The pull of the Planets


The traction of the Planets is a 30-minute activity in which teams of children model the gravitational areas of planets top top a versatile surface. Youngsters place and move balls of various sizes and densities ~ above a plastic sheet to develop a mental picture of just how the massive of an object influences just how much impact it has on the bordering space.

This activity should be conducted after Heavyweight Champion: Jupiter!, which permits the kids to discover the force of heaviness in the solar system. These ideas involve an ext advanced scientific research than previous activities in Jupiter"s family Secrets, and also they explore an ext deeply the scientific research of the Juno mission and the rich info it will return to us. Facilitators who select to stay this activity should have actually a firm understand of the clinical basis so that misconceptions space not presented to the children.

You are watching: Which planet has the greatest gravitational attraction

This collection is appropriate for youngsters ages 10 to 13.

What"s the Point?

heaviness is the force that keeps planets in orbit roughly the Sun. Heaviness alone holds united state to Earth"s surface. Planets have measurable properties, such as size, mass, density, and composition. A planet"s size and also mass identify its gravitational pull. A planet"s mass and also size identify how strong its gravitational pull is. Models can help us experiment with the motions of objects in space, i m sorry are established by the gravitational pull in between them.


For each team of approximately 30:

For each team of four children:

1 (20" through 12" or larger) embroidery hoop miscellaneous to assistance the edges of the embroidery hoop, such together foam bricks or books 1 thin stretchable plastic sheet, prefer a plastic garbage bag or sheets the plastic-wrap 2–4 (1/2"–wide) small marbles 1 (2") Styrofoam™ ball fifty percent a have the right to of Play-Doh©

For every child:

1 pencil or pen

For the facilitator:

elevator information:


Prepare the gravity fields: large the plastic sheets (plastic plunder or garbage bags) about the inside of the embroidery hoops, then add the external hoop, maintaining the plastic stretched tightly. Set out the remainder the the materials.


1. Asking the youngsters to attach what they have actually learned around gravity come the activities of objects in the solar system.

asking the kids to recall indigenous Heavyweight Champion: Jupiter! Which properties cause a planet to have an ext or much less gravity? Planets that are massive and also have the biggest diameters have the most gravity. Which properties do not affect gravity?The existence of one atmosphere, temperature, and distance from the Sun carry out not impact a planet"s gravity. are the objects in the solar system still or space they in motion? The Sun"s gravity pulls the planets in orbit roughly it, and some planets traction moons in orbit about them. Even spacecraft space in movement through the solar system, one of two people in orbit around the planet or Moon, or traveling to additional worlds, due to the fact that of gravitational forces. The Juno mission will certainly be pulled right into orbit roughly Jupiter through Jupiter"s extreme gravity. how does gravity affect the movements of objects— such together planets— in the solar system? has anyone checked out or played v a "gravity well?" how does a "gravity well" model gravity in the solar system— what part of this version is the Sun? The planets? The center of the gravity well is the Sun, and also the coins or marbles are a model of the planets. The closer the planet is to the Sun, the greater the pull of the Sun"s gravity, and also the faster the planet orbits. This model falls short in that objects in stable orbits carry out not autumn into the Sun. (Comets are objects with orbits that have the right to easily become unstable and also fall into the Sun.)

Facilitator"s Note: There are numerous different misconceptions around gravity; kids may think the it is pertained to an object"s motion, the proximity to Earth, that is temperature, that is magnetic field, or various other unrelated concepts. Overview conversations cautiously and listen carefully to what the children say to stop supporting their misconceptions.

2. Tell the children they will make a model of how objects — choose planets — connect in space.

Have any kind of of the kids played top top a trampoline? What happens to the surface of the trampoline once you sit top top it? What would happen if a girlfriend tried to roll a ball on the surface with you sit on it?

Explain that an are can act much like the surface ar of the trampoline. The indentations make on the surface represent the "gravity wells" developed by huge objects in space.

3. Invite the youngsters to experiment through the same effects on smaller–scale models. Separate the children into groups and give each group a ready embroidery hoop, exposed in the air on bricks or books. Explain that castle will usage marbles and Play-Doh balls to design the effects of gravity on objects in space.

What will happen to the plastic sheets (space) if they include a marble to it? It will stretch out and also the marble will certainly roll. What will take place if there room two marbles top top the sheet? The marbles will roll towards each other.

Facilitator"s Note: heaviness is a universal force, prefer magnetism and electricity. However, that becomes important only at large scales. Heaviness determines the interaction stars, planets, and moons.

