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Darker Stars

My latest book, entitled “Darker Stars” is now available in paperback. The book’s sub-title is “New Evidence: The Scope of Our Growing Solar System, Planet X, Invisible Planetoids, Gas Giants, Comets, Planet Nine, and More…”. Here is the description on the back cover:

“Darker Stars explores the often contentious subject of Planet X. Building upon the historically hot-and-cold hunt for an additional planet in our solar system, the author examines the recent resurgence of scientific interest in this subject, in the re-branded form of Planet Nine. The elusive nature of this object provides the impetus for a hypothesis about planet building in interstellar space, and associated phenomena. In particular, free-floating planetary mass objects and sub-brown dwarfs exemplify the anomalous new characters shaking the foundation of the classic star/planet boundary.

“Our solar system, too, is full of anomalies, strongly implying the presence of another massive planetary body. As our understanding of dark bodies in interstellar space builds, the author argues whether the existence of Planet X-type bodies should now be considered the new norm. With over 100 images and sources, approximately 500 references, and an extensive index, Darker Stars provides a robust and scientifically-based study of the re-fashioned outer solar system.”

The book is 376 pages long, and is published by Timeless Voyager Press in a 6″x9″ paperback format, available through Amazon.  There is a vast amount of information about the mysteries of the outer solar system within the book.  The book also discusses recent advances in understanding about the outer solar system, and hypotheses about Planet X and its re-branded corollary Planet Nine. I present a new hypothesis about how planets might evolve over time in interstellar space, and how this process may explain why Planet X has been so difficult to observe directly. Why assume objects beyond Neptune form the same way as those within? Drag and solar wind effects on dust will be different, even more so in interstellar space beyond heliosphere. New rules are needed for the outer solar system. #darkerstars

Planetary Nebula

‘Darker Stars’ brings together a decade of Dark Star blogs and articles, updated with brand new material, and then completely re-written into a comprehensive and fully-referenced non-fiction book. It is both robust and challenging in its approach.

Book Contents

Chapter 1        The Incomplete Solar System

Chapter 2        The History of Planet X

Chapter 3        Sub-Brown Dwarfs in the Infrared

Chapter 4        The Extended Scattered Disk

Chapter 5        Re-Branding Planets

Chapter 6        The Hunt for Planet Nine

Chapter 7        Arguments Against Planet Nine

Chapter 8        Planet Nine and the Nice Model

Chapter 9        Further Planet X Evidence Among The Minor Bodies

Chapter 10      The Origins of Planet X

Chapter 11      Building Planets in Interstellar Space

Chapter 12      The Shroud Hypothesis

Chapter 13      An Abundance of Dark Stars

Chapter 14      ‘Oumuamua

Chapter 15      Jovian Mysteries

Chapter 16      Puzzling Pluto

Chapter 17      Meandering Mars

Chapter 18      Water World

Chapter 19      Moon Mysteries

Chapter 20      Comets and Asteroids

Chapter 21      Nibiru

Chapter 22      The Dark Star Revisited

Online Retailers

Darker Stars cover

The new paperback book is available from Barnes and Noble:

 https://www.barnesandnoble.com/w/darker-stars-andy-lloyd/1130303630?ean=9781892264558 

It is also available from many other reputable booksellers online. including Amazon:.

   

Signed Copies

Signed and dedicated copies of the book can be obtained directly from me: I’m based in England, so bear in mind the likely postal costs for what is quite a substantial book!

Author Andy Lloyd presents his new book ‘Darker Stars’

Please e-mail Andy Lloyd for further details at andy-lloyd@hotmail.com

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Planet Nine – 3 Years on

There is no doubt that the scientific advocacy for a Planet X body has been significantly strengthened by the work of Brown and  Batygin, who published their first paper about ‘Planet Nine’ three years ago (1).  Mike Brown is a renowned astronomer in academic circles, whose speciality is hunting down distant Kuiper Belt Objects and dwarf planets in the outer solar system. 

