Space Debris and Other Threats From Outer Space (7 page)

Of greatest concern of all is to understand the threat that coronal mass ejections pose to the safety of people within Earth’s atmosphere. Today, airlines that fly polar routes to reach destinations faster and to save fuel, have learned to alter these polar routes when there is a major coronal mass ejection event or gamma ray and solar radiation are at elevated levels.

The issue of elevated radiation and implications of the variation in the ozone layers and the varying sizes of the so-called polar ozone holes are addressed in the following chapter.

 

This chapter continues the discussion that was started in the previous chapter with regard to solar events and activities that provide hazards to people here on Earth. What is clear is that solar and cosmic radiation from other sources beyond actually poses a hazard to flora and fauna on Earth. Most certainly this high-powered radiation provides a particular danger to astronauts. There is continuous radiation reaching Earth from the Sun and cosmic sources throughout the universe. These rays are distorted from a direct hit on Earth by Earth’s geomagnetic field.

Powerful and intense ultraviolet and cosmic radiation, particularly high energy gamma rays if not bent away by Earth’s geomagnetic, would create a deadly environment on Earth. In addition there are clouds of poison gas in the upper atmosphere such as hydrogen cyanide that are warded off by the geo-magnetosphere as well.

Super energetic X-rays travel from the Sun and across interstellar space. This radiation is continuously raining down from the cosmos and may be elevated during solar max and during CME events, but this is a natural phenomena that is always present. Without the Van Allen belts, Earth’s atmosphere, stratosphere and ionosphere, radiation would be a true killer for virtually all life on Earth. When we search for life in outer space we must not only look for Earth-like planets in terms of size, water, and warmth, but planets with a protective atmosphere as well.

The ultraviolet and X-ray radiation from the Sun are a particular hazard to astronauts who are exposed to high levels of damaging rays that those of us who live within Earth’s protected atmosphere are not. An astronaut on-board the International Space Station may receive an exposure to radiation that is much higher to someone on Earth and thus radiation levels have to be carefully monitored. In the case of surges in radiation levels there is a protective compartment on-board the ISS where astronauts and cosmonauts can seek shelter. If at a future date there were to be a permanent lunar colony, it would likely need to be built below the surface to protect the astronauts and cosmonauts from the harmful radiation and high energy mass ejaculates from the Sun characterized as “space weather”.

This high energy radiation can also be quite harmful to humans here on Earth. The ozone layer helps protects all flora and fauna against genetic mutations triggered by cosmic radiation in addition to the vital protection provided by the inner and outer Van Allen belts. The screening out of ultraviolet rays by solar backscatter from the naturally occurring ozone layer helps to reduce the ultraviolet radiation threat to humans and other animals in terms of both skin cancer and genetic mutation. If “ozone holes” now significantly detected in the polar regions should extend their diameter to a greater size then humans and indeed most animals would most certainly be at increased risk of both genetic mutation and cancer.

It is through space research that the holes in the protective ozone layer were discovered. NOAA has launched nine such sensors on their meteorological satellites. These sensors are geared to detect the level of backscatter of incoming solar ultraviolet radiation in the ionosphere and provide the amount of backscatter that occurs between the altitudes of 6–30 miles (9.6–48 km). These solar radiation sensors called the SBUV/1 and 2 have been flying on the NOAA satellites dating back to the mid 1980s [28]. This monitoring of the “space weather” from the Sun is key in many ways, including the fact that the solar energy released impacts the weather here on Earth. The 11-year cycle as shown here closely mirrors the electro-magnetic flux levels that are released from the Sun as well (Fig. 
7.1
).

These sensing instruments (shown in Fig. 
7.2
) have confirmed the existence of the ozone holes in the polar regions since 1987. These sensors confirm that penetration of the UV radiation at these high latitudes are indeed dangerous.

These are not theoretical observations but confirmed facts that carry with them true health and medical implications. Currently residents in the most extreme southern locations of Australia and New Zealanders, for instance, today report a much higher incidence of skin cancer. In my own travels to Adelaide, Australia, in order to teach for the International Space University, it is difficult to venture out during Aussie summer days without a hat and significant amounts of sunscreen in light of the Sun’s intense radiation effects. Frogs and amphibians in these polar areas have also demonstrated a growing number of genetic mutations.

Earth is protected not only by the ozone layer that resides above the stratosphere but below the ionosphere and the two Van Allen belts as well. Without the protection afforded by these two high energy belts that are shaped by Earth’s magnetosphere and the ozone layer, the plant and animal life of Planet Earth would be subjected to a lethal amount of radiation and plasma that would in a short time likely render our world lifeless. These Van Allen belts are represented in Fig. 
7.3
below.

