Every time we develop new tech for studying this universe, we find something new. New to us, that is.
This week, I’ll be talking about unexpected Jupiter-size objects in the Orion Nebula, and why scientists at CERN dropped a few hundred antihydrogen atoms.
- Baffling Binaries, Planetary Problem: JuMBOs in Orion
- Antimatter, Gravity, the Universe: and an Experiment at CERN
- Ptolemy, C. S. Lewis, Cosmic Scale, and Assumptions
Baffling Binaries, Planetary Problem: JuMBOs in Orion
“James Webb telescope makes ‘JuMBO’ discovery of planet-like objects in Orion“
Jonathan Amos, BBC News (October 2, 2023)“Jupiter-sized ‘planets’ free-floating in space, unconnected to any star, have been spotted by the James Webb Space Telescope (JWST).
“What’s intriguing about the discovery is that these objects appear to be moving in pairs. Astronomers are currently struggling to explain them.
“The telescope observed about 40 pairs in a fabulously detailed new survey of the famous Orion Nebula.
“They’ve been nicknamed Jupiter Mass Binary Objects, or ‘JuMBOs’ for short….”
For some reason, the first thing that jumped out at me in this article was “about 40 pairs”.
Giving a approximate number might mean that the reporter lost his notes and couldn’t remember how many pairs the scientists had found. Or maybe the scientists weren’t sure how many JuMBOs they’d spotted.
Or, much more likely, someone at BBC News decided that “about 40 pairs” was more appropriate for the article. Possibly because the exact number wasn’t as important as the fact that scientists said they had found “about 40 pairs”.
At any rate, I kept reading the article. Then I did a little checking.
Eventually, I learned that two scientists have found 42 pairs of (very) roughly Jupiter-mass objects in the Trapezium Cluster. And that they called them JuMBOs.
A quick glance at their pre-publication paper’s Table 1 showed that the JuMBOs ranged from 0.0006 to 0.012 solar masses. Jupiter’s mass is just under 0.001 solar mass, so calling them Jupiter Mass Binary Objects, or JuMBOs, makes sense.
And that’s another example, I think, of how much less stuffy scientists have become in the decades since I started paying attention. I mean to say: JuMBOs? Quarks? This isn’t your starched-collar 19th century science, and that’s another topic.1
Low Expectations, a Pleasant Surprise
I’ve got low expectations when it comes to “science news” in unfamiliar sources: and many familiar sources, for that matter.
So I was pleasantly surprised when my news feed showed only one apparently-overstated headline.
“NASA’s Webb ‘breaks physics’ with ‘JuMBO’ discovery of new astronomical objects“
Ian Randall, Daily Express US (October 2, 2023)“Researchers using NASA’s James Webb Space Telescope may have discovered a new class of astronomical objects that defy current theories of planet and star formation….”
I was even more pleasantly surprised at the job Ian Randall did, discussing this week’s JuMBO paper. He includes details I don’t remember seeing in the BBC News piece.
That said, physics isn’t broken, although some aspects of it will need revision. Probably. That’s what “the European Space Agency’s (Esa) senior science adviser told BBC News”.
“…Gas physics suggests you shouldn’t be able to make objects with the mass of Jupiter on their own, and we know single planets can get kicked out from star systems. But how do you kick out pairs of these things together? Right now, we don’t have an answer. It’s one for the theoreticians,’ the European Space Agency’s (Esa) senior science adviser told BBC News….”
(“James Webb telescope makes ‘JuMBO’ discovery of planet-like objects in Orion“, Jonathan Amos, BBC News (October 2, 2023))
[emphasis mine]
ESA’s senior science advisor is very likely right about that.
After reading that bit from the BBC News article, I wondered who ESA’s senior science advisor was, and what connection — if any — he had with the recently-published research.
So I Googled ‘ESA senior science advisor’, learned the name was Mark McCaughrean, checked his online profiles, and saw that he co-authored that study.
That establishes both his connection with the research and his qualifications for commenting on its probable impact on gas physics.