Following on from the work of Trujillo and Sheppard (2), he and his Caltech colleague Konstantin Batygin studied odd similarities in the orbits of distant scattered disk objects (SDOs) which lie beyond the regular Kuiper belt.  Certain orbital properties of these eschewed objects seemed to be gathered into place within a common clustering, and the astrophysicists determined that something massive located well beyond them must have been responsible for shepherding these objects into such a serendipitous arrangement.  They advocated a renewed search for Planet X, which had been confined to the doldrums of astronomy for decades, and re-branded the object ‘Planet Nine’ (3).

Relative Positions of the KBO Cluster Pointing to Planet Nine. Image credit: Caltech

Planet Nine is thought to be a super-Earth object, upwards of 10 Earth masses.  Searches for exoplanets have determined that such planets are common enough elsewhere, but, so far as we know, absent from our own shores within this solar system.  Planet Nine is likely twenty times further away from us than Pluto, maybe more, and how such an object could have ended up so far away from the rest of the planets has vexed scientists.  Of course, it remains hypothetical, because, despite the observational strength of modern day astronomy, Planet Nine has not been located.  Its position is unknown (beyond ruling out certain sections of the sky), as its existence can only be inferred from the clustering data, but not determined directly from it.

Despite its 3-year long ‘no-show’, Brown and Batygin stand by their initial paper, and have published a follow-up paper this month to continue to argue their case (4).  It primarily responds to the arguments raised by scientists working for the Outer Solar System Origins Survey (OSSOS) who found similar objects which did not seem to belong to the P9 cluster (5), and who went on to argue that the evidence for Planet Nine should be dismissed due to inherent observational bias in the data (6).  At the time, Batygin quickly refuted that criticism, finding more patterns in the outer solar system snow, although I wondered whether the OSSOS data may be opening up another issue entirely about Planet Nine’s argued-for position (7).  Anyway, Brown and Batygin’s new paper presents their subsequent work about the issue of observational bias, and offers a robust analysis leading to following conclusion:

“From this now more complete understanding of the biases, we calculate that the probability that these distant KBOs would be clustered as strongly as observed in both longitude of perihelion and in orbital pole position is only 0.2%. While explanations other than Planet Nine may someday be found, the statistical significance of this clustering is now difficult to discount.” (4)

Having rebutted their critics on one front, the Caltech team face another problem this month, this time in the form of an alternative explanation for the clustering anomalies proposed by researchers from the University of Cambridge.  This new hypothesis involves the possible existence of a very significant disk of objects beyond the Kuiper belt, with a combined mass of 10 Earth masses, or perhaps less. 

This massive ring of material would be eccentrically inclined to the invariant plane of the planets.  The astrophysicists’ calculations and simulations show that such a massive eccentric disk might have the gravitational pull to create the observed clustering of extreme SDOs (8), but the mass required represents a couple of orders of magnitude of mass greater than the known Kuiper belt.  Arguing that studies of other young star systems show extended debris disks, the authors seem quietly confident about the potential existence of such a massive extended disk:

Credit: ESO/M. Kornmesser

““If you remove planet nine from the model and instead allow for lots of small objects scattered across a wide area, collective attractions between those objects could just as easily account for the eccentric orbits we see in some TNOs,” said [Antranik] Sefilian, who is a Gates Cambridge Scholar and a member of Darwin College.” (9)

Brown points out that it’s unusual in science for a new hypothesis – in this case the proposed existence of Planet Nine to explain the observed clustering of SDOs – to not face a barrage of counter-hypotheses.  For some reason, all of the attention up until this point has been focussed upon the statistical credibility of the cluster properties.  Brown acknowledges the new Cambridge paper is the first stab at an alternative explanation for the extended SDO cluster (11).  In fact, a similar explanation has already been offered within academic circles, by a group based in Colorado led by Ann Marie Madigan last summer.  The Colorado group argued that a significant amassed collection of distant asteroids could explain the observed anomalies (10).  Mike Brown explains the difference between these two papers: “…although the hypotheses sound similar, they are really totally unrelated. The one from last summer doesn’t actually explain…what we see. This one, at least, does.” (12)

Despite actually offering what appears to be a mathematically credible explanation, Brown is sceptical of the new Cambridge paper on a couple of fronts: (1) The required mass of the disk (as above), and (2) its provenance (11).  How could such a warped extended disk have been shaped in the first place?  This raises another vexed question about how such a weird disk came to be, which flies in the face of the Cambridge authors’ claim to have provided a simpler explanation than Planet Nine.

