The Super Earths
01- K-11
02- Migrating Worlds
03- Gliese 581
04- Goldilocks
05- 51 Pegasi
06- Doppler Effect
07- Rhythmic Shift
08- Eccentric Giants
09- Transitters
10- Mu Arae
11- Intermediate World
12- Worlds Observed
13- Extra Solar Earths
14- Migrant Worlds
15- Accretion
16- Core Accretion
17- Disk Erosion
18- Planetary Embryos
19- The Protected Zone
20- Ecosphere
21- Ecosphere II
22- Beta Pictoris
23- Vanquishing Starlight
24- Red Edge / Earth Shine
25- Distant Continents
26- The Age of Stars
   

18 - Planetary Embryos

 

 

In another model Jupiters help Earths to take shape. The leftovers from the first giant gas planets to form from the disk of gas and dust provide raw material for smaller, rockier planets to form by Accretion. Gravel and rocks clump together to form hundreds of planetary embryos about the size of Earth’s moon.

Jupiter’s gravitational pull causes these planetary embryos, which would otherwise remain in their individual courses, to collide and, smashing into each other, they grow to form a handful of Earth and Mars-size planets.

This third model acknowledges the formation of the gas giants first, then rock planets later, as opposed to all the components of the system forming simultaneously - so the sequence is different. But it still builds on the understanding that they all form by Accretion, and generally fixed in their orbits.

 
  Alan Lambert 2011