Which is good news, but it took time to learn — or confirm, if Professor McCaughrean’s ESA position should have been obvious — that “the … senior science advisor” and one of the paper’s authors were the same person.
Sorry about venting: it’s been one of those weeks, and I’ll leave it at that. Anyway, back to Professor McCaughrean, JuMBOs (Jupiter Mass Binary Objects), and PMOs (Planetary Mass Objects).
He and Samuel G. Pearson found that 9% of the PMOs they spotted in the Trapezium Cluster were binaries: double planets. Well, double objects.2
Whether those roughly-Jupiter-mass objects are “planets” will depend on who’s talking.
A Planet by Any Other Name
The Solar System has nine, eight, or 10 planets: depending on whether or not I count Ceres and Pluto.
I talked about planets and how “planet” has been defined back in April, so I’ll be brief. Brief for me, that is.
The International Astronomical Union (IAU) says that a “planet” is something that:
- Orbits our star: the Sun
- Is massive enough for gravity to pull it into roughly spherical shape
- Has “cleared the neighbourhood” around its orbit
The third item excludes Ceres and Pluto, which the IAU reclassified as dwarf planets back in 2006. Last I heard, the 2006 IAU definition of “planet” is still debatable and debated.
A problem I have with the current IAU definition is that it excludes all 5,000 or so objects with planetary mass we’ve catalogued to date that don’t orbit our star.
I can see practical reasons for having one word for a particular sort of object in the Solar System, and another for similar objects elsewhere. For one thing, we can send robots to the Solar System “planets”, while “exoplanets” are still out of range.
But making the distinction strikes me as a trifle silly.
It’s as if the Royal Astronomical Society defined largish watercourses in England as “rivers”, and similar watercourses elsewhere “exorivers”. Their counterparts in Canada and New Zealand might debate the definition, and that’s yet another topic.
One more thing. The International Union of Geological Sciences (IUGS) definitions of “planet” include exoplanets. And it’s definitions. Plural.
If I’m going to keep this brief, I’d better put distinctions between brown dwarfs and gas giants on hold, at least for now.3
JuMBOs and Questions
I figure that Pearson and McCaughrean’s paper will spark lively debate: and more study of planetary systems forming in the Orion Nebula.
That’s because what they found may suggest that the line between “planet” and “star” isn’t so much a line as it is a zone.
“Jupiter Mass Binary Objects in the Trapezium Cluster“
Samuel G. Pearson, Mark J. McCaughrean; European Space Research and Technology Centre (ESTEC), European Space Agency (ESA) (October 2, 2023) via arXiv“Abstract
“A key outstanding question in star and planet formation is how far the initial mass function of stars and sub-stellar objects extends, and whether or not there is a cut-off at the very lowest masses. Isolated objects in the planetary-mass domain below 13 Jupiter masses, where not even deuterium can fuse, are very challenging to observe as these objects are inherently faint. Nearby star-forming regions provide the best opportunity to search for them though: while they are young, they are still relatively warm and luminous at infrared wavelengths. Previous surveys have discovered a handful of such sources down to 3-5 Jupiter masses, around the minimum mass limit established for formation via the fragmentation of molecular clouds, but does the mass function extend further? In a new James Webb Space Telescope near-infrared survey of the inner Orion Nebula and Trapezium Cluster, we have discovered and characterised a sample of 540 planetary-mass candidates with masses down to 0.6 Jupiter masses, demonstrating that there is indeed no sharp cut-off in the mass function. Furthermore, we find that 9% of the planetary-mass objects are in wide binaries, a result that is highly unexpected and which challenges current theories of both star and planet formation.…”
[emphasis mine]
At the very least, scientists will be developing new models for planetary formation.
I doubt that we’ll see something other than the nebular hypothesis as the best — or least-unlikely — model for planetary system formation. But finding so many roughly Jupiter-mass objects in pairs means that details of the nebular hypothesis need revision.
Binary stars are common. So are binary asteroids. Binary planets — I think we’re living on one, but thinking of the Earth-Moon system as a binary is still a hard sell in some circles.
