Have Scientists Discovered a Radio ‘Space Shield?’

Have Scientists Discovered a Radio ‘Space Shield?’

Space, it turns out, is not a very safe place for electronic devices.

High-energy space particles can cause serious problems for satellites and electronic equipment, even on the Earth’s surface. These particles usually come from storms on the sun.

But there may be a way to protect against dangerous high-energy particles by using a kind of radio wave.

The magnetic field around the Earth protects it from the effects of many kinds of high-energy particles. This shield is called the Van Allen belt. It was discovered by the first American satellite, Explorer 1, in 1958.

In the years since, scientists have learned the ‘belt’ is really three belts that change in size and shape over time.

One kind of radio wave may be able to provide protection against some high-energy particles. It may even be be able to protect against so-called “killer electrons.”

Scientists call these radio waves Very Low Frequency, of VLF.

Dan Baker¹ is director of the Laboratory of Atmosphere and Space Physics at the University of Colorado, Boulder². His team discovered how these radio waves work.

He said scientists have long been trying to find ways to protect against different kinds of space debris³ and other dangers.

“We’ve been trying to figure out, ‘how can we most effectively eliminate this debris without causing more of a problem?’”

Tiny particles can cause a lot of damage

Space debris can be something as small as a chip of paint or as large as a rocket booster. Even the smallest pieces of debris can be dangerous because they travel at very high speeds as they orbit the Earth.

Baker said high-energy particles that are smaller than an atom, such as the “killer electrons,” also can be a major danger.

“We know, we’ve observed them to cause very significant problems for spacecraft.”

High-energy particles can damage electric circuits in space stations, weather satellites and other machines traveling in space.

“There are over 1,400 satellites operating in space around the Earth and all of those could be subject to very severe consequences,” Baker said.

These kinds of particles can come from human activity; atmospheric⁴ tests of nuclear weapons can send out huge amounts of radiation, including high-energy particles.

“Now what is worrisome to us from a political standpoint today is that there are nations, for example, North Korea and others, that may be thinking once again…that this might be an interesting way to mess with modern technology.”

Even with the protection of the Van Allen belts, radiation from space can cause problems for modern technology.

Satellites built to operate in or above the Van Allen belts must have thicker coverings. That makes them heavier and more costly⁵. But satellites orbiting below the Van Allen belt do not need such heavy shielding.

Scientists have known for years that something from Earth clears away dangerous electrons from lower levels in the Van Allen belts. But what that was remained unclear.

A bubble of protection

Baker’s team found that VLF radio waves improve protection against high-energy particles. He calls the safe area a “bubble.”

VLF waves have unusual properties for radio waves. They are used to communicate with submarines near the surface of the sea. But they also go up into the atmosphere and beyond.

“So the VLF bubble is made up of these intense waves. These waves act to sort of scatter⁶ and scrub the inner part of the Van Allen belt.”

John Bonnell is a researcher with the Space Sciences Laboratory of the University of California, Berkeley. He compared the effect of VLF waves to how lightening clears away electrons from the atmosphere. He said while VLF waves might be considered a form of radio pollution, “the likelihood of there being a bad side effect is pretty minimal⁷.”

Bonnell said the discovery does not necessarily mean that scientists have discovered a way to make a kind of “space shield.” Imagine an energy shield that protects a spaceship from attack in a science fiction movie.

But, Bonnell said, “It’s a fascinating possibility and it’s a fascinating technology that could enable, in the future, us to explore more of the solar system with people, with robots.”

The finding could be an example of how scientists, engineers and astronomers⁸ work together to make a remarkable⁹ discovery. The findings could lead to “shields” that protect costly satellites, spacecraft and even people in the future as they push deeper into outer space.

I’m Mario Ritter.

Words in This Story

particles –n. part of something, such as an atom, not a whole

debris –n. pieces left after something has been broken up

circuitry –n. the workings of an electronic device that govern electrical flow

consequences –n. results

adherent¹⁰ –n. the state of following a system of beliefs or rules

mess –n. a group of disorganized things

scatter –v. to force apart and send to different areas

scrub –v. to clear using forceful action

minimal –adj. the least amount

fascinating –adj. very interesting

1 baker   

n.面包师

参考例句：

• The baker bakes his bread in the bakery.面包师在面包房内烤面包。
• The baker frosted the cake with a mixture of sugar and whites of eggs.面包师在蛋糕上撒了一层白糖和蛋清的混合料。

2 boulder   

n.巨砾；卵石，圆石

参考例句：

• We all heaved together and removed the boulder.大家一齐用劲，把大石头搬开了。
• He stepped clear of the boulder.他从大石头后面走了出来。

3 debris   

n.瓦砾堆，废墟，碎片

参考例句：

• After the bombing there was a lot of debris everywhere.轰炸之后到处瓦砾成堆。
• Bacteria sticks to food debris in the teeth,causing decay.细菌附着在牙缝中的食物残渣上，导致蛀牙。

4 atmospheric   

adj.大气的，空气的；大气层的；大气所引起的

参考例句：

• Sea surface temperatures and atmospheric circulation are strongly coupled.海洋表面温度与大气环流是密切相关的。
• Clouds return radiant energy to the surface primarily via the atmospheric window.云主要通过大气窗区向地表辐射能量。

5 costly   

adj.昂贵的，价值高的，豪华的

参考例句：

• It must be very costly to keep up a house like this.维修这么一幢房子一定很昂贵。
• This dictionary is very useful,only it is a bit costly.这本词典很有用，左不过贵了些。

6 scatter   

vt.撒，驱散，散开；散布/播；vi.分散，消散

参考例句：

• You pile everything up and scatter things around.你把东西乱堆乱放。
• Small villages scatter at the foot of the mountain.村庄零零落落地散布在山脚下。

7 minimal   

adj.尽可能少的，最小的

参考例句：

• They referred to this kind of art as minimal art.他们把这种艺术叫微型艺术。
• I stayed with friends, so my expenses were minimal.我住在朋友家，所以我的花费很小。

8 astronomers   

n.天文学者，天文学家( astronomer的名词复数 )

参考例句：

• Astronomers can accurately foretell the date,time,and length of future eclipses. 天文学家能精确地预告未来日食月食的日期、时刻和时长。 来自《简明英汉词典》
• Astronomers used to ask why only Saturn has rings. 天文学家们过去一直感到奇怪，为什么只有土星有光环。 来自《简明英汉词典》

9 remarkable   

adj.显著的，异常的，非凡的，值得注意的

参考例句：

• She has made remarkable headway in her writing skills.她在写作技巧方面有了长足进步。
• These cars are remarkable for the quietness of their engines.这些汽车因发动机没有噪音而不同凡响。

10 adherent   

n.信徒，追随者，拥护者

参考例句：

• He was most liberal where money would bring him a powerful or necessary political adherent.在金钱能够收买一个干练的或者必需的政治拥护者的地方，他是最不惜花钱的。
• He's a pious adherent of Buddhism.他是一位虔诚的佛教徒。