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Mysterious X-ray signal from space

A mysterious X-ray signal has been found in a detailed study of galaxy clusters using NASA’s Chandra X-ray Observatory and ESA’s XMM-Newton. One intriguing possibility is that the X-rays are produced by the decay of sterile neutrinos, a type of particle that has been proposed as a candidate for dark matter.

While holding exciting potential, these results must be confirmed with additional data to rule out other explanations and determine whether it is plausible that dark matter has been observed.

Astronomers think dark matter constitutes 85% of the matter in the universe, but does not emit or absorb light like “normal” matter such as the protons, neutrons, and electrons that make up the familiar elements observed in planets, stars, and galaxies. Because of this, scientists must use indirect methods to search for clues about dark matter.

A giant collection of galaxies immersed in hot gas about 250 million light years from Earth. This image shows a new view of the Perseus cluster, one of the galaxy clusters included in the new study. (Image  NASA/CXC/SAO)

A giant collection of galaxies immersed in hot gas about 250 million light years from Earth. This image shows a new view of the Perseus cluster, one of the galaxy clusters included in the new study. (Image

The latest results from Chandra and XMM-Newton consist of an unidentified X-ray emission line, that is, a spike of intensity at a very specific wavelength of X-ray light. Astronomers detected this emission line in the Perseus galaxy cluster using both Chandra and XMM-Newton. They also found the line in a combined study of 73 other galaxy clusters with XMM-Newton.

“We know that the dark matter explanation is a long shot, but the pay-off would be huge if we’re right,” said Esra Bulbul of the Harvard-Smithsonian Center for Astrophysics (CfA) in Cambridge, Mass., who led the study. “So we’re going to keep testing this interpretation and see where it takes us.”

The authors suggest this emission line could be a signature from the decay of a “sterile neutrino.” Sterile neutrinos are a hypothetical type of neutrino that is predicted to interact with normal matter only via gravity. Some scientists have proposed that sterile neutrinos may at least partially explain dark matter.

“We have a lot of work to do before we can claim, with any confidence, that we’ve found sterile neutrinos,” said Maxim Markevitch, a co-author from NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “But just the possibility of finding them has us very excited.”

One source of uncertainty is that the detection of this emission line is pushing the capabilities of the two observatories in terms of sensitivity. Also, there may be explanations other than sterile neutrinos if this X-ray emission line is deemed to be real. There are ways that normal matter in the cluster could have produced the line, although the team’s analysis suggested that all of these would involve unlikely changes to our understanding of physical conditions in the galaxy cluster or the details of the atomic physics of extremely hot gases.

The authors note that even if the sterile neutrino interpretation is correct, their detection does not necessarily imply that all of dark matter is composed of these particles.

“Our next step is to combine data from Chandra and JAXA’s Suzaku mission for a large number of galaxy clusters to see if we find the same X-ray signal,” said co-author Adam Foster, also of CfA. “There are lots of ideas out there about what these data could represent. We may not know for certain until Astro-H launches, with a new type of X-ray detector that will be able to measure the line with more precision than currently possible.”

Because of the tantalizing potential of these results, after submitting to The Astrophysical Journal the authors posted a copy of the paper to a publicly accessible database, arXiv. This forum allows scientists to examine a paper prior to its acceptance into a peer-reviewed journal. The paper ignited a flurry of activity, with 55 new papers having already cited this work, mostly involving theories discussing the emission line as possible evidence for dark matter. Some of the papers explore the sterile neutrino interpretation, but others suggest different types of candidate dark matter particles, such as the axion, may have been detected.

Only a week after Bulbul et al. placed their paper on the arXiv, a different group, led by Alexey Boyarsky of Leiden University in the Netherlands, placed a paper on the arXiv reporting evidence for an emission line at the same energy in XMM-Newton observations of the galaxy M31 and the outskirts of the Perseus cluster. This strengthens the evidence that the emission line is real and not an instrumental artifact.


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  • Once again, I would enjoy refuting your so called forensic evidence of creationism, but I can see that you fear TRUTH, since you will not even post one single piece of this so called evidence.
    Here, I will offer you a scientific proof and question and see if you can dispute it. If TIME (Transitional Information, Matter, and Energy) occupies all of existence, how can entropy affect it? Since as it occupies all of space there is nothing outside of its body or its elemental structure, what then can apply the force of entropy to its external self?

