Oort clouds around other stars should be visible in the cosmic microwave background

Oort clouds around other stars should be visible in the cosmic microwave background
The layout of the solar system, including the Oort Cloud, on a logarithmic scale. Credit: NASA

For decades, scientists have theorized that beyond the edge of the solar system, at a distance of up to 50,000 AU (0.79 ly) from the sun, there lies a massive cloud of icy planetesimals known as the Oort Cloud. Named in honor of Dutch astronomer Jan Oort, this cloud is believed to be where long-term comets originate from. However, to date, no direct evidence has been provided to confirm the Oort Cloud's existence.

This is due to the fact that the Oort Cloud is very difficult to observe, being rather far from the sun and dispersed over a very large region of space. However, in a recent study, a team of astrophysicists from the University of Pennsylvania proposed a radical idea. Using maps of the Cosmic Microwave Background (CMB) created by the Planck mission and other telescopes, they believe that Oort Clouds around other stars can be detected.

The study – "Probing Oort around Milky Way stars with CMB surveys", which recently appeared online – was led by Eric J Baxter, a Ph.D. student from the Department of Physics and Astronomy at the University of Pennsylvania. He was joined by Pennsylvania professors Cullen H. Blake and Bhuvnesh Jain (Baxter's primary mentor).

To recap, the Oort Cloud is a hypothetical region of space that is thought to extend from between 2,000 and 5,000 AU (0.03 and 0.08 ly) to as far as 50,000 AU (0.79 ly) from the sun – though some estimates indicate it could reach as far as 100,000 to 200,000 AU (1.58 and 3.16 ly). Like the Kuiper Belt and the Scattered Disc, the Oort Cloud is a reservoir of trans-Neptunian objects, though it is over a thousands times more distant from our sun as these other two.

Credit: Universe Today

This cloud is believed to have originated from a population of small, icy bodies within 50 AU of the sun that were present when the solar system was still young. Over time, it is theorized that orbital perturbations caused by the caused those objects that had highly-stable orbits to form the Kuiper Belt along the ecliptic plane, while those that had more eccentric and distant orbits formed the Oort Cloud.

According to Baxter and his colleagues, because the existence of the Oort Cloud played an important role in the formation of the solar system, it is therefore logical to assume that other star systems have their own Oort Clouds – which they refer to as exo-Oort Clouds (EXOCs). As Dr. Baxter explained to Universe Today via email:

"One of the proposed mechanisms for the formation of the Oort cloud around our sun is that some of the objects in the protoplanetary disk of our solar system were ejected into very large, elliptical orbits by interactions with the giant planets. The orbits of these objects were then affected by nearby stars and galactic tides, causing them to depart from orbits restricted to the plane of the solar system, and to form the now-spherical Oort cloud. You could imagine that a similar process could occur around another star with giant planets, and we know that there are many stars out there that do have giant planets."

As Baxter and his colleagues indicated in their study, detecting EXOCs is difficult, largely for the same reasons for why there is no direct evidence for the solar system's own Oort Cloud. For one, there is not a lot of material in the cloud, with estimates ranging from a few to twenty times the mass of the Earth. Second, these objects are very far away from our sun, which means they do not reflect much light or have strong thermal emissions.

Credit: Universe Today

For this reason, Baxter and his team recommended using maps of the sky at the millimeter and submillimeter wavelengths to search for signs of Oort Clouds around other stars. Such maps already exist, thanks to missions like the Planck telescope which have mapped the Cosmic Microwave Background (CMB). As Baxter indicated:

"In our paper, we use maps of the sky at 545 GHz and 857 GHz that were generated from observations by the Planck satellite. Planck was pretty much designed *only* to map the CMB; the fact that we can use this telescope to study exo-Oort clouds and potentially processes connected to planet formation is pretty surprising!"

This is a rather revolutionary idea, as the detection of EXOCs was not part of the intended purpose of the Planck mission. By mapping the CMB, which is "relic radiation" left over from the Big Bang, astronomers have sought to learn more about how the universe has evolved since the the early universe – circa. 378,000 years after the Big Bang. However, their study does build on previous work led by Alan Stern (the principal investigator of the New Horizons mission).

