Nanodiamonds responsible for mysterious source of microwaves across the Milky Way

June 11, 2018, Green Bank Observatory
Nanodiamonds in the sky. Credit: S. Dagnello, NRAO/AUI/NSF

For decades, astronomers have puzzled over the exact source of a peculiar type of faint microwave light emanating from a number of regions across the Milky Way. Known as anomalous microwave emission (AME), this light comes from energy released by rapidly spinning nanoparticles—bits of matter so small that they defy detection by ordinary microscopes. (The period on an average printed page is approximately 500,000 nanometers across.)

"Though we know that some type of particle is responsible for this microwave light, its precise source has been a puzzle since it was first detected nearly 20 years ago," said Jane Greaves, an astronomer at Cardiff University in Wales and lead author on a paper announcing this result in Nature Astronomy.

Until now, the most likely culprit for this microwave emission was thought to be a class of organic molecules known as polycyclic aromatic hydrocarbons (PAHs) - carbon-based molecules found throughout interstellar space and recognized by the distinct, yet faint infrared (IR) light they emit. Nanodiamonds—particularly hydrogenated nanodiamonds, those bristling with hydrogen-bearing molecules on their surfaces—also naturally emit in the infrared portion of the spectrum, but at a different wavelength.

A series of observations with the National Science Foundation's Green Bank Telescope (GBT) in West Virginia and the Australia Telescope Compact Array (ATCA) has—for the first time—homed in on three clear sources of AME light, the protoplanetary disks surrounding the young stars known as V892 Tau, HD 97048, and MWC 297. The GBT observed V892 Tau and the ATCA observed the other two systems.

"This is the first clear detection of anomalous microwave emission coming from protoplanetary disks," said David Frayer a coauthor on the paper and astronomer with the Green Bank Observatory.

The astronomers also note that the infrared light coming from these systems matches the unique signature of nanodiamonds. Other protoplanetary disks throughout the Milky Way, however, have the clear infrared signature of PAHs yet show no signs of the AME light.

This strongly suggests that PAHs are not the mysterious source of anomalous microwave radiation, as astronomers once thought. Rather, hydrogenated nanodiamonds, which form naturally within protoplanetary disks and are found in meteorites on Earth, are the most likely source of AME light in our galaxy.

"In a Sherlock Holmes-like method of eliminating all other causes, we can confidently say the best candidate capable of producing this microwave glow is the presence of nanodiamonds around these newly formed stars," said Greaves. Based on their observations, the astronomers estimate that up to 1-2 percent of the total carbon in these protoplanetary disks has gone into forming nanodiamonds.

Evidence for nanodiamonds in protoplanetary disks has grown over the past several decades. This is, however, the first clear connection between nanodiamonds and AME in any setting.

Statistical models also strongly support the premise that nanodiamonds are abundant around infant stars and are responsible for the anomalous microwave emission found there. "There is a one in 10,000 chance, or less, that this connection is due to chance," said Frayer.

For their research, the astronomers used the GBT and ATCA to survey 14 young stars across the Milky Way for hints of anomalous microwave emission. AME was clearly seen in 3 of the 14 stars, which are also the only 3 stars of the 14 that show the IR spectral signature of hydrogenated nanodiamonds. "In fact, these are so rare," notes Greaves, "no other young stars have the confirmed infrared imprint."

This detection has interesting implications for the study of cosmology and the search for evidence that our universe began with a period of inflation. If immediately after the Big Bang, our universe grew at a pace that vastly outstripped the speed of light, a trace of that period of inflation should be seen in a peculiar polarization of the cosmic microwave background. Though this signature of polarization has yet to be conclusively detected, the work by Greaves and her colleagues offers some hope that it could be.

"This is good news for those who study polarization of the cosmic microwave background, since the signal from spinning nanodiamonds would be weakly polarized at best," said Brian Mason, an astronomer at the National Radio Astronomy Observatory and coauthor on the paper. "This means that astronomers can now make better models of the foreground microwave light from our galaxy, which must be removed to study the distant afterglow of the Big Bang."

Nanodiamonds likely form out of a superheated vapor of carbon atoms in highly energized star-forming regions. This is not unlike industrial methods of creating nanodiamonds on Earth.