It is known that the invariant plane of the planets is warped away from the solar equatorial plane by about 6-7 degrees.  Planet Nine, on the other hand, is likely to be inclined by about 30 degrees, and may itself represent an explanation for this warping, should its mass be significant enough to have shaped the rest of the solar system in this way.  One of the several strands of evidence pointing towards the existence of a Planet Nine/X body is the ~6 degree tilt of the invariant plane of the planets away from the Sun’s own equatorial plane.  In other words, like the Earth, the Sun’s axis is tilted away from the plane of the planets.

All things being equal, the Sun and the planets should have formed out of a common rotating disk of primordial matter – the coalescing pre-solar nebula.  It’s understandable that many of the planets engaged in a bit of to-and-fro during the early period of planet-forming, and so ended up a little skewed.  But the Sun is the dominant player, and it should take a considerable gravitational influence to draw the planets away from its own equatorial plane.  Yet, the Sun is seemingly a lonely star.  So, that pesky 6 degree tilt has to be explained by something.  Maybe a passing star pulling at the planets at some point in the past; or maybe the Sun had an early companion (within its birthing dense core) which affected the system’s alignment; or maybe another significant planet strongly inclined to the ecliptic, influencing the others over time (13).

Studies of protoplanetary disks in young star systems is revealing similar warps elsewhere.  The latest case concerns a very young single protostar system known as L1527.  This system is so young that there is an implication that the warping may be occurring in the primordial cloud itself (14).  The disk in question is effectively in two parts, where the warping issue affects the inner disc out to some 40-60 AU from the star (15).  In the perceived absence of a companion object causing this effect, it is thought that the gravitational effect of the cloud itself is causing the warp in the protoplanetary disk.

But here’s the thing:  Just because there isn’t a self-evident, luminous companion object near to L1527, doesn’t mean that there isn’t a darker companion lurking around somewhere nearby, tugging at the disk.  It has been suggested that all stars begin  life within dense cores, containing at least two protostars (16).  In turn, this has implications about the potential for failed stars being ubiquitous companion objects (17).  So, maybe L1527 does have an unseen sub-stellar companion affecting the structure of its inner disk.

Image Credit: (18)

Another item of interest to add is news about another misaligned disk, this time around a young binary star system (19).  In this case, the disk orbits at right angles to the orbit of the two stars which make up the binary HD 98800, meaning that the disk is in a perpendicular polar misalignment (19).  Furthermore, the authors state that despite the extreme misalignment, the disk itself has physical properties similar to those around single stars, including, therefore, potential planet forming conditions.

So it is clear that such warped arrangements are by no means confined to the solar system, can be pretty extreme, and can appear very early on in the lifetime of a star system.  What’s less clear is why they arise in the case of sible star system, seemingly minding their own business.  Some kind of distant, dark companion object pulling at the rest of the system seems a reasonable enough explanation – one that was already present, or co-forming, within the stellar birth cluster.  Perhaps that might be a body the size of Planet Nine (a proposed super-Earth), perhaps something bigger still.

So, happy third birthday, Planet Nine!  You may still be a mere twinkling in a Californian astronomer’s eye, but you’ve already evoked a modern renaissance in the history of Planet X.