With binary stars, we’ve learned that there’s a link between mass and being in a binary system. Massive stars are more likely to be binaries than low-mass ones.
We’ve recently learned that planets can be tossed away from their stars in a planetary system’s early years, when planets are still settling into moderately stable orbits.
But, as Professor McCaughrean and others have said, we don’t have a model for how a pair of Jupiter-mass objects could get tossed into the void between stars.
Maybe those JuMBOs didn’t get thrown out of their planetary systems. Maybe they formed the way binary stars do: from a collapsing molecular cloud.4
But if they formed in roughly the same way low-mass double stars form, then we need explanations for how there are so many in the Trapezium Cluster.
Again, I suspect that distinctions between “gas giant planet” and “star” at the very least need re-examination.
Antimatter, Gravity, the Universe: and an Experiment at CERN
“ALPHA experiment at CERN observes the influence of gravity on antimatter“
Physics, News, CERN (September 27, 2023)“Isaac Newton’s historic work on gravity was apparently inspired by watching an apple fall to the ground from a tree. But what about an ‘anti-apple’ made of antimatter, would it fall in the same way if it existed? According to Albert Einstein’s much-tested theory of general relativity, the modern theory of gravity, antimatter and matter should fall to Earth in the same way. But do they, or are there other long-range forces beyond gravity that affect their free fall?
“In a paper published today in Nature, the ALPHA collaboration at CERN’s Antimatter Factory shows that, within the precision of their experiment, atoms of antihydrogen — a positron orbiting an antiproton — fall to Earth in the same way as their matter equivalents….”
Well, of course antimatter falls down!! Everybody knows that everything falls down! Wasting money on some scientifical shenanigans! Money that should have been spent on something useful: like filling potholes here in Minnesota.
No, I don’t see the CERN experiment that way. Although potholes are a perennial problem in my part of the world.
On the other hand, I’m mildly surprised that CERN’s latest antimatter experiment hasn’t inspired headlines like ‘Scientists Seek God Particle’ and “Collider Triggers End-of-World Fears“.
Still, coverage could have been worse. Take this Times article, for example.
“Collider Triggers End-of-World Fears“
Eben Harrell, Time (September 24, 2008) via Internet Archive Wayback Machine“From the flagellants of the Middle Ages to the doomsayers of Y2K, humanity has always been prone to good old-fashioned the-end-is-nigh hysteria. The latest cause for concern: that the earth will be destroyed and the galaxy gobbled up by an ever-increasing black hole next week….”
Good news, Time didn’t endorse that particular crisis du jour. Not-so-good news, the headline invoked “End-of-World Fears”.
In a way, I don’t blame science editors for deadpan reporting of doomsday predictions.
Their job is generating content that gets attention: and advertising revenue. Convincing readers that their lives, nay, this very Earth, are in deadly peril — or at least inspiring trepidation regarding newfangled science — might seem like a good idea.
It hasn’t done wonders for my opinion of mainstream media, but I don’t subscribe to The Times, The Guardian, or other shining beacons of — whatever it is they uphold.
Again, sorry about venting. I’ve had a frustrating time, trying to find background on the CERN antimatter experiment. Detailed background. If Nature wasn’t behind a paywall — well, “if wishes were horses, beggars would ride”.
I’m just glad services like arXiv exist, and allow access to folks like me.5
A Quick Look at Antimatter, From Hicks to Dirac, and Weirdness
The idea that negative matter might exist goes back at least to the 1880s, when William Hicks said matter with negative gravity was possible. If I start talking about the vortex theory of gravity and aether, then I’ll still be writing this thing when Saturday rolls around.
In 1898, Arthur Schuster used the word “antimatter” in two letters to Nature. I gather they weren’t entirely serious, but he did speculate that his “antimatter” and ordinary matter might annihilate each other. And that his “antimatter” would have negative gravity.
But, apart from the name, Schuster’s antimatter had little to do with what scientists at CERN have been studying.