In astronomy, nanodiamonds are special in that their structure produces what is known as a "dipole moment—an arrangement of atoms that allows them to emit electromagnetic radiation when they spin. Because these particles are so small—smaller than normal dust particles in a protoplanetary disk—they are able to spin exceptionally fast, emitting radiation in the microwave range rather than in the meter-wavelength range, where galactic and intergalactic radiation would probably drown it out.

"This is a cool and unexpected resolution to the puzzle of anomalous microwave radiation," concluded Greaves. "It's even more interesting that it was obtained by looking at protoplanetary disks, shedding light on the chemical features of early solar systems, including our own."

"It is an exciting result," concluded co-author Anna Scaife from Manchester University. "It's not often you find yourself putting new words to famous tunes, but 'AME in the Sky with Diamonds' seems a thoughtful way of summarizing our research."

Future centimeter-wave instruments, like the planned Band 1 receivers on ALMA and the Next Generation Very Large Array, will be able to study this phenomenon in much greater detail. Now that there is a physical model and, for the first time, a clear spectral signature, astronomers expect our understanding will improve quickly.

Explore further: Dusty protoplanetary disks

More information: Anomalous microwave emission from spinning nanodiamonds around stars, Nature Astronomy (2018). DOI: 10.1038/s41550-018-0495-z ,
https://www.nature.com/articles/s41550-018-0495-z

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RealityCheck
1.4 / 5 (11) Jun 12, 2018
@RNP et al.

Yet another of the myriad ways/processes I have been pointing out for so long now; ie, that CMB is being created 'now' and 'everywhere' we look across the cosmos. No Big Bang, Inflation, Dark Energy etc 'source' or 'interpretations/explanations' needed. How many times do I have to point it all out before you, RNP et al, finally stop ignoring/denying, and finally catch up with mainstream which is itself finally (even over the last few days/weeks in relevant PO articles) discovering/acknowledging ever more of those things that I have been ahead of the curve on for decades now? Time to listen and stop your unheeding 'crusade' against someone who has been trying to help you all become more objectively/correctly informed re the actual Universal physical reality phenomena around you. Try. :)
jonesdave
5 / 5 (11) Jun 12, 2018
^^^^Nope, this is foreground emission, from very small areas in the milky way. As such it would have been removed from the CMB maps. I would suggest emailing somebody from the WMAP, Planck or COBE teams who will no doubt tell you the same.
RealityCheck
1 / 5 (7) Jun 12, 2018
@jonesdave.
Nope, this is foreground emission, from very small areas in the milky way. As such it would have been removed from the CMB maps. I would suggest emailing somebody from the WMAP, Planck or COBE teams who will no doubt tell you the same.
I have long been trying to get you, RNP et al to 'connect the dots' further afield than just the particular instance/context being reported on in any one study.

Try to push through the one local context 'here', and consider the implications for CMB observed of ALL those 'local' contexts 'there', in all radial directions extending to the furthest observational horizon distance.

Can you not see that when added up it effectively adds to the background totality of CMB we see from 'here'?

Add these 'ordinary' (ie, non-BB etc) sources throughout the universe, then add further all the other ordinary ways/processes for CMB production I have long listed for your consideration...and 'connect all the dots' for yourself. Go on. :)
jonesdave
5 / 5 (11) Jun 12, 2018
Can you not see that when added up it effectively adds to the background totality of CMB we see from 'here'?


Nope. And neither can anyone else by the looks of it. Doesn't even appear to be at the same frequencies, from what I can see. However, like I said, a quick email to an expert on these surveys would likely soon disabuse you of this rather naive conclusion.

RealityCheck
1 / 5 (9) Jun 12, 2018
@jonesdave.
Doesn't even appear to be at the same frequencies, from what I can see. However, like I said, a quick email to an expert on these surveys would likely soon disabuse you of this rather naive conclusion.
Hehe. Considering how long I have been pointing out the naivete' of BB etc assumptions and interpretations of the observed CMB, it is somewhat ironic (not to say amusing) to hear myself being accused of naivete' by one who has subscribed to and been affected by all the decades of naive BB assumptions/interpretations.