Written by Andy Lloyd, 24th January 2019

References:

1)  K. Batygin & M. Brown “Evidence for a Distant Giant Planet in the Solar System” The Astronomical Journal, 20 January 2016, 151(2)

2)  Chad Trujillo & Scott Sheppard “A Sedna-like body with a perihelion of 80 astronomical units” Nature, 27 March 2014, 507: 471-474, http://www.nature.com/nature/journal/v507/n7493/full/nature13156.html

3)  Andy Lloyd “Massive Planet X Now Urgently Sought by Top Planet-Hunters” 20-23 January 2016, http://www.andylloyd.org/darkstarblog34.htm

4)  Michael Brown and Konstantin Batygin “Orbital Clustering in the Distant Solar System” The Astronomical Journal, 22 January 2019, 157(2)

5)  Cory Shankman et al. “OSSOS VI. Striking Biases in the detection of large semimajor axis Trans-Neptunian Objects”, 19th June 2017, The Astronomical Journal, 14 July 2017, 154(2)

6)  Josh Sokol “New haul of distant worlds casts doubt on Planet Nine”, 21st June 2017 http://www.sciencemag.org/news/2017/06/new-haul-distant-worlds-casts-doubt-planet-nine

7)  Andy Lloyd “Planet Nine: Are They Digging in the Wrong Place?” 3 July 2017 http://andy-lloyd.com/planet-nine-digging-wrong-place/

8)  Antranik Sefilian and Jihad Touma. ‘Shepherding in a self-gravitating disk of trans-Neptunian objects.’ The Astronomical Journal 21 January 2019, 157(2) https://iopscience.iop.org/article/10.3847/1538-3881/aaf0fc/pdf

9)  Sarah Collins “Mystery orbits in outermost reaches of solar system not caused by ‘Planet Nine’, say researchers” 21 January 2019 https://www.cam.ac.uk/research/news/mystery-orbits-in-outermost-reaches-of-solar-system-not-caused-by-planet-nine-say-researchers

10) Daniel Strain “Collective gravity, not Planet Nine, may explain the orbits of ‘detached objects'” 4 June 2018 https://www.colorado.edu/today/2018/06/04/collective-gravity

11)  Mike Brown “Is Planet Nine just a ring of icy bodies?” 22 January 2019 http://www.findplanetnine.com/

12)  @plutokiller replying to @darkstarandy, 24/1/19

13)  Andy Lloyd “Does Planet Nine Solve the Riddle of the Sun’s Obliquity?” 30th July 2016 http://andy-lloyd.com/planet-nine-solve-riddle-suns-obliquity/

14)  RIKEN Press Release “Early protostar already has a warped disk” 1 January 2019, http://www.riken.jp/en/pr/press/2019/20190101_1/

15)  Nami Sakai et al. “A warped disk around an infant protostar” Nature, 31 December 2018, https://www.nature.com/articles/s41586-018-0819-2

16)  Sarah Sadavoy & Steven Stahler “Embedded Binaries and Their Dense Cores” MNRAS, 21 August 2017, 469(4): pp3881–3900

17)  Andy Lloyd “The Sun was Born with a Companion” 15 June 2017 http://www.andylloyd.org/darkstarblog51.htm

18)  Peter Thorley “Double star system flips planet-forming disk into pole position” 14 January 2019 https://warwick.ac.uk/newsandevents/pressreleases/double_star_system/

19)  Grant Kennedy et al. “A circumbinary protoplanetary disc in a polar configuration” 15 january 2019 Nature Astronomy Letters, https://www.nature.com/articles/s41550-018-0667-x.epdf with thanks to Lee

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How Dust Clumps Together in Space

One of the essential ingredients of planet-building is the clumping of dust in space.  Planets can build up through the gravitational attraction of objects in space which are already about 1000km across.  The problem is how do these proto-planetessimals get built?  The mechanism for how dust clumps together has not been well understood.  After all, when materials moving at speed through space collide, they may break apart in the force of the impact, showering down collisional cascades of ever small materials – the exact opposite of planetessimal-building.  Somehow, dust must clump together into grains, which then join forces to create space pebbles, then boulders, then mountains, etc.