Current ideas of antimatter go back to “The Quantum Theory of the Electron“, Paul Adrien Maurice Dirac, Proceedings of the Royal Society A (February 1, 1928).
Since then, most scientists figure antimatter and gravity interact pretty much the way ordinary matter and gravity do.
Things get — complicated — after that.
And a bit weird, including treating negative energy modes of the electron field as if they’re going backward in time.6
The point is that, although most scientists were pretty sure that antimatter would fall down, nobody had proven that this was true. And some of the math describing how antimatter works is distinctly non-intuitive.
(Most) Antihydrogen Atoms Fell Down
I had been looking for discussions of how CERN makes antihydrogen atoms, but didn’t find a photo of their antiproton decelerator until late Thursday afternoon.
That page on the CERN site was more a backgrounder than a detailed description; so I’ll just rephrase what I found in that BBC News piece, and in CERN press releases.
The folks at CERN sent antiprotons and positrons — particles that are like electrons, but have a positive charge — streaking along “pipes” at just under the speed of light.
When the two streams reached the experiment area, the antiprotons and positrons were slowed down to more manageable speeds, mixed, and stored in a confinement container.
Just how that works, I don’t know. That’s why I was looking for more detailed discussions.
I gather that the confinement device is a Penning trap: a sort of magnetic bottle for charged particles. Or, in this case, anthydrogen atoms.
Going mostly from what I read in the CERN press releases, scientists trapped antihydrogen atoms in their Penning trap, in seven batches of about 100 each. Each time they had a batch, they released it over a period of 20 seconds.
They’d run computer simulations for what would happen to hydrogen atoms, the sort with proton nuclei and one electron, under those conditions. The simulations showed 20% flying out the top of the trap, 80% dropping out the bottom.
That’s what how the antihydrogen atoms acted, too.
This is a very strong indication that antihydrogen interacts with gravity the way normal matter does.
That’s not, however, the end of this research. Scientists at CERN can’t be sure that antihydrogen falls at the same rate as normal matter. That’s something they’ll be testing, when they develop more precise instruments.7
Mystery of the Missing Antimatter
Antimatter, the sort studied at CERN, happens naturally whenever we have high-energy particle collisions: when cosmic rays hit Earth’s atmosphere, for example.
There’s a disaster movie plot lurking there, along the lines of “Cosmic Monsters Meet 2012”, and that’s yet again another topic.
These extremely tiny amounts of antimatter routinely form, touch ordinary matter, and then both disappear in a (tiny) flash of gamma rays.
But apart from those ephemeral bits of antimatter, our part of the universe is pretty much all ordinary matter. Except for dark matter and dark energy and that’s a whole mess of topics I’ll leave for another time.
Our neighborhood being 100% matter is good for us, considering how much energy would get released if antimatter existed locally in visible quantities.
But it’s a serious problem for theoretical physicists and cosmologists. Various flavors of the Big Bang theory are still the best fit with observed phenomena.
Which reminds me: Big Bang theory isn’t the only cosmological model around.
Someone’s probably still supporting plasma cosmology, for example. It says the universe has always been and always will be, cycling between being big and small. Only problem is, plasma cosmology doesn’t fit observed phenomena.
Big Bang models fit observed phenomena: except for the notable lack of local antimatter.
There should be about equal amounts of matter and antimatter around. But there isn’t. Apparently.
Quite a few explanations have been suggested.
One is that this universe has some regions that are (almost) all matter, others that are (almost) all antimatter. If this is so, we could observe gamma radiation generated at boundaries between the regions. Astronomers have looked.
There aren’t any such boundaries in our part of this galaxy.8
‘Where’s the Antimatter?’ — Broadening the Search
But there’s much more to this universe than the Milky Way Galaxy.
Our Milky Way and the Andromeda Galaxy are the two major galaxies in the Local Group, a set of galaxies about 10,000,000 light-years across.
The Local Group is part of the Virgo Supercluster, which may in turn be part of the Laniakea Supercluster. Never mind the size of those things.
At some point, from a human perspective, things are simply “big”. Or, in this case, cosmic.