Just goes to show how deeply 'inculcated' BB naivete is. :)

Consider all the uncountable repeated interactions, not just 'one offs', and you'll understand how 'serial attenuation' can produce a range of frequencies, including CMB ones. That goes for all the other CMB producing processes/frequencies that I have long alluded to. Its more complex/expansive than naive BB 'view' of things. It requires much cross-discipline, wide ranging view. :)
jonesdave
5 / 5 (9) Jun 12, 2018
^^^^^Just write it up, eh? Or link us to somebody actually qualified who agrees with you. Otherwise it is just more crankery in a sea of crankery.
RealityCheck
1 / 5 (5) Jun 12, 2018
By the way mate, before I log out for the day, I'd like to ask you to peruse, and sleep on it overnight, my post re Neutrino 'oscillation' over at thread:

https://phys.org/...ion.html

When next we 'speak' (hopefully tomorrow), I'd like your scientific opinion on my perspective on that subject therein; but only if you are interested and have the time, of course. Thanks and g'night, mate. :)
RNP
5 / 5 (10) Jun 12, 2018
@Realitycheck
I have been pointing out for so long now; ie, that CMB is being created 'now' and 'everywhere' we look across the cosmos.

This clearly shows that you do not even know what the CMB is.

Of course the are sources of microwave radiation, but they do NOT produce the almost PERFECT black body spectrum observed in the CMB, nor are they as incredibly evenly spread acrosss the whole sky (1 part in 100,000) as the observed CMB. In fact, these sources are subtracted from the observed microwave observations to leave the CMB as the residual.

I have long been trying to get you, RNP et al to 'connect the dots'

Your problem is that I and the others are not willing to waste our time trying to connect your randomly generated "dots".

Go back to school and learn the actual physics, then come back and try talking to the grown-ups about this (or any other) subject.
RealityCheck
1 / 5 (9) Jun 12, 2018
@jonesdave.
Or link us to somebody actually qualified who agrees with you. Otherwise it is just more crankery in a sea of crankery.
Try to do some original research/thinking for yourself given the presented facts/science involved. Don't just abdicate the duty you have to The Scientific Method. It's all there in the mliterature; it only needs those who can 'connect the dots' for themselves to get up the courage and investigate properly and objectively.

Anyhow, in case you are daunted/unfamiliar with some relevant aspects not immediately apparent at naive first glance, may I suggest you learn what happens in other 'serial interaction' contexts? For example, in META-MATERIALS and other 'waveguide' structures affecting light 'direction' and/or 'frequency' and or other property changes of photons. Also read up on what happens to light going through bose-einstein condensates (especially relevant in cryogenically cold 'clouds' in deep space).

G'night again, jd. :)
RealityCheck
1 / 5 (9) Jun 12, 2018
@RNP.
Of course the are sources of microwave radiation, but they do NOT produce the almost PERFECT black body spectrum observed in the CMB, nor are they as incredibly evenly spread acrosss the whole sky (1 part in 100,000) as the observed CMB. In fact, these sources are subtracted from the observed microwave observations to leave the CMB as the residual.
It's the naive BB biased interpretation again, mate. Stop to consider all the aspects I have been pointing out that produce exactly that given the time and distance travelled from all the myriad sources/processes in/from all directions.
Your problem is that I and the others are not willing to waste our time trying to connect your randomly generated "dots".
Mainstream increasingly coming round to my longstanding points; but you and "others" haven't time to 'waste' updating yourselves beyond deeply-inculcated BB-naive 'understanding' of CMB? Not my problem, mate. :)

Have to go. G'night, RNP, all.
RNP
5 / 5 (9) Jun 12, 2018
@Realitycheck
Yet again you are talking complete balderdash. The mainstream clearly identifies you claims as completely false, as evidenced by the fact that you can not give even a single reference that supports your silly claims. I will waste no more time on you.
granville583762
3 / 5 (4) Jun 12, 2018
The correlation between the cosmic background radiation and anomalous microwave emission
The cosmic background radiation where the temperature dropped allowing electrons and protons to form hydrogen atoms
Microwave light emanating from proto planetary disks across the Milky Way, anomalous microwave radiation comes from energy released by rapidly spinning nano particles, hydrogen atoms 500,000 nanometres
The connection appears to involve the base ingredients of the vacuum of space protons and electrons or more precisely quarks, electrons and neutrino's
As anomalous microwave radiation and background radiation are emanating from hydrogen nuclei and both are emanating from proto planetary disks because in the dust is where the original hydrogen atoms were formed in the original primordial soup
Nothing has changed in 15billion years we are still dealing with hydrogen atoms radiating electromagnetic radiation from the primordial dust which is what proto planetary disks consists of.
thingumbobesquire
not rated yet Jun 12, 2018
Lucy in the sky with nano-diamonds?
antialias_physorg
5 / 5 (2) Jun 12, 2018
Lucy in the sky with nano-diamonds?