For these materials to adhere together, an inherent stickiness may be needed, aided by the presence of greasy organic compounds (in the form of aliphatic carbon).  While it is recognised that this greasy component is more readily available in interstellar space than previously suspected (1), does that adhesive property extend down to space dust?  If not, what mechanism could be bringing together ever larger clumps of plain old granular dust in space?

New research work suggests that dust and gas are not happy bedfellows within a magnetic field.  So, rather like oil in water, dust particles seem to come together within gas as the mixture traverses the galactic tides.  Indeed, any force brought to bear on dust moving through gas seems to create this clumping effect:

“… it was previously assumed that dust was stable in gas, meaning the dust grains would ride along with gas without much happening, or they would settle out of the gas if the particles were big enough, as is the case with soot from a fire. “…dust and gas trying to move with one another is unstable and causes dust grains to come together,” says [Phil] Hopkins [Professor of theoretical astrophysics at Caltech]...These gas-dust instabilities are at play anywhere in the universe that a force pushes dust through gas, whether the forces are stellar winds, gravity, magnetism, or an electrical field.” The team’s simulations show material swirling together, with clumps of dust growing bigger and bigger.” (2)

Computer simulations looking at how dust moves through magnetized gas seems to show this clumping effect as a general mechanism.  The dust grains are like boulders in a fast moving and turbulent river (the gas within a moving stream of magnetized material).  As the flows wrap around these grains and pull them back and forth, the grains have a tendency to coalesce, forming ever larger clumps.  This is not just applicable to planet formation in proto-planetary disks, but may also extend to interstellar space:

“As examples, we introduce several new instabilities, which could see application across a variety of physical systems from atmospheres to protoplanetary disks, the interstellar medium, and galactic outflows.” (3)  Read More…

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The Goblin Points to Presence of Planet X

The announcement of the discovery a new object in the outer solar system may bring us a step closer to the elusive Planet X (more recently dubbed Planet Nine).  This new dwarf object, known as 2015 TG387, is a distant member of the mysterious scattered disk of objects beyond the Kuiper Belt.  This particular object can travel so far away from the Sun during its orbit that it moves through the inner Oort cloud of comets, beyond 2000AU:

The newly discovered object is called 2015 TG387, is probably a small dwarf planet at just 300km across, and is incredibly far away. It is currently lying about two and a half times further away from the Sun than Pluto is.  It often reaches much further away. Its orbit takes it to about 2,300 AU — that is 2,300 times as far away from the sun as we are, and vastly more than the already huge 34 AU that the distant Pluto sits at.(1)

The object’s vast orbit is so vast that it takes about 40,000 years to do one circuit around the Sun.  Yet, its orbit is highly eccentric.  It distance from the Sun varies from 64AU at perihelion to 2037AU at aphelion.  Incredibly, then, it skirts both the Kuiper Belt and the inner Oort cloud, transiting between these quite distinct belts of objects.

As more objects are discovered between the Kuiper Belt and the inner Oort cloud (a torus-shaped disk of comets), the classifications of these objects are becoming more complex.  A significant factor is whether these objects have perihelia within 40AU, which might briefly bring them within the influential scope of the planet Neptune.  Extreme scattered disk objects fall into this category.  Significantly, 2015 TG387 is fully detached from this influence at perihelion, and may be considered to be an inner Oort cloud object.  Read More…

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New Infra-red Search for sub-Brown Dwarfs Planned

Brown dwarfs are notoriously hard to find.  It’s not so bad when they are first born: They come into the Universe with a blast, shedding light and heat in an infantile display of vigour.  But within just a few million years, they have burned their available nuclear fuels, and settle down to consume their leaner elemental pickings.  Their visible light dims considerably with time to perhaps just a magenta shimmer.  But they still produce heat, and the older they get, the more likely that a direct detection of a brown dwarf will have to be in the infra-red spectrum.

