set up by SMPAG currently gives a lead to countries with the strongest space programmes to propose defensive actions against potentially hazardous asteroids or comets. This, however, might be followed by the United Nations Security Council considering a more specific international treaty (or other form of legal regime) that would be developed by the most interested space-faring states but made open to all. It is important to note that there are other types of cosmic hazards to be considered and the UN COPUOS Working Group on the Long Term Sustainability of Outer Space Activities is an entity that is currently considering issues such as solar flares and CMEs.

In addition, we propose the following seven point actions which are emerging from the McGill Global Space Governance Study. This brief action list is a good indication of what might be done to address cosmic hazards. Clearly more science and investigation is needed - but we are not ostriches that face danger by just opting out and placing our heads in the sand to blot out the impending threat. We are at least hoping that we are smarter than the dinosaurs and more proactive than myopic ostriches.

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