The Most Energetic Flashes of Light in the Universe Produce Deadly Nuclear Reactions

[Judi Lynn]

By Paul Sutter 15 hours ago

Don't get anywhere near these gamma-ray bursts.



A NASA illustration shows a neutron star surrounded by a disk of matter.
A NASA illustration of a neutron star surrounded by its accretion disk. A new study suggests that gamma-ray bursts from colliding neutron stars could release deadly radiation at a far wider angle than previously thought.
(Image: © NASA)

Gamma-ray bursts are among the most powerful events in the universe, ignited when stars die in massive explosions or when they merge in … massive explosions.

As these violent cosmic explosions occur, they act like cosmic lighthouses, releasing beams of some of the brightest light in the universe, along with a flood of neutrinos, those wispy, ghost-like particles that slip through the universe almost entirely undetected.

Clearly, you would not want to be exposed to one of these deadly, DNA-frying energy bursts. But physicists used to think gamma-ray bursts were dangerous only if you were in the narrow path of one of the jets coming from the explosion. Unfortunately, a new study updated on the arXiv database Nov. 29 (but not yet peer-reviewed) suggests that these eruptions are bad news all around and may send deadly rays at a far wider angle than previously thought.

Cosmic gamma-ray factories
Over the decades, astronomers have identified two kinds of celestial gamma-ray bursts (called GRBs for short): long ones lasting more than 2 seconds (up to several minutes) and short ones lasting less than 2 seconds. We're not exactly sure what causes GRBs out in space, but it's thought that the long ones are produced when the largest stars in our universe die off in supernova explosions, leaving behind neutron stars or black holes. A cataclysmic death like that releases blindingly huge amounts of energy in a relative flash, and voila! Gamma-ray bursts.

More:
https://www.space.com/gamma-ray-bursts-are-deadlier-than-thought.html

[NNadir]

1. Deadly to whom?

It is, I think, an abuse of language to say that gamma rays are "deadly" when there is no one who has been killed by them.

I understand the idea of a thought experiment, but gamma rays are fairly common in space, where very few people live, and, for that matter, very common on Earth, where they also have a fairly good record of killing very few people.

[mbusby]

2. Gamma rays...

...can both cause cancer and kill cancer.

[NNadir]

3. In deep space?

I don't think so.

[localroger]

4. Intensity matters

It's not theoretical to work out how intense the radiation from a GRB is at various distances and compare that to the effects of radiological sources that do exist on Earth. GRB's are considered "deadly" because they would be deadly to all life even at interstellar distances -- in some cases thousands of light-years from the source. Just one of these objects can make a significant volume of the galaxy unsuitable for living things in the long haul.

[NNadir]

5. I think I understand the physics and biophysics of gamma rays. That's not the point.

It's about language, or rather the abuse of language.

The fact is that gamma rays are not deadly in this case because it is very unlikely that in this particular situation there is anything to kill.

It would be fine to say "deadly air pollution" because on this planet, air pollution actually kills people, about 7 million per year.

It would be fine to say "deadly automobiles," because automobiles kill hundreds of thousands people per year.

It would be fine to say "deadly seawater" because early in this century, seawater from two tsunamis killed hundreds of thousands of people.

We do generate intense gamma radiation here on this planet, rather routinely. It has not generally been "deadly" or at least not as deadly as air pollution, automobiles or seawater.

It wouldn't matter except for this; the psychological association of "deadly" and "gamma rays" leads to ignorance that is, in fact, killing the planet. It's called climate change. A particular form of air pollution, specifically carbon dioxide, dangerous fossil fuel waste, is killing the entire planet at an increasing rate. As I often point out, the generation of gamma rays is the only conceivable solution to this problem.

Saying that gamma rays wherever they exist, are "deadly" is just pure nonsense, particularly in a huge astronomical object that obviously cannot support life. It is this awful abuse of language by journalists, among whom clearly there is a dearth of scientific educations, that contributes to common and massive ignorance.

[localroger]

6. That's splitting an odd hair

Polonium is deadly even if you don't put it in anybody's coffee. Gunfire is deadly even if every bullet doesn't hit a person. GRB's are deadly because, if one were to hit an inhabited world, then lots of living things would die. And this isn't theoretical even in the Earth's case; it's thought that a GRB was responsible for at least one of the Earth's mass extinction events. Because they are deadly over such a large area, the chance that Earth will be in the deadly zone for one of them becomes nontrivial over geological time.