In 1991, along with John Stocke (of the University of Colorado, Boulder) and Paul Weissmann (from NASA's Jet Propulsion Laboratory), Stern conducted a study titled "An IRAS search for extra-solar Oort clouds". In this study, they suggested using data from the Infrared Astronomical Satellite (IRAS) for the purpose of searching for EXOCs. However, whereas this study focused on certain wavelengths and 17 star systems, Baxter and his team relied on data for tens of thousands of systems and at a wider range of wavelengths.

Oort clouds around other stars should be visible in the cosmic microwave background
All-sky data obtained by the ESA’s Planck mission, showing the different wavelenghts. Credit: ESA

Other current and future telescopes which Baxter and his team believe could be useful in this respect include the South Pole Telescope, located at the Amundsen–Scott South Pole Station in Antarctica; the Atacama Cosmology Telescope and the Simons Observatory in Chile; the Balloon-borne Large Aperture Submillimeter Telescope (BLAST) in Antarctica; the Green Bank Telescope in West Virgina, and others.

"Furthermore, the Gaia satellite has recently mapped out very accurately the positions and distances of stars in our galaxy," Baxter added. "This makes choosing targets for exo-Oort cloud searches relatively straightforward. We used a combination of Gaia and Planck data in our analysis."

To test their theory, Baxter and is team constructed a series of models for the thermal emission of exo-Oort clouds. "These models suggested that detecting exo-Oort clouds around nearby stars (or at least putting limits on their properties) was feasible given existing telescopes and observations," he said. "In particular, the models suggested that data from the Planck satellite could potentially come close to detecting an exo-Oort cloud like our own around a nearby star."

In addition, Baxter and his team also detected a hint of a signal around some of the stars that they considered in their study – specifically in the Vega and Formalhaut systems. Using this data, they were able to place constraints on the possible existence of EXOCs at a distance of 10,000 to 100,000 AUs from these stars, which roughly coincides with the distance between our sun and the Oort Cloud.

Oort clouds around other stars should be visible in the cosmic microwave background
The relative sizes of the inner Solar System, Kuiper Belt and the Oort Cloud. Credit: NASA, William Crochot

However, additional surveys will be needed before the existence any of EXOCs can be confirmed. These surveys will likely involve the James Webb Space Telescope, which is scheduled to launch in 2021. In the meantime, this study has some rather significant implications for astronomers, and not just because it involves the use of existing CMB maps for extra-solar studies. As Baxter put it:

"Just detecting an exo-Oort cloud would be really interesting, since as I mentioned above, we don't have any direct evidence for the existence of our own Oort cloud. If you did get a detection of an exo-Oort cloud, it could in principle provide insights into processes connected to planet formation and the evolution of protoplanetary disks. For instance, imagine that we only detected exo-Oort clouds around that have giant planets. That would provide pretty convincing evidence that the formation of an Oort cloud is connected to giant planets, as suggested by popular theories of the formation of our own Oort cloud."

As our knowledge of the universe expands, scientists become increasingly interested in what our solar system has in common with other star systems. This, in turn, helps us to learn more about the formation and evolution of our own system. It also provides possible hints as to how the universe changed over time, and maybe even where life could be found someday.


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A new object at the edge of our Solar System discovered

More information: Probing Oort clouds around Milky Way stars with CMB surveys. arxiv.org/pdf/1808.00415.pdf
Citation: Oort clouds around other stars should be visible in the cosmic microwave background (2018, August 16) retrieved 22 May 2019 from https://phys.org/news/2018-08-oort-clouds-stars-visible-cosmic.html
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Aug 20, 2018
@RNP (and rest of @Forum).

Finally we have mainstream scientists actually looking for CMB emissions from cosmic processes/materials existing NOW; having nothing to do with all those exclusive-to-BB/Inflation attributions, interpretations and 'explanations'.

As I have been trying to inform you, @RNP, during our most recent exchanges re CMB and its ongoing sources not needing BB etc; in threads:

https://phys.org/...ary.html

https://phys.org/...ark.html

So, mate, everyone, about time to cease all the kneejerking to denial/insults whenever I point out things which you/mainstream is just now becoming aware of, that makes previously alleged BB/Inflation 'supporting evidence' etc claims/interpretations moot, hey?