That would have been more healthy than the 'diamonds' the Beatles were referring to.
granville583762
2.6 / 5 (5) Jun 12, 2018
Where is the Nobel Prize in all this?

I like this article; not a dark molecule in sight, no MOND, no Aether, no Higgs field - just quarks, electrons and neutrinos going through their natural daily life unmodified by human kinds over imaginative imagination to the point we appear to have found a present day source of background radiation that has been carried out in the vacuum of space for 15billion years, that's almost identical to the length of time before human kind poked his intellectual oar in relatively speaking a few 100years ago.

What is intriguing in this discovery which on galactic scales has enormous consequences and possibilities, no one has submitted this for recommendation for a Nobel Prize.
antialias_physorg
5 / 5 (4) Jun 12, 2018
What is intriguing in this discovery which on galactic scales has enormous consequences and possibilities

And I'm sure you can list those enormous consequences and possibilities for the rest of us? Or did you just make that up to try and sound smart?
granville583762
2.6 / 5 (5) Jun 12, 2018
For want of the many possibilities for your Nobel Prize applications!
granville583762> What is intriguing in this discovery which on galactic scales has enormous consequences and possibilities

antialias_physorg> And I'm sure you can list those enormous consequences and possibilities for the rest of us? Or did you just make that up to try and sound smart?

One possibility is in matter expelled out of our light radius stars spin axis into their star forming Fermi bubbles, the material ejected is in the same form as the original 15billion year old primordial soup emitting the same background radiation to this present day in our galaxies.

One of the very deserving reasons for application and as one Nobel leads to another Nobel there's limitless room in the vacuum of space if more are required!
granville583762
2.6 / 5 (5) Jun 12, 2018
This present article has effectively confirmed back ground radiation from matter expelled out of our light radius stars spin axis into their star forming Fermi bubbles, the material ejected is in the same form as the original 15billion year old primordial soup emitting the same background radiation to this present day in our galaxies where our light radius stars reside.
SkyLight
5 / 5 (9) Jun 12, 2018
@RC - skulking here in this forum for years trying to get others HERE to accept his views. But he knows very well that nobody in academia - "mainstream" if you will - would give his ideas more than a moment's perusal before they chuck them in the garbage for the unschooled, half-arsed nonsense that they are. They'd do the same with his monumentally inane TOE if ever he had the cojones to publish it.

So, he haunts this forum, his Dunning-Kruger leading him to believe that he is so especially gifted and scientifically literate that he can point out all the glaring mistakes made by all those stupid PhDs and professors in the mainstream.

But in reality (check that out, RC), he's like a dirty old man in a shabby raincoat, groping at forum visitors as they pass by, whispering "mate" and "g'day" in their ears as if he were their buddy. Just amazing how desperate some people are to get attention.
granville583762
2.6 / 5 (5) Jun 12, 2018
Leave that poor mole alone Skylight, it's suffered enough
SkyLight! you paint a sad lonely picture of commentators like yourself grasping at straws on where to get the ideas from to achieve that rarity of species, a Nobel Prize, when in reality the trees are dripping with Nobel Prize winning ideas.
When you enter this site the ideas just ooze out you're finger tips, the very pores of your skin ooze ideas.
You just do not need to make any effort at all; they come so effortlessly you just do not have time to whack moles as all your time is used up inkly typing them down.
Give it a try SkyLight and leave that poor mole alone, it's suffered enough
SkyLight
5 / 5 (7) Jun 12, 2018
@granville, I think the only thing that's oozing round here are the last few intact brain-cells escaping the black horror within your head by slipping silently out of your ears. Soon it will be all black, and you will be at peace.
RNP
5 / 5 (5) Jun 12, 2018
@granville583762
Your should know that your use of sock-puppets to promote your scores is obvious to people that use this site. Not that it matters. Everybody with any scientific knowledge will easily identify you as a crank.
granville583762
1 / 5 (2) Jun 12, 2018
Rating is for excellence not for frivolous comments
RNP@granville583762
Your should know that your use of sock-puppets to promote your scores is obvious to people that use this site. Not that it matters. Everybody with any scientific knowledge will easily identify you as a crank.