[NNadir]

7. You're entitled to your opinion.

Except, of course, the case of Alexander Litvinenko, and as a decay product of radon gas from uranium ores, polonium is not especially "deadly" on scale. The case of the decay of uranium ores has persisted since the formation of the Earth, but has unlikely to have been as "deadly" as seawater has been to human beings, at least.

Since evolution is driven by mutation, and mutations may be generated via irradiation, both industrially, and throughout the history of life, I could argue that there would be no human life without radiation, in the same specious way you cite a putative historical gamma ray burst.

However, in a rational context, in fact, gasoline has killed far more people than polonium ever will, since it is expensive to isolate from lead.

You think it's "hair splitting" to consider the case of my argument, and then go on to make a specious claim about an astronomical event that took place in a time that there was no human life. One wonders however, if human life would have evolved at all without that obviously incomplete sterilization event.

I think you are abusing of language in this case.

The industrial production of gamma rays has saved nearly two million lives, according to a scientific paper I routinely link in this space:

Prevented Mortality and Greenhouse Gas Emissions from Historical and Projected Nuclear Power (Pushker A. Kharecha* and James E. Hansen Environ. Sci. Technol., 2013, 47 (9), pp 4889–4895)

It is also the case that gamma radiation has been used in cancer therapy.

It would be less of an abuse of language, therefore, if we said "life saving" gamma rays than to say "deadly" gamma rays, even though gamma rays are in fact, used to kill potentially pathogenic organisms.

If I note that antibiotics are also used to kill pathogenic organisms, should I then announce the existence of antibiotics as "deadly antibotics?"

The problem with the abuse of language is to act as if conditional statements, those beginning with "if" and "could" and "might" are treated as if they were the same as existence statements.

On this planet, over the last century, gamma radiation has clearly saved more lives that it has killed. This is an experimental fact. Therefore, whether or not you are comfortable with abusing language by making associations that are based on conditional statements, I am not, and I completely disagree with the statement that I am "splitting hairs."

Ignorance thrives on subtle associations that are not justifiable. I consider such abuse of language to be a critical issue not just in science, but in politics, in justice, and in producing a survivable future. To me, it is an important point and I do not apologize for objecting to such abuse of language.

[localroger]

8. This is a strangely intense reaction to a rather bland statement

Nobody has said that radiation in a generic sense is dangerous. What was said is that the amount of radiation generated by a GRB is of deadly intensity over a very large volume of space, extending thousands of light-years from the source. That is a factually verifiable statement. The fact that a deadly thing doesn't kill anyone at a particular time doesn't make it not-deadly; for example, to take one of your examples, gasoline is deadly. That is an actual fact. This is why there are all those safety signs at the petrol station. People have died because they got covered in the stuff and launched a spark. Gasoline is also very useful and necessary to our civilization; the two things are not mutually exclusive.

The probability that the Earth has been in the deadly zone of a GRB within the Milky Way in the roughly 3.5 billion years we are certain it has had living things on its surface is about 50 percent. That is a very high percentage for an event that is likely to sterilize half the planet. At the moment we are not aware of any magnetars close enough to Earth to be deadly to human life, and that isn't likely to change in human timescales, but it is likely to change over geological timescales and it may have had a discernible effect on the history of life.

The main point of the OP is that we have traditionally thought that GRB's are highly directional, and so the deadly zone is relatively focused and narrow. But this new type of GRB event may not be so tightly focused, and might represent a deadly threat to a much larger volume of space. That isn't likely to increase the immediate threat, as we have a pretty good handle on how many neutron stars close enough to put us in the danger zone. But it might increase the historical probability which could affect our view of mass extinctions, among other things.

[Silent3]

9. I agree. That's some weird hair-splitting you're doing, at odds with common (and sensible)...

...use of language. "Deadly" is used all of the time to describe things that merely have the potential to be deadly under both realistic and hypothetical circumstances, and without any need to avoid the term "deadly" for things that can also, in different circumstances, be helpful.