Try to chill out, listen, rethink from now on, as scientific method dictates; and drop lose past animosities, biases which formed at a time when even mainstream was in the dark and/or on the wrong track. Enjoy Science! :)

Aug 20, 2018
As I have been trying to inform you, @RNP, during our most recent exchanges re CMB and its ongoing sources not needing BB etc; in threads:


Garbage. Which part of the CMB is from OCs? Given that the authors state:

In principle, the thermal emission from the OC imprints a distortion of the black body spectrum of the CMB, but even for optimistic assumptions about the mass of our OC, this signal is too small to be observed with existing CMB experiments (Babich et al. 2007)



Aug 20, 2018
@jonesdave.
As I have been trying to inform you, @RNP, during our most recent exchanges re CMB and its ongoing sources not needing BB etc; in threads:
Garbage. Which part of the CMB is from OCs? Given that the authors state:
In principle, the thermal emission from the OC imprints a distortion of the black body spectrum of the CMB, but even for optimistic assumptions about the mass of our OC, this signal is too small to be observed with existing CMB experiments (Babich et al. 2007)
You can't have it both ways, @jd. I long pointed out that intervening processes/materials attenuate long distance radiation down to CMB spectrum. Now you have further examples of even nearby processes/materials affecting CMB. And you complain about that. I earlier provided @RNP with many examples where CMB wavelength radiation is also produced by ongoing sources/processes which do not depend on any BB etc timeline/interpretation. And you complain about that. Rethinkit. :)

Aug 20, 2018
And you complain about that


No, I merely pointed out that you were tasking crap, as any putative signal from our, or any other Oort cloud, cannot be seen in the current data, and therefore to use it as an argument for the CMB is idiotic.

Aug 20, 2018
A jonesdave reputative argument
jonesdave> No, I merely pointed out that you were tasking crap, as any putative signal from our, or any other Oort cloud, cannot be seen in the current data, and therefore to use it as an argument for the CMB is idiotic.
People thought the earth was flat even though no one had sailed or flown round the earth - because there is not scientific evidence the world is a sphere the world is consequently flat - a jonesdave philosophy in a nut shell, provide the evidence or the world is flat you idiotic EU loon!

Aug 20, 2018
A jonesdave reputative argument
jonesdave> No, I merely pointed out that you were tasking crap, as any putative signal from our, or any other Oort cloud, cannot be seen in the current data, and therefore to use it as an argument for the CMB is idiotic.
People thought the earth was flat even though no one had sailed or flown round the earth - because there is not scientific evidence the world is a sphere the world is consequently flat - a jonesdave philosophy in a nut shell, provide the evidence or the world is flat you idiotic EU loon!


Go away Granny, you are a waste of pixels.

Aug 20, 2018
@jonesdave.
And you complain about that
No, I merely pointed out that you were talking crap, as any putative signal from our, or any other Oort cloud, cannot be seen in the current data, and therefore to use it as an argument for the CMB is idiotic.
The interaction between the material and the radiation must be there to observe any attenuation of CMB passing through that region. Hence CMB is affected by intervening material/processes during long distance transits. Hence not all CMB signals are 'pristine' CMB allegedly traveling unaffected from distant (hypothesized) BB era. So no definite conclusion/claim can be drawn attributing CMB to BB/Inflation etc causes. And I've long given @RNP and others examples of many/ubiquitous cosmic sources/processes 'currently' producing CMB without any connection to or need for any alleged BB, Inflation/expansion hypotheses for its interpretation/explanation re timeline/source/causes. Rethinkit, mate. And chill! :)

Aug 20, 2018
Rethinkit, mate. And chill! :)


No, you rethink it. Consider that you have no relevant qualifications (based on what you come up with) and that far more intelligent and qualified people than you are involved in this work. Why on Earth would I need to rethink anything based on the crap written by some deluded crank on a comments section?
Publish something and maybe I'll read it.

Aug 20, 2018
@jonesdave.
Rethinkit, mate. And chill! :)
No, you rethink it. Consider that you have no relevant qualifications (based on what you come up with) and that far more intelligent and qualified people than you are involved in this work. Why on Earth would I need to rethink anything based on the crap written by some deluded crank on a comments section?
Publish something and maybe I'll read it.
Spoken like a true believer/elitist who is unshakably deferential of old/naive 'authority figures' to the point that he abdicates his critical thinking to said old/naive authority figures instead of listening and thinking for himself. Why are you here, @jd, if you keep kneejerking to denial and insults? Not a good look. Chill. Learn from the scientific/logical observations made by others, irrespective of how 'low' the venue/milieu is in your opinion. There is gems among the dross to be found everywhere you look, mate; it's only a matter of sifting and recognizing. Enjoy. :)

Aug 21, 2018
Learn from the scientific/logical observations made by others,.......