Maybe astronomers will map gamma ray emitting boundaries between parts of the Virgo Supercluster, or between neighboring superclusters. That would would at least hint that we’re looking at a matter-antimatter boundary.
Or maybe matter and antimatter domains are at a larger scale. That could answer the ‘where’s the antimatter’ question.
But it might also give cosmologists the sort of problems they have explaining things like The Giant Arc: a feature that’s around 3,300,000,000 light-years across.
That’s too big. According to the cosmological principle.9
The cosmological principle, the idea that at large scales this universe looks the same to everyone, has been a pretty good match with observed reality since Newton’s day.
Then, recently, we stated noticing things like the Giant Arc. My guess is that we’re in the process of leaning something new about this universe. Several somethings, most likely.
Ptolemy, C. S. Lewis, Cosmic Scale, and Assumptions
It’s been a few years since I saw ‘Christians believe Earth is flat’ in a chat.
Partly, I figure, because I’m not all that active on social media.
But I’d be pleasantly surprised if similar assumptions regarding Christians, Christianity, and science have finally faded.
“Earth 2.0: Bad News for God“
Jeff Schweitzer, Huffington Post (July 23, 2015)
“…Let us be clear that the Bible is unambiguous about creation: the earth is the center of the universe, only humans were made in the image of god, and all life was created in six days. All life in all the heavens. In six days….”
I’ve been talking about stars and planets in the Orion Nebula, a massive interstellar cloud some 1,350 light-years — drat! I forgot something: and that will wait for another time.
Anyway, I’ve been talking about stars so distant that their light takes more than a millennium to reach us. And galaxy clusters that are many orders of magnitude bigger.
Maybe it’s time for me to try explaining why living in a big universe doesn’t bother me. Even though I am a Christian. 😉
Or, rather, maybe it’s time for me to share what C. S. Lewis wrote in the mid-1940s.
I suspect the conversation between Lewis and his friend is a fictional summary of many similar discussions. But I think the points are as valid now as they were three-quarters of a century back. I’m picking up the text with remarks by the friend.
“…’You see, the real objection goes far deeper. The whole picture of the universe which science has given us makes it such rot to believe that the power at the back of it all could be interested in us tiny little creatures crawling about on an unimportant planet! It was all so obviously invented by people who believed in a flat earth with the stars only a mile or two away.’
“‘When did people believe that?’
“‘Why, all those old Christian chaps you’re always telling about did. I mean Boethius and Augustine and Thomas Aquinas and Dante.’
“‘Sorry,’ said I, ‘but this is one of the few subjects I do know something about.’
“I reached out my hand to a bookshelf. ‘You see this book,’ I said, ‘Ptolemy’s Almagest. You know what it is?’
“‘Yes,’ said he. ‘It’s the standard astronomical handbook used all through the Middle Ages.’
“‘Well, just read that,’ I said, pointing to Book I, chapter 5.
“‘The earth,’ read out my friend, hesitating a bit as he translated the Latin, ‘the earth, in relation to the distance of the fixed stars, has no appreciable size and must be treated as a mathematical point!’
“There was a moment’s silence.
“‘Did they really know that then?’ said my friend. ‘But — but none of the histories of science — none of the modern encyclopedias — ever mention the fact.’
“‘Exactly,’ said I. ‘I’ll leave you to think out the reason. It almost looks as if someone was anxious to hush it up, doesn’t it? I wonder why.’…”
(“Religion and Science”, C. S. Lewis, The Coventry Evening Telegraph, p. 4 (January 3, 1945) via “God in the Dock”, C. S. Lewis, edited by Walter Hooper (1970))
I’m quite sure that some Christians in Ptolemy’s day weren’t up to speed on the latest thing in natural philosophy.
But I figure that at least some knew about his work, they’d all have been glad to know that Christianity would be decriminalized in a few centuries, and that’s still another topic.
“…Its Inhabitants Like Grasshoppers….”
Then there’s what we knew about God, long before Ptolemy’s day.
“Indeed, before you the whole universe is like a grain from a balance,
or a drop of morning dew come down upon the earth.
