There's a flaw in the premise here: hundreds of other systems have been detected. However, the information available about just one (our own) is sufficient to speculate on genesis.
Aristarchus of Samos
Scientists theorize that a planet-sized object collided with earth to form the moon.
big bang: This is the big bang theory
Scientist theorize that a planet-sized object collided with earth and the moon formed
Well , I'm guessing this is for your homework considering I used it for mine haha , but the answer is Jupiter's Gravity .
theorize
"I theorize you will soon register and have a real user name." "Experiments with alpha particles led Rutherford to theorize that most of the mass of an atom was concentrated in a small area, the nucleus."
scientists theorize that it was jupiters gravity that kept it from forming
Democratic is the enlightenment the theorize. This was thought up by John Locke.
Scientists theorize that higher global temperatures are do to the greenhouse effect.
Hypothesize.
Speculate
To try and make sense out of this world.
Pythagoras
Pythagoras
The verb for thinking up a theory is "to formulate."
PYTHAGOREANS