Puzzling asteroid observations explained by destruction of asteroids close to sun

February 17, 2016
The actual mechanism causing asteroids to disrupt is still unknown but some obvious scenarios such as tidal forces caused by the Sun and direct sublimation of silicates have been ruled out. One of the remaining scenarios is that volatiles inside the asteroid sublimate at moderate temperatures and create enough pressure to blow up the body. A similar process on a smaller scale called spalling can also break up surface rocks. Credit: Lauri Voutilainen

For two decades it was thought that most near-Earth objects (NEOs)—asteroids and comets that may pose a hazard to life on Earth—end their existence in a dramatic final plunge into the Sun. A new study published on Thursday, Feb. 18, in the journal Nature finds instead that most of those objects are destroyed much farther from the Sun than previously thought. This surprising new discovery explains several puzzling observations that have been reported in recent years.

An international team composed of researchers from Finland, France, the United States and the Czech Republic originally set out to construct a state-of-the-art model of the NEO population that is needed for planning future asteroid surveys and spacecraft missions. The model describes the NEOs' orbit distribution and estimates the number of NEOs of different sizes.

The vast majority of NEOs originate in the doughnut-shaped between the orbits of Mars and Jupiter. The orbit of a main-belt asteroid slowly changes as it is pushed by the uneven release of excess solar heat from the asteroid's surface. The asteroid's orbit eventually interacts with the orbital motions of Jupiter and Saturn changing the trajectory to bring the asteroid close to the Earth. An asteroid is classified as an NEO when its smallest distance from the Sun during an orbit is less than 1.3 times the average Earth-Sun distance.

The team used the properties of almost 9,000 NEOs detected in about 100,000 images acquired over about 8 years by the Catalina Sky Survey (CSS) near Tucson, Arizona, to construct the new population model. One of the most challenging problems facing the team was computing which asteroids they could actually detect. An asteroid appears as a moving point of light against a background of fixed stars but detecting it on an image depends on two factors - how bright it is and how fast it seems to be moving. If the telescope isn't looking in the right location at the right time when an asteroid is bright enough and slow enough to be detected, we simply may never find that asteroid. Accounting for these observational selection effects required a detailed understanding of the operations of the telescope and detector systems and a tremendous amount of computing time even with novel, fast mathematical techniques. The team produced the best-ever model of the NEO population by combining information about CSS's selection effects with the CSS data and theoretical models of the orbit distributions of NEOs that originate in different parts of the main asteroid belt.

But they noticed that their model had a problem - it predicted that there should be almost 10 times more objects on orbits that approach the Sun to within 10 solar diameters. The team then spent a year verifying their calculations before they came to the conclusion that the problem was not in their analysis but in their assumptions of how the Solar System works.

Dr. Mikael Granvik, a research scientist at the University of Helsinki and lead author of the Nature article, hypothesized that their model would better match the observations if NEOs are destroyed close to the Sun but long before an actual collision. The team tested this idea and found an excellent agreement between the model and the observed population of NEOs when they eliminated asteroids that spend too much time within about 10 solar diameters of the Sun. "The discovery that asteroids must be breaking up when they approach too close to the Sun was surprising and that's why we spent so much time verifying our calculations," commented Dr. Robert Jedicke, a team member at the University of Hawai'i Institute for Astronomy.

The team's discovery helps to explain several other discrepancies between observations and predictions of the distribution of small objects in our Solar System. Meteors, commonly known as shooting stars, are tiny bits of dust and rock that are dislodged from the surfaces of asteroids and comets that then end their lives burning up as they enter our atmosphere. Meteors often travel in "streams" that follow the path of their parent object, but astronomers have been unable to match most of the meteor streams on orbits closely approaching the Sun with known parent objects. This study suggests that the parent objects were completely destroyed when they came too close to the Sun - leaving behind streams of meteors but no parent NEOs. They also found that darker asteroids are destroyed farther from the Sun than brighter ones, explaining an earlier discovery that NEOs that approach closer to the Sun are brighter than those that keep their distance from the Sun. The fact that dark objects are more easily destroyed implies that dark and bright asteroids have a different internal composition and structure.