This doesn’t make them much easier to detect, though, because to catch these faint heat signatures in the night sky, you first need to have a cold night sky.  A very cold night sky.  Worse, water vapour in the atmosphere absorbs infra-red light along multiple stretches of the spectrum.  The warmth and humidity of the Earth’s atmosphere heavily obscures infra-red searches, even in frigid climates, and so astronomers wishing to search in the infra-red either have to build IR telescopes atop desert mountains (like in Chile’s Atacama desert), or else resort to the use of space-based platforms.  The downside of the latter is that the telescopes tend to lose liquid helium supplies rather quickly, shortening their lifespan considerably compared to space-based optical telescopes.

The first major sky search using a space telescope was IRAS, back in the 1980s.  Then came Spitzer at the turn of the century, followed by Herschel, and then WISE about five years ago.  Some infra-red telescopes conduct broad searches across the sky for heat traces, others zoom in on candidate objects for closer inspection.  Each telescope exceeds the last in performance, sometimes by orders of magnitude, which means that faint objects that might have been missed by early searches stand more of a chance of being picked up in the newer searches.

The next big thing in infra-red astronomy is the James Webb Space Telescope (JSWT), due for launch in Spring 2019.  The JSWT should provide the kind of observational power provided by the Hubble Space telescope – but this time in infra-red.  The reason why astronomers want to view the universe in detail using infra-red wavelengths is that very distant objects are red-shifted to such a degree that their light tends to be found in the infra-red spectrum, generally outside Hubble’s operational parameters (1).  Essentially, the JWST will be able to see deeper into space (and, therefore, look for objects sending their light to us from further back in time when the first stars and galaxies emerged).  Read More…

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Return of the Pioneer Anomaly

One of the many pieces of evidence put forward for the existence of Planet X over the last few decades is the so-called ‘Pioneer anomaly’.  The two Pioneer spacecraft were sent on an incredible voyage across the solar system, visiting a number of planets as they went.  They not only imaged these planets, but used the gravity of the planets to accelerate onwards, deeper into the solar system.  This gravity assist is often used to allow spacecrafts to pick up speed.  As the Pioneer probes travelled across the outer planetary zone and on towards the Heliopause beyond in the 1990s, it became apparent that the craft were not moving away from the solar system quite as quickly as the theoretical trajectory projections demanded.  Something was essentially slowing them down.  Additionally, similar effects were noted for the Galileo and Ulysses probes.

Many ideas were put forward, including either gravitational or physical interaction with clouds of interplanetary dust in the Kuiper Belt, or even the added gravitational tug of an undiscovered Planet X body.  One of the lead researchers into the Pioneer anomaly at the Jet Propulsion Laboratory  was John Anderson (1), who, interestingly, also had a longstanding interest in the possible existence of a Planet X body (2).  At one point, puzzled physicists began to wonder whether this marginal but definitive anomaly might require new laws of physics (3).  In the end, it was agreed by technical experts that the anomalous deceleration was a result of radiation pressure caused by non-uniform heat loss from the probes (4,5). Flights of fancy about missing planets and new physics were promptly put to bed.

Despite this, the anomaly seems to persist in the increasingly accurate navigation and telemetry data returning from various spacecraft performing flybys past the Earth (6).  Similarly, the Juno spacecraft, now orbiting fairly closely around Jupiter, is reported to be slightly misplaced from its expected position (7).  This has been determined by looking at the Doppler shift of ranging data from the probe as it circumnavigated the poles of the great gas giant.  Quixotically, Juno did not exhibit the same anomalous behaviour during a previous flyby of Earth.  This suggests that this is not, then, the result of an internal machination of the probe itself, as described for the Pioneer probes.  Instead, there does appear to be an unexplained external effect worth exploring:

Another mystery is that while in some cases the anomaly was clear, in others it was on the threshold of detectability or simply absent – as was the case with Juno‘s flyby of Earth in October of 2013. The absence of any convincing explanation has led to a number of explanations, ranging from the influence or dark matter and tidal effects to extensions of General Relativity and the existence of new physics. However, none of these have produced a substantive explanation that could account for flyby anomalies.” (8)  Read More…

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Planet Nine and the Nice Model

It looks like it’ll be another long, lonely autumn for Dr Mike Brown on the summit of the Hawaiian dormant volcano Mauna Kea, searching for Planet Nine.  He made use of the 8m Subaru telescope last year, and it looks like he’s back again this year for a second role of the dice (unless he does all this by remote control from Pasadena?).  I can only assume, given the time of the year, that the constellation of Orion remains high on their list of haystacks to search.