“But you have mercy on all, because you can do all things;
and you overlook sins for the sake of repentance.”
(Wisdom 11:22–23)“The one who is enthroned above the vault of the earth,
its inhabitants like grasshoppers,
Who stretches out the heavens like a veil
and spreads them out like a tent to dwell in,”
(Isaiah 40:22)
And that’s all for this week, apart from the seemingly-inevitable links:
- “Back to Betelgeuse, Methenium in Orion, TRAPPIST-1 Update“
(July 1, 2023) - “WASP-18 b and Other Wonderfully Weird WASP Worlds“
(June 10, 2023) - “TRAPPIST-1 b Measured by Webb: Hot, Airless“
(April 1, 2023) - “Stars, Galaxies, XBONGs and Me“
(January 21, 2023) - “A Star by Any Other Name, and a Galilean Interlude“
(November 13, 2021)
1 Names, a nebula, JuMBOs, and a little history:
- Wikipedia
- Wiktionary
- “Jupiter Mass Binary Objects in the Trapezium Cluster“
Samuel G. Pearson, Mark J. McCaughrean; European Space Research and Technology Centre (ESTEC), European Space Agency (ESA) (October 2, 2023) via arXiv - How I see faith, science, and fallout from Victorian-era politics
- “Values and Ichthyosaurs” (September 22, 2017)
2 Discovering a mystery in the Orion Nebula:
- Wikipedia
- “Jupiter Mass Binary Objects in the Trapezium Cluster“
Samuel G. Pearson, Mark J. McCaughrean; European Space Research and Technology Centre (ESTEC), European Space Agency (ESA) (October 2, 2023) via arXiv - Mark McCaughrean (markmccaughrean.net)
3 Stars and planets, names and defitions:
- Wikipedia
- 55 Cancri
- Brown dwarf
- Ceres (dwarf planet)
- Definition of planet
- Dwarf planet
- Exoplanet
- Gas giant
- Geophysical definition of planet (defined by International Union of Geological Sciences (IUGS))
- IAU definition of planet (defined by International Astronomical Union (IAU))
- Lists of exoplanets
- Pluto
- River
- Royal Astronomical Society
- Royal Astronomical Society of Canada
- Royal Astronomical Society of New Zealand
- Solar System (eight confirmed planets: Ceres and Pluto redefined as a dwarf planets in 2006 by IAU)
- Substellar object
- Counting worlds in our planetary system
- “TRAPPIST-1 b Measured by Webb: Hot, Airless” (April 1, 2023)
4 Doubles, data, definitions and hypotheses:
- Wikipedia
- “Jupiter Mass Binary Objects in the Trapezium Cluster“
Samuel G. Pearson, Mark J. McCaughrean; European Space Research and Technology Centre (ESTEC), European Space Agency (ESA) (October 2, 2023) via arXiv - “James Webb telescope makes ‘JuMBO’ discovery of planet-like objects in Orion“
Jonathan Amos, BBC News (October 2, 2023) - “Webb’s wide-angle view of the Orion Nebula is released in ESASky“
Webb, Space Science, Science and Exploration, ESA (October 2, 2023)
5 Science, potholes and the news:
- Wikipedia
- “Fact check: No, a black hole didn’t end reality in 2012“
Nate Trela, USA TODAY (November 30, 2022)
- Wikipedia
- “Scientists get closer to solving mystery of antimatter“
Pallab Ghosh, BBC News (September 27, 2023)
- Wikipedia
- CERN
- “ALPHA experiment at CERN observes the influence of gravity on antimatter“
Physics, News (September 27, 2023) - “ALPHA cools antimatter using laser light for the first time“
Press Release (March 31, 2021) - Antimatter
- “ALPHA experiment at CERN observes the influence of gravity on antimatter“
- “Scientists get closer to solving mystery of antimatter“
Pallab Ghosh, BBC News (September 27, 2023)
8 Cosmic monsters and cosmology:
- Wikipedia
- Gamma Rays
NASA Science
- Wikipedia