According to Granvik, their discovery of the catastrophic loss of asteroids before a collision with the Sun allows planetary scientists to understand a variety of recent observations from a new perspective but also leads to a more profound advance in asteroid science:

"Perhaps the most intriguing outcome of this study is that it is now possible to test models of interiors simply by keeping track of their orbits and sizes. This is truly remarkable and was completely unexpected when we first started constructing the new NEO model."

Explore further: Dead comets and near-earth encounters

More information: Mikael Granvik, Alessandro Morbidelli, Robert Jedicke, Bryce Bolin, William F. Bottke, Edward Beshore, David Vokrouhlický, Marco Delbò, and Patrick Michel (2016). Super-catastrophic disruption of asteroids at small perihelion distances. Nature 530. DOI: 10.1038/nature16934

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22 comments

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Maggnus
3.7 / 5 (9) Feb 17, 2016
Amazingly, no mention of lightning destroying these asteroids! Maybe it's due to their being too close to Saturn.

Steelwolf
1 / 5 (6) Feb 17, 2016
Considering that they have been diving into a heavier and heavier charged plasma solar wind I would think that at some point there would be a wide scale high voltage, low resistance acing across large sections of the object which, due to the static electricity build up from it's friction with this very solar wind. At some point it is going to gain the internal heat to boil any sort of volatile left in the object, water, methane or complex carbonates and yes, it is going to nearly vaporize anything that gets close to the sun. You can almost consider the Sun to be one big Bug Zapper in this context.

Amazing how some studiers of specific sciences never look out of their own bubble at what others are doing and be able to apply what is leaned from that to their own work, when others can clearly see the correlations between the data sets and methods. So much can be leaned when the blinders are removed.
Solon
1 / 5 (4) Feb 17, 2016
So that's what the Sun looks like from space, always wondered about that.
Captain Stumpy
5 / 5 (4) Feb 18, 2016
Amazing how some studiers of specific sciences never look out of their own bubble at what others are doing
@steel
so... you've never heard of PPPL.gov then? did you know that there are a few other labs just like PPPL?
did you read the authors and their affiliations?

http://www.nature...fil-auth

Gigel
5 / 5 (4) Feb 18, 2016
Steel: What voltage and charge are you having in mind exactly? How large are they?
Maggnus
3.9 / 5 (7) Feb 18, 2016
Amazing how some studiers of specific sciences never look out of their own bubble at what others are doing and be able to apply what is leaned from that to their own work, when others can clearly see the correlations between the data sets and methods. So much can be leaned when the blinders are removed.
What is even MORE amazing is to watch the acolytes of debunked and discredited delusions arising from the drug-addled minds of people who see star beings in cave man drawings, twist themselves into pretzels in some lame attempt to save an untenable ghost of an idea.

It is a good thing to have an open mind. That does not mean one's mind must be so open that one's brains leak out.
yep
2.3 / 5 (6) Feb 19, 2016
Amazingly, no mention of lightning destroying these asteroids! Maybe it's due to their being too close to Saturn.


If your preconceived bias was not so strong you might realize this article did not take away from EU but gave it more credence.
http://www.holosc...science/
jonesdave
5 / 5 (4) Feb 19, 2016
Amazingly, no mention of lightning destroying these asteroids! Maybe it's due to their being too close to Saturn.


If your preconceived bias was not so strong you might realize this article did not take away from EU but gave it more credence.
http://www.holosc...science/


Yeah, right. Come back to us when you've found this variable charge that these asteroids are supposed to be travelling through. And when you've found the current to power the Sun. And when we find any evidence whatsoever for the supposed electric comets. Evidence is king. You have none. Just some silly ideas.
Maggnus
3.9 / 5 (7) Feb 19, 2016
Amazingly, no mention of lightning destroying these asteroids! Maybe it's due to their being too close to Saturn.


If your preconceived bias was not so strong you might realize this article did not take away from EU but gave it more credence.
http://www.holosc...science/

AH ANOTHER ACOLYTE!

Tell me believer, other than word salad, what does that opinion piece you linked actually provide in the way of science? In typical EU fashion, they have strung together a bunch of sciency-sounding gibberish surrounded by disclaimers, contradictions and speculation.