A recent article neatly sums up the current state of play with the hunt for Planet Nine (1), bringing together the various anomalies which, together, seem to indicate the presence of an undetected super-Earth some twenty times further away than Pluto (or thereabouts).  Given how much, I’ve written about this materials already, it seems unnecessary to go over the same ground.  I can only hope that this time, Dr Brown and his erstwhile colleague, Dr Batygin, strike lucky.  They have their sceptical detractors, but the case they make for Planet Nine still seems pretty solid, even if the gloss has come off it a bit recently with the additional OSSOS extended scattered disk object discoveries (2).  But there’s nothing on Dr Brown’s Twitterfeed to indicate what his plans are regarding a renewed search for Planet Nine.

Even if the Planet Nine article’s discussion about a new hunt for the celestial needle in the haystack is misplaced, it does make a valid point that super-Earths, if indeed that is what this version of Planet X turns out to be, are common enough as exo-planets, and weirdly absent in  our own planetary backyard.  So a discovery of such an object way beyond Neptune would satisfy the statisticians, as well as get the bubbly flowing at Caltech.  Dr Brown did seem to think that this ‘season’ would be the one.  We await with bated breath…

Meanwhile, the theoretical work around Planet Nine continues, with a new paper written by Konstantin Batygin and Alessandro Morbidelli (3) which sets out the underlying theory to support the result of the 2016 computer simulations which support the existence of Planet Nine (4).  Dr Morbidelli is an Italian astrophysicist, working in the south of France, who is a proponent of the Nice model for solar system evolution (named after the rather wonderful French city where he works).  This model arises from a comparison between our solar system’s dynamics, and those of the many other planetary systems now known to us, many of which seem bizarre and chaotic in comparison to our own.  Thus, the Nice model seeks to blend the kinds of dynamical fluctuations which might occur during the evolution of a star’s planetary system with both the outcomes witnessed in our own solar system, and the more extreme exoplanets observed elsewhere (5).  It invokes significant changes in the positions of the major planets during the history of the solar system, for instance.  These migrations have knock on effects which then drive other disturbances in the status quo of the early solar system, leading to the variations witnessed both here and elsewhere.  For instance, Dr Morbidelli lists one of the several factors which brought about the Nice model:
Read More…

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August: The Traditional Planet X Silly Season

I’ve noticed that August usually brings with it a significant uptick in Planet X-related stories in the mainstream media.  Lots of people go on holiday, companies go quiet, governments tick along and seek only to bury bad news this month, and no one’s playing much attention anyway.  So, bored journalists stuck in their offices when everyone else is having fun scrabble around to produce stories, sometimes from nothing at all, other times re-hashing previous material.  More often than not, they simply nick each other’s ideas.  This year, the traditional August silly season has been marred by the rather unfortunate possibility of nuclear war.  This kind of serious topic has no place in August, so most people seem to be consigning it to the desperate summer news schedule.  I’m sure that if the threat of war on the Korean peninsula continues into September, then people will start to sit up and take notice, with the commensurate impact on stock markets, prospects of mass annihilation, etc.

Anyhow, within that context, it’s little surprise to see a story outlining the fears people have about Planet X, and how there may actually be an underlying reality behind the conspiracy theories (which there often is, in one form or another).  The celestial ball gets rolling by an online article in the Daily Star (1) which outlines the most recent nightmare scenario from the heavens, and then includes a family-friendly Planet X rebuttal on a YouTube video by NASA scientist David Morrison.  Some of the detailed points he makes are arguable (about ‘Nibiru’ being a ‘minor god in the Babylonian pantheon’, and about how great an effect a perihelion transit by a Planet X object might have upon the solar system’s architecture, for instance) but his general thrust is sound.  Don’t panic! 