I do. However, for very good reasons, I only listen to people who are qualified to know what they are talking about. This does not include you.

Aug 21, 2018
Present day star forming blackholes create CMB
Considering a blackhole hole; a blackhole ejects 50% of its star snacking out it's spin-axis star forming Fermi-clouds stretching 25,000light years either end of its spin-axis above and below the host galaxy.
The emanating matter emerging is the same form of matter as the proposed primordial blackhole of creation which emanated CMB - consequently these present day star forming blackhole are emanating exactly the same matter produce CMB

P.S. Jonesdave assessment on theories when concerning lack of evidence - ******There is no evidence to prove the proposed primordial blackhole of creation produced CMB – go away you idiotic CMB loon, where is your evidence, prove this mythical primordial blackhole of creation, how does it emanate CMB – yeah you can't go away CMB loon, you're a waste of pixels…

Aug 21, 2018
^^^^^^^Mentally deranged. Has to be.

Aug 21, 2018
jonesdave describing his own words as mentally deranged
^^^^^^^Mentally deranged. Has to be.

J.D this is what your words sound like to the public at large, now It was your good self that described a parody on your own words as deranged, so there is hope for you still.

Aug 21, 2018
jonesdave describing his own words as mentally deranged
^^^^^^^Mentally deranged. Has to be.

J.D this is what your words sound like to the public at large, now It was your good self that described a parody on your own words as deranged, so there is hope for you still.


No, you f***wit, YOU are mentally deranged. Need me to spell it out? Oh, I did! Now p*ss off, you waste of space.

Aug 21, 2018
From those meteor days to this present day not one expletive has passed my lips jonesdave, if you remember correctly you were leaving searching meteor requests in those hazy lazy days and I'm exactly the same to this present day, so what gives J.D. if you think on J.D, you will recall one of your logical fiends gave you some friendly advice.

Aug 21, 2018
From those meteor days to this present day not one expletive has passed my lips jonesdave, if you remember correctly you were leaving searching meteor requests in those hazy lazy days and I'm exactly the same to this present day, so what gives J.D. if you think on J.D, you will recall one of your logical fiends gave you some friendly advice.


And I'm giving you some friendly advice; bugger off, you are scientifically illiterate, you are not funny, you are not clever, and your presence here contributes precisely nothing.

Aug 22, 2018
The Ort Cloud – where's your evidence
Jan Hendrik Oort a Dutch astronomer who made significant contributions to the understanding of the Milky Way and who was a pioneer in the field of radio astronomy.
The Oort cloud a theoretical cloud of icy planetesimal's proposed to surround the Sun from 0.8 to 3.2 ly is in two regions a disc-shaped inner Oort cloud and a spherical outer Oort cloud.
The Oort clouds outer limit defines the cosmographical boundary of the Solar System and the extent of the Sun's Hill sphere - https://en.wikipe...rt_cloud
For Decades, scientists theorized beyond 0.79 ly from the sun lies a cloud of icy planetesimal's where long-term comets however, to date, no direct evidence has been provided to confirm the Oort Coud's existence
The key relevant point for all those of logical mind in the club of golden stars - to date, there is no evidence to confirm the Oort Cloud's existence.

Aug 22, 2018
What would be really interesting is for humy to show up & explain why all this interstellar dust does not create FRICTION, thus promoting his theories for frictionless MOMENTUM between the stars & galaxies.

> humy: Jonsey desperately needs your help, you can tell by the quantity of foul mouthed expletives he's been producing that he's run out of ideas, he's floundering around in a sea of pure Pop-Cosmology psycho-babble & can't figure out how to extricate himself from it.

>RC et al: There is still another finding by the New Horizons spacecraft,now out beyond the orbit of Pluto, that has uncovered "A Wall of Hydrogen" at the edge of the solar system. I'm dismayed that PhysOrg still has not picked up on the finding, it's over a week old by now. This will further traumatize the Pop-Cosmology aficionados & their beliefs it is clear & open sailing between stars & galaxies.

Aug 22, 2018
Benni the Straw Man!

Aug 22, 2018
Benni the Straw Man!


Ignore him, he's too thick for words!

Aug 22, 2018
Benni the Straw Man!


