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Why Earth is so much bigger than Mars: Rocky planets formed from 'pebbles'
Science Daily ^ | 10/27/2015 | Southwest Research Institute

Posted on 10/27/2015 11:47:58 AM PDT by JimSEA

Using a new process in planetary formation modeling, where planets grow from tiny bodies called "pebbles," Southwest Research Institute scientists can explain why Mars is so much smaller than Earth. This same process also explains the rapid formation of the gas giants Jupiter and Saturn, as reported earlier this year.

"This numerical simulation actually reproduces the structure of the inner solar system, with Earth, Venus, and a smaller Mars," said Hal Levison, an Institute scientist at the SwRI Planetary Science Directorate. He is the first author of a new paper published in the Proceedings of the National Academy of Sciences (PNAS) Early Edition.

[snip]

However, these new models find that not all of the primordial asteroids are equally well-positioned to accrete pebbles and grow. For example, an object the size of Ceres (about 600 miles across), which is the largest asteroid in the asteroid belt, would have grown very quickly near the current location of the Earth. But it would not have been able to grow effectively near the current location of Mars, or beyond, because aerodynamic drag is too weak for pebble capture to occur.

(Excerpt) Read more at sciencedaily.com ...


TOPICS: Astronomy; Science
KEYWORDS: asteroids; astronomy; catastrophism; deusexmachina; earth; jupiter; mars; mercury; neptune; pluto; saturn; science; solarsystem; uranus; venus; xplanets
This will be interesting to follow as there should be validating observations both in our system and in the stars we are now finding the are both in the process of forming planets and those already formed.
1 posted on 10/27/2015 11:47:58 AM PDT by JimSEA
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To: JimSEA

“near the current location of Mars, or beyond, because aerodynamic drag “

Aerodynamic drag in outer space?
I don’t believe it. What next?
Mud flaps and spoilers on the Enterprise?


2 posted on 10/27/2015 12:35:19 PM PDT by sparklite2 (All will become clear when it is too late to matter.)
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To: sparklite2

There was a ring of dust from which all the planets, etc. formed not your “empty” space


3 posted on 10/27/2015 12:45:32 PM PDT by JimSEA
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To: JimSEA

For the drag to be aerodynamic does it not require air?


4 posted on 10/27/2015 12:53:03 PM PDT by sparklite2 (All will become clear when it is too late to matter.)
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To: sparklite2

Never mind. It can be gas. And where there’s gas, there’s drag.


5 posted on 10/27/2015 12:55:43 PM PDT by sparklite2 (All will become clear when it is too late to matter.)
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To: sparklite2

Yes, you are correct. Remember the gas giants also formed from this ring of dust, etc.


6 posted on 10/27/2015 1:05:17 PM PDT by JimSEA
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To: sparklite2
"Betelgeuse has evolved rapidly because of its high mass. Having been ejected from its birthplace in the Orion OB1 Association—which includes the stars in Orion's Belt—this crimson runaway has been observed moving through the interstellar medium at a supersonic speed of 30 km/s, creating a bow shock over 4 light-years wide."
7 posted on 10/27/2015 1:14:18 PM PDT by jpsb (Believe nothing until it has been officially denied)
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To: sparklite2
"Betelgeuse has evolved rapidly because of its high mass. Having been ejected from its birthplace in the Orion OB1 Association—which includes the stars in Orion's Belt—this crimson runaway has been observed moving through the interstellar medium at a supersonic speed of 30 km/s, creating a bow shock over 4 light-years wide."
8 posted on 10/27/2015 1:14:33 PM PDT by jpsb (Believe nothing until it has been officially denied)
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To: KevinDavis; annie laurie; Knitting A Conundrum; Viking2002; Ernest_at_the_Beach; Mmogamer; ...

Thanks JimSEA.
 
X-Planets
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9 posted on 10/28/2015 3:06:20 PM PDT by SunkenCiv (Here's to the day the forensics people scrape what's left of Putin off the ceiling of his limo.)
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To: 75thOVI; Abathar; agrace; aimhigh; Alice in Wonderland; AndrewC; aragorn; aristotleman; ...

Thanks JimSEA.


10 posted on 10/28/2015 3:06:41 PM PDT by SunkenCiv (Here's to the day the forensics people scrape what's left of Putin off the ceiling of his limo.)
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