If my aunt had balls, she would be my uncle. That should be in the header of every article written by the EU sect. Fiction is great fun.
yep
1.7 / 5 (6) Feb 21, 2016
http://www.space....ons.html
This is not the1950's we know there is charge seperation in space.
Acolyte! That's rich coming from etablishment dupes belivieng in Big Bang, Black Holes, Dark Matter, and other physics defying nonsense. Talk about gibberish contradictions and speculation.
Maggnus
4.3 / 5 (6) Feb 21, 2016
http://www.space.com/23747-earth-radiation-belts-fast-electrons.html
This is not the1950's we know there is charge seperation in space.
Acolyte! That's rich coming from etablishment dupes belivieng in Big Bang, Black Holes, Dark Matter, and other physics defying nonsense. Talk about gibberish contradictions and speculation.


Another Acolyte who posts articles only because they contain the words :"electric" or "magnetic' in the title. Do you know what confirmation bias is? A half-witted attempt to fit the square peg of actual science into the round empty hole that is EU.

Electrical fields have been known for generations. The empty pseudo-scientific rhetoric you parrot is the stuff of belief, not reality.
yep
1 / 5 (5) Feb 22, 2016
http://phys.org/n...eld.html
Layers of charge! The problem lies in your inability to see the larger picture. Western minds have such love for the box. Your inability to comprehend is tipical of the science orthodoxy that is more like a religious dogma than the questioning pursuit it ought to be. Yes generations of so full of rightiousness that they suppress ideas until time and technology shows them for the fools they are. You rail about pseudo science yet belive in miracles because authority has told you it was truth. Who is the parrot? When I was younger I believed much like you. Not any more. Good luck with all your ultra dense, multi universe, black magic.
Maggnus
4.3 / 5 (6) Feb 22, 2016
Another example of linking an article because it says "Electrical" in the title!!

Layers of charge! The problem lies in your inability to see the larger picture. Western minds have such love for the box. Your inability to comprehend is tipical of the science orthodoxy that is more like a religious dogma than the questioning pursuit it ought to be. Yes generations of so full of rightiousness that they suppress ideas until time and technology shows them for the fools they are. You rail about pseudo science yet belive in miracles because authority has told you it was truth. Who is the parrot? When I was younger I believed much like you. Not any more. Good luck with all your ultra dense, multi universe, black magic.
Empty headed rhetoric!
yep
1 / 5 (4) Feb 23, 2016
http://onlinelibr...904/full
This one says magnetic field and currents but will you connect the dots and consider the circuit like connection between the sun and all the planets? Probably not because your faith lies in the gravity based belief system resting upon the miracles of your forefathers who decided what reality was before we knew what questions to ask. It still seems mind boggling that you belive the astrophysical priests because of their authority and do not question the ridiculous assumptions of that orthodoxy. What a gravy train of theoretical speculation. maybe those miniature black holes are sucking common sense out of your brain. Must come from those other dimensions that dark matter hides in. LOL
Your wasting time with me, I've read enough science history to prevent me from believing authority based on assumptions.
Steelwolf
1 / 5 (3) Feb 24, 2016
Gigel, you can get the voltage as a product of the cross section of the size of the asteroid, it's speed and the projected density of the solar wind at any point (ISWA maps do great for showing solar wind in real time with magnetic flux lines along the planetary tracks) that being a variable. The albedo would have to do with the darker objects soaking up and thus retaining the heat longer than a shiny one would (the basis of the article you posted, very simple idea there) but the amount of arcing, even at a very low level, is going to lead to retained heat at a higher rate, low albedo or high, and work to disintegrate the asteroid at a further distance than expected because of the object not being able to dump the heat quick enough due to the constant slow buildup of heat from the arching across areas of different potential (basic electronics even) and even aircraft have to be discharged when they land, before refueling due to static electricity.
Steelwolf
1 / 5 (3) Feb 25, 2016
Also, anything in space is subject to ionizing radiation and that creates a charge in and of itself. It needs to only be a few hundred volts, at an amp or three, covering a football field sized area to create extra heat in a low albedo asteroid anyhow. Nearly all asteroid types have at least 20% iron to them meaning that they will respond to magnetic induction heating as well as have the possibility of being conductive to some degree. The story pointed out that there was problems with their prior modeling, with the asteroids breaking up sooner than expected, I am just showing some basic, real world methods of this happening. Any welder can tell you about retained heat from arcing, as can electricians.

