Many scientists believe it is dark matter but some also believe it is gravity
Gravity
Gravity.
The force of gravity keeps the Earth (and all the other planets) orbiting the Sun.
gravity is the force that keeps us on earth.
the name of the force iis called gravity or its gravitational pull
Isaac Newton
sellotape
That would be GRAVITY
Cohesion.
Gravity I believe. If not, try orbitity.
It can be. A centripetal force is not fundamental (such as gravity), it is the generic name given to a force that keeps objects moving in orbits (or circles). In the case of the Sun and the Earth, gravity is the centripetal force that keeps the Earth in orbit around the Sun.
Nebulae are the birth places for stars, not planets. However, once stars begin to form, planets can come about through gravitational 'clumping' in the stellar accretion disc.