  • I would prefer all of these scientists to determine how a galaxy is formed prior to all of this extremely technical science that relatively few people will ever understand because so few people deal with neutrino’s, atoms, quarks, etc. But since this has already been fully described in the book “TIME IS EXISTENCE”, I suppose it will be sufficient to await its complete validity before any of these other scientists even come close to this most important discovery.

    Can you imagine that science is still trying to determine what time is? How is it that they cannot make the connection between the word time and Transitional Information, Matter, and Energy (TIME) since our entire universe and existence is composed only of these elements. TIME is a complete phenomenon, it is not just the ticking of a clock, or some philosophical idea, but a real agent,

    Perhaps, this is why so many other theories like creationism, evolution, and others cannot stand up to the test of TIME, because they completely ignore the elements of transitional information, matter, and energy. These are the only real elements of our existence, and yet, science and religious believers continue to ignore them, one can only wonder why? Well, there is a reason, but you have to read the book to get it.

    Want to know why gravity doesn’t really exist, why dark matter and dark energy approaches are doomed to fail, what time is in its full splendor, take a bit of time and examine this new and complete theory of time and existence, all you have to lose is the old ideas that will never answer the most important questions you will ever need to know.

    • darketernal

      You have to understand that time is a man made concept, it was first thought to be a constant, but now it is understood to be relative constant. So how is this possible? What we refer to as a time, is actually a reference to a pattern. The speed of this pattern is determined by how fast quarks are able to move around inside of a atom. Under the forces of gravity, the movements inside of a atom slow down. For this reason a clock would tick much slower in a high gravity area , like nearby a black hole. Experiments even proved that a clock put on the ground ticks slower then a clock 5 meters up in the air.

      So in other words time equals atomic movement. Gravity acts like a type of friction on atomic movement, thus slowing it down.

      I don’t think you should have any preference for scientists to explain how galaxies are formed, it is explained in some youtube video’s. And i don’t mind scientists saying complicated stuff, it keeps the regular audiences who are willing to peek into this fascinated. Its up to regular people to decide how deep they want to dive into this subject. As for galaxies, we know that after the big bang, there were gigantic stars which lived only for a couple of million of years, the explosions in these stars created gigantic black holes, around these black holes gas collected , which due to gravitational forces created gigantic pressures which exceeded 1 million degrees celcius, thus igniting a hydrogen fusion reaction, and thus creating the stars that we see around black holes, which created the galaxies we can now see in space.

      However this was off-topic because this article was about receiving a signal from a cluster of galaxies.

      • I think you should re-examine your theoretical approach to TIME. For instance, Your application of gravity in your example has nothing to do with the non-existent force of gravity. The reason why a clock moves slower from one point to another is not related to gravity, but rather is a direct result of pressure and force within the atmosphere of Earth.
        The greatest amount of pressure/force on our planet is located near the surface of the planet. This is the result of the equal and opposite force reaction that is absolute, meaning the amount of force applied to the surface is derived from the interaction of solids vs gases or the body of our planet vs the pressure of its atmosphere.
        The reason a clock would move slower is because as it is moved upward toward the atmosphere of earth it will move slower because their is less force being applied to its mechanical parts. Less force equals slower movement. It has nothing to do with light or gravity, only simple force interaction. This is the same type of action that occurs as you move deeper and deeper into water. The pressure affects your cells and will result in the bends if you come back to the surface to quickly.
        I understand that Einstein undermined the laws of Sir Isacc Newton’s motion and force by relating them through light and the illogical and scientifically invalid concepts of General Relativity, but the laws of motion and force are the only logical and scientifically valid way to help explain the activities within our universe and the realm of TIME.
        One other thing, this so-called fascination for regular people has led to the creation of all kinds of ridiculous ideas and conflict. The purpose of science is to relate and describe existence and the activities within it, not to fascinate people.
        All comments within this post are the sole property of the copyrighted book, TIME IS EXISTENCE, and cannot be republished or reprinted without the express permission of the author.

  • Name This

    I don’t know if I would characterize that as a ‘spike’.

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