Read More…

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The Origin of Ancient Xenon

I’ve often discussed the origin of various elements and compounds on Earth – most notably the isotopic ratio of water, and what that might tell us about the origin of terrestrial water (1).  Data about this can help provide evidence for the Earth’s early history, and often the data is inconsistent with the general theories of oceanic origin, like the ‘late veneer theory’, for instance, where the bulk of terrestrial waters were supposed to have been supplied by comets.  It turns out that the water was on this planet all along (2,3), raising questions about why the Sun’s heat had not driven this relatively volatile resource away from the primordial Earth during the early history of the solar system.

waterworld

Despite such evidence, the ‘late veneer theory’ continues to hold ground for many scientists, and tends to go unchallenged within the science media.  This is apparent within the following excerpt about a new paper on the mysterious presence of a particular isotope of the noble gas xenon found in ancient terrestrial water encased in rock:

“The scientists have been analysing tiny samples of ancient air trapped in water bubbles found in the mineral, quartz, which dates back more than three billion years. The team found that the air in the rocks is partly made up of an extremely rare form of the chemical element, xenon. It is known as U-Xe and what makes it so rare is that it isn’t usually found on Earth. The component is not present in the Earth’s mantle, nor is it found in meteorites.

“Therefore, the team believe that the U-Xe must have been added to the Earth after a primordial atmosphere had developed. Simply put, comets are the best candidates for carrying the U-Xe to the planet. Co-author, Prof Ray Burgess, from Manchester’s School of Earth and Environmental Sciences explains: “The Earth formed too close to the Sun for volatile elements, such as U-Xe, to easily condense and they would have rapidly boiled off the surface and been lost to space.

“”The reason that oceans and an atmosphere exist at all is because volatiles were still being added after the Earth formed. The puzzle is in identifying where the volatiles came from and what objects carried them to the early Earth. The difficulty is that many of the different volatile ingredients that were originally added have been thoroughly mixed together by geological processes during Earth’s long geological history.”” (4)

asteroid_impact

It turns out that xenon, in general, is mostly absent from the Earth’s atmosphere, particularly compared to other noble gases like argon.  No one knows why.  Perhaps the missing xenon is encapsulated within rocks buried deep within the Earth.  Or perhaps, conversely, it has been driven off the Earth because it is not easily captured by rocks like perovskite (5).  Xenon is missing from Mars, too, which may allude to its propensity for loss from a weak atmosphere.

Read More…

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Down a Dusty Lane

Picking up on the mystery of how a massive Planet X could form beyond the outer confines of the Sun’s magnetic environment, as per my previous posts on the accretion of dust beyond the heliopause (1,2) and an exploratory scientific paper I published earlier in the year (3).  I’m searching for evidence, or at least some educated guesswork, about whether interstellar medium beyond the heliosphere of stars might be sufficient over time to build up substantial, gaseous planets loosely bound to their parent star systems.  Such planets might, I suggest, accumulate dust clouds and rings around them, undisrupted by the action of the solar wind trapped within the inner magnetic sphere of the solar system.

bd_snowdisk

Even though this kind of accumulation could be gradually taking place over billions of years, creating a meaningful adjustment to the mass of a substantial planet over these kinds of time periods, it doesn’t seem likely that this kind of effect could take place if our current interstellar environment is anything to go by (although the unexpected presence of interstellar ‘fluff’ beyond the heliopause, described by NASA (4), and the intrusion of large grain particles into the outer solar system (5) do offer some evidence of what could be ‘out there’).

Last month, I looked at evidence of massive stars being aided in their development by the dumping of immense quantities of neighbouring nebula material onto them (6).  I wondered whether a similar mechanism might also be happening in interstellar space at the planetary level, based upon globular frameworks of nebula materials (like gigantic molecular clouds, and the like).

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