Although the inner radiation belt was discovered a half century ago by the Geiger counter on board the
Explorer I
spacecraft, and the outer belt was discovered a few years later, there is much we still do not know; the make-up and function of these two belts now named after James Van Allen is still not well understood.

Two identical space probes known as the Radiation Belt Storm Probes were launched in August 2012 to try to understand in much greater depth the way these belts function and why the belts are so different. The two spacecraft, now renamed the Van Allen solar storm probes, have now detected a third belt that "appeared" and then "disappeared" during the early part of 2013. These research probes will fly virtually identical orbits so that the fluctuating conditions within the belts can be monitored. It is hoped that the data collected will indicate how the belts interact with Earth’s magnetic field as well as how they “absorb” solar and cosmic radiation, capture solar ionic materials from coronal mass ejections and space weather and then dissipate it back into outer space.

The Van Allen belts are in a constant state of flux. The inner belts largely consist of protons at high energy levels while the outer belts largely consist of high energy electrons. These belts grow and shrink as they are affected by space weather. In order to make more detailed measurements, the Radiation Belt Storm Probes will use twin satellites following identical paths, sometimes zipping just above Earth’s atmosphere and sometimes many thousands of miles out into space where the outer belt resides. One of these Radiation Belt Storm Probe satellites is seen in the foreground and another one in the far distance is pictured below in Fig. 
7.3
as they would appear as seen from above in orbit.

Traveling through both the inner and outer radiation belts, the crafts will maintain varying distances, sometimes within 100 miles of one another, at other times nearly 25,000 miles apart.

Their separation will allow scientists to get a better feel for changes that occur in the belts. One craft may absorb a spike in radiation levels. What the second craft reads from a different location will reveal a great deal about what is happening in the belts.

In some cases it may read a similar increase. It may only detect the higher levels when it reaches the same region the first craft was traveling through. It may pick up the spike after a slight delay, indicating that the radiation is traveling, wavelike, through the belts. Or it may see nothing at all (Fig. 
7.4
).

There are at times magnetic irregularities and distortions in Earth’s magnetosphere that normally flows upward from Earth’s two magnetic poles that are near the world’s geographic poles as well. At times there are fluctuations in Earth’s magnetic flux system that can serve to bring in deadly cosmic and solar radiation down to the world’s surface.

As early as 1961 James Dungey of the United Kingdom predicted that “cracks” might form in the magnetic shield when the solar wind contained a magnetic field that was oriented in the opposite direction to a portion of Earth’s field. In these regions with the two competing magnetic fields can sometimes interconnect through a process known as “magnetic reconnection”. This process can serve to form a modest crack in Earth’s shield. In this case electrically charged particles of the solar wind as well as ions from the Van Allen belt could flow below the geomagnetic field. This can bring not only deadly radiation but poisonous gases such as hydrogen cyanide.

These small “cracks” were first detected using the International Sun-Earth Explorer (ISEE) satellite as early as 1979. This potentially very serious threat has thus been under study since that time [29].

A joint satellite mission funded by NASA and the European Space Agency, named IMAGE, has been launched to monitor these “cracks” and to determine the degree to which Earth’s geomagnetic field might be weakening and thus increasing these dangerous conditions over time. The IMAGE satellite, as pictured in orbit inside of one of these magnetic gaps, is depicted in Fig. 
7.5
.

If indeed Earth’s geomagnetic field is weakening or if the polarity of the field is switching north to south and vice versa, then it is possible that all of humanity and indeed plant and animal life might be increasingly exposed to energetic electrons, ionic particles as well as deadly gases from the inner Van Allen regions [29].

In the very first days of 2011 there were a number of events around the world—Arkansas and New Orleans in the United States, Italy, New Zealand, Japan, etc., where it seemed that perhaps millions of birds died in a “freak event”. This event is still not fully explained, but one persistent theory developed by Russian scientists is that a deadly cloud of hydrogen cyanide gas was leaked through a crack in Earth’s geo-magnetosphere at an altitude of some 50 miles high. The theory is that enough of this hydrogen cyanide gas leaked through to a lower altitude and this was the cause of the mass death of so many birds all at once. At the same time there were a number of deaths of fish as well. The theory is that the clouds of deadly gas managed to rain down this hydrogen cyanide poison as rainwater and that this mixture was still sufficient to kill freshwater fish as well [30].