If we disreguard the fact this does not count as a coment, have you not got what you have just described'
based on your comment as your experiencing it your self, as you describe it sock puppets why use the rating system as it is obviously not working as your observation should not have been rated.
granville583762
1 / 5 (2) Jun 12, 2018
The rating system RNP as you rightly point out is not to down grade comments, it is also being used as a form of silent commenting, instead of inkly typing your thoughts on what you think of others comments come out with it and say it instead of clicking the rating star.
We all know it does not mean any thing any more so why use it -
Thanks for pointing out the pointlessnes of the rating system RNP!
granville583762
1 / 5 (2) Jun 12, 2018
SkyLight> @granville, I think the only thing that's oozing round here are the last few intact brain-cells escaping the black horror within your head by slipping silently out of your ears. Soon it will be all black, and you will be at peace.

Well from a Skylight that appropiate!
granville583762
1 / 5 (2) Jun 12, 2018
SkyLight> @granville, I think the only thing that's oozing round here are the last few intact brain-cells escaping the black horror within your head by slipping silently out of your ears. Soon it will be all black, and you will be at peace.

Well from a Skylight that appropiate!

And there you are RNP, Skylight no need to use the obsolete rating system
granville583762
1 / 5 (2) Jun 12, 2018
Biting the hand that feeds you
RNP> @granville583762
Your should know that your use of sock-puppets to promote your scores is obvious to people that use this site. Not that it matters. Everybody with any scientific knowledge will easily identify you as a crank.

I like how you describe your rating benefacactors RNP, between your self and Skylight you have called on the servics as you describe them " 9 sock puppets" RNP!
RealityCheck
1 / 5 (4) Jun 12, 2018
@RNP.

That sort of biased kneejerking and refusal to actually listen and learn resulted in 'egg on faces' among the same gang of bot-voting mainstream defenders/parrots during the Bicep2 fiasco; when that gang were attacking the messenger (me) instead of actually listening and thinking for themselves as I suggested according to scientific method principles.

It appears that few if any of that same gang have learned their lesson from their Bicep2 fiasco; and still pursue personal agendas/vendettas instead of listening and learning.

Anyhow, to give you an idea how 'ahead of the curve' I've been in cosmology theory/comprehension, and how 'uninformed and erroneous' your opinion and assessment is of me/my work, go read this novel (for mainstream) gravitational theory article (alas they still haven't got it anywhere near correct/complete as I have):

https://arxiv.org...3155.pdf

Attentive longstanding members of PO will know what I'm talking about. :)
SkyLight
5 / 5 (4) Jun 12, 2018
Attentive longstanding members of PO will know...
how fixated @RC is on his own vastly over-inflated sense of superiority and invincibility. Sad...
RealityCheck
1 / 5 (3) Jun 13, 2018
@Skylight.
Attentive longstanding members of PO will know...
how fixated @RC is on his own vastly over-inflated sense of superiority and invincibility. Sad...
So says a longstanding member of the same bot-voting troll gang that has been infesting/sabotaging science discourse on the net science forums for years. :)

@SkyLight, maaaate, your continuing interruptions and science-empty posts, especially that above, merely betrays your lack of original thought and even greater lack of useful contributions to discussion of the substantive science points/issues being discussed. And your 'need' to be such a useless troll against your betters in science-comprehension on the internet science forums, and your 'need' to 'join a gang' of bot-voting ninnies, strongly indicates your 'need' to 'cover and compensate' for a rampant 'inferiority complex' which drives you to such malice and irrelevance.

Anyhow, RNP asked; I provided. You missed that important fact, troll. :)

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