Ignore him, he's too thick for words!


Jonsey desperately needs your help, you can tell by the quantity of foul mouthed expletives he's been producing that he's run out of ideas, he's floundering around in a sea of pure Pop-Cosmology psycho-babble & can't figure out how to extricate himself from it.
Now Ojo adds his name calling rants into the mix.......hey, either of you two guys been working on any Differential Equations the last few days? Been noticing how Real Science has been displacing your DM Cosmic Fairy Dust & you're getting all bent out of shape about it aren't you? Well that's Real Science for you, it can drag ludicrous hypotheses out into the cold cruel light of day & destroy the most favored fantasies........I know, you two will simply followup with more name calling rants




Aug 22, 2018
Differential Equations the last few days? Been noticing how Real Science has been displacing your DM Cosmic Fairy Dust & you're getting all bent out of shape about it aren't you?


You can't do differential equations. You can't even do basic maths. As proven. And what real science is this? Link me to the paper/s. Otherwise, didn't happen.

Aug 22, 2018
Learn from the scientific/logical observations made by others,.......


I do. However, for very good reasons, I only listen to people who are qualified to know what they are talking about. This does not include you.


No you don't. If it's Pop-Cosmology you're into it heart, soul, & mind, and all Pop-Cosmology is about Perpetual Motion & defying every immutable law of physics that exists & you walk down that sawdust trail everytime you come into this chatroom with your perpetual motion theories.

Aug 22, 2018
No you don't.


Yes, I do. I just don't listen to dipshits like you, and others, who are too thick to understand science. If you knew anything about science, and had valid objections, they should be easy to find in the scientific literature. Yet they don't seem to exist. And why would anybody listen to a loon like you on a comments section of a science news aggregate?

Aug 22, 2018
The theory and the existence – where's your evidences, you have none so it does not exist.
If there is no indisputable evidence the Ort cloud actually exists and theoreticians theorising the existence of the Ort cloud had to produce concrete evidence and sources based on the present evidence or lack of present evidence there could be no articles written on the existence of an Ort cloud
This would result in the now well worn argument - where's the evidence there is none, so there can be no Ort cloud
Based on a argument if there's no evidence there can be not what theoreticians theorise, what is the point of theorising the Ort cloud as this is an example of theorising what presently cannot be proved to exist – based on this philosophy if we could never external view the earth – the earth would still be presently flat.

Aug 22, 2018
^^^^^^Of course it is theoretical. That is why people are coming up with suggestions as to how we might detect one. As for evidence, the orbits of many long term comets have been measured since the time of Edmund Halley, and they show that they originate at the distances theorised for the Oort Cloud.
I would suggest reading the science behind the hypothesis before commenting on it.

Aug 22, 2018
^^^^^^Of course it is theoretical. That is why people are coming up with suggestions as to how we might detect one. As for evidence, the orbits of many long term comets have been measured since the time of Edmund Halley, and they show that they originate at the distances theorised for the Oort Cloud.
I would suggest reading the science behind the hypothesis before commenting on it.

This is infinitely better

Aug 22, 2018
Is this a new start or just an illusion?
^^^^^^Of course it is theoretical. That is why people are coming up with suggestions as to how we might detect one. As for evidence, the orbits of many long term comets have been measured since the time of Edmund Halley, and they show that they originate at the distances theorised for the Oort Cloud.
I would suggest reading the science behind the hypothesis before commenting on it.

This is infinitely better

This is infinitely better jonesdave in that there is not an expletive in sight

Aug 22, 2018

This is infinitely better jonesdave in that there is not an expletive in sight


So why the f*ck didn't you know this? Huh? Stop commenting on sh*t that is beyond your understanding. Yes?

Aug 22, 2018
The illusionary conformation
This is infinitely better jonesdave in that there is not an expletive in sight


So why the f*ck didn't you know this? Huh? Stop commenting on sh*t that is beyond your understanding. Yes?

The conformation of illusion is truly an illusion of epic expletives

Aug 22, 2018
The illusionary conformation
This is infinitely better jonesdave in that there is not an expletive in sight


So why the f*ck didn't you know this? Huh? Stop commenting on sh*t that is beyond your understanding. Yes?

The conformation of illusion is truly an illusion of epic expletives


Can't answer the question, eh, woo boy? Why did you not know this high school science? Thick? Methinks.

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