And yes, Stump, I noticed the affiliations of the groups involved, and it is pretty slim on the cross disciplines in the sciences: Astronomers, couple of geologists and computer coders and modeling specialists. Not much in the way of people that know how things work having DONE things
Captain Stumpy
3.7 / 5 (3) Feb 25, 2016
Your wasting time with me, I've read enough science history to prevent me from believing authority based on assumptions
and therein lies the whole problem
you read science history

NOT "you read physics and understand how the eu can't be physically real because in too many cases it violates the laws of physics"

you said "I've read enough science history"

apparently you DIDN'T understand the one most important thing demonstrated throughout ALL of the science history ... the EVIDENCE always wins out over BELIEF

when you get done verifying that fact, try this on for size:
http://ocw.mit.ed...ophysics

it is NOT based upon a subjective opinion of what happened
it is ALL evidence based and built upon that fact
Captain Stumpy
3.7 / 5 (3) Feb 25, 2016
I noticed the affiliations of the groups involved
@steel
uhm... i don't think you get my point, especially as you then continued with
Not much in the way of people that know how things work having DONE things
so... you are making an ASSumption of what, then?

spell it out... or is it going to be the same old completely debunked eu argument WRT astrophysicists?
i mean... that whole argument can be completely ignored simply because there are NO astro curriculum that i've ever seen from ANY college that has ignored or not had: plasma physics, or studies on electromagnetism, or particle physics, or... (you should get that point)

so by all means, spell it out and be more clear so it can be addressed!
and show the evidence where the above authors are incapable of "knowing how things work" because of their [insert reason here]

that should be easy enough for you given you spotted it right off, right?
AGreatWhopper
2.3 / 5 (3) Feb 25, 2016
I wish all the electricity cranks would sit down and shut up. https://images.du...&f=1
chileastro
3 / 5 (2) Feb 26, 2016
They're not here by accident. Did you see the advert in the middle of the page for the Tesla coil that will "rid you of your electric bill"? It's a total scam. http://www.sandie...gy-scam/

They're taking money from the cranks-turned-crooks, so why would they do anything about the lot of Tesla loonies?
Steelwolf
not rated yet Feb 26, 2016
Actually Stump, I was pointing out that too many of the physicists and astronomers and modeling specialists all too often have not had enough of the Real World experience in other areas where similar skills are used, the different disciplines that have a lot of crossover potential they have not been exposed to. This is one of the great problems of insularity in the fields of Astronomy and Physics in General. Many are college students or professors who still tend to be stuck in an insular Ivory Tower situation, speaking the great arcane language of 'Higher Math' making them part of a small club
Note: I say there is the Tendency towards this, as it tends to be 'The Rule' if you are to get funding, however there Are the outliers who DO produce relevant, solid data by the the standards of modern science: peer reviewed and published data in different fields that would help to understand what is going on at Macro-Cosmic Scale by studying the Micro-Quantum regime. Fractal Iterations all!
Steelwolf
not rated yet Feb 26, 2016
And YES, I Do happen to understand that in this day of the internet that there is a much greater collaboration amongst scientists, however it tends to be people from different geographic areas that are still studying the very same science, say Astronomy, geophysics and astro-physics, working together on projects of their own sub-specialty. What I am pointing out is that there are not enough people who are working to Specifically collect and connect the dots between enough studies, across enough different disciplines to be Constructivists: Ones who can see how things that do not Seem to correspond to each other actually form patterns that can be seen as fractal iterations of all kinds of subjects, from social type studies to chemical and physics on the gross, micro and quantum scales compared to larger structures such as globular clusters, galaxies, back holes, galactic clusters and Filaments and how well they compare to effects seen at Quantum scale after a rescaling of time.

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