In the model, the balls are too tiny to exert a far-reaching gravitational pull on every other. However, they room gravitationally pulled toward Earth! They relocate toward each other due to the fact that the weights of heavier objects distort the sheet and lighter objects roll "downhill."
4. Invite the children to experiment through their models of space by placing and dropping the marbles (together and also separately) onto the sheet.

5. Questioning the groups to each include a large, 2" round ball of Play-Doh to stand for a huge "planet" alone on the sheet. questioning the children to hypothesize what will occur if the marbles are dropped top top the sheet, and have them record their thoughts in their journals before they check them. ~ they have dropped the marbles onto the sheet, share the this "pull" towards the "planets" is a model of gravity.

just how does this version gravity? The marbles are pulled, or "fall," toward the planet. does this huge Play-Doh planet represent solid or weak gravity? This world has strong gravity— the marbles fall straight toward it.

Facilitator"s Note: The Play-Doh and also Styrofoam balls provided in procedures 5–7 serve to produce test "wells" ~ above the sheets. They need to remain stationary if the children roll the marbles come see how they relocate at each step. Encourage the kids to only roll marbles, together the Play-Doh is sticky and will not model the activity accurately.

6. Asking the groups to location a very small round sphere of Play-Doh (about half of the dimension of a marble), which represents a small asteroid, alone on the sheet. Have them note their predictions in your journals and also then check what will take place to marbles included to the sheet.

What will happen if marbles are added to the sheet now? Why? The marbles may take longer to with the Play-Doh asteroid or may not relocate toward it at all. What kind of gravity will certainly a small asteroid have contrasted to a large planet? It doesn"t have very much "gravity".

7. Questioning the teams to place the Styrofoam round alone on the paper and, keeping records in your journals, experiment v its gravitational pull.

What kind of object might the Styrofoam sphere model? It have the right to represent a earth that isn’t really dense, favor Saturn. exactly how does its size, mass, and also density to compare to that of the huge Play-Doh "planet"? It is around the exact same size, but less dense and also therefore much less massive. What will take place when the marbles are added? will they behave an ext like they did because that the big or small Play-Doh planets? Again, the marbles may take much longer to reach the low-density huge planet; lock won’t feel the traction of gravity as strongly together they did v the very huge Play-Doh planet. Does Saturn have as lot gravity as Jupiter? Saturn’s gravity is not very solid compared to Jupiter’s.

Remind the kids that the gravitational traction of a planet depends top top its mass and also size. Saturn is huge in size, however it does not have virtually as lot mass packed right into its volume together Jupiter does.

Facilitator"s Note: Saturn does have actually plenty the mass, and also as they discover in Heavyweight Champion: Jupiter!, that does have gravity. However, due to the fact that it is no dense, a human being standing in its cloud top would only weigh around as much as they sweet on Earth. Saturn"s cloud tops space far above the planet"s bulky — and gravitationally solid — center.Because the force of gravity depends on both mass and distance, planets that space puffy and less dense have less gravity at your cloud-tops or surfaces, which space far over the bulk of the fixed in your interiors. This is why planets choose Saturn show up to have less gravity than Neptune, in spite of Saturn"s higher mass. You might need to remind the kids of what castle learned in Dunking the Planets in order for them to understand these complicated concepts.

8. Invite the groups to experiment through dropping the marbles in different locations, and also with different amounts of Play-Doh or the Styrofoam ball, in various places on your gravity field.

perform the marbles ever before briefly circle the planet? do they ever before avoid the planet? Do tiny asteroids endure gravity? Asteroids and other little bodies, prefer comets, are also kept in orbit around the sunlight by the Sun"s big gravitational traction — also when they space at good distances from the Sun. Castle can also be pulled right into orbit around a earth — choose Mars" two moons— or influence a moon or planet.

9. ~ the youngsters have finished experimenting, talk about their findings.

just how did the marbles behave toward the largest Play-Doh planet? They rolled straight toward it. How was this favor gravity? The large planet had actually a many mass, and, in our model, a most gravity. how did the marbles behave with the Styrofoam planet? They may have actually ignored that completely. Why? The round did not have much mass, and so it had actually very small gravity in this model. go a huge object always have a lot of mass? No! If we can measure the gravity of a planet, and also its size, what can that call us around that planet? The gravitational pull of the planet have the right to tell us more about the planet"s mass, which helps us to recognize its density and also what its interior is like.

Ask the kids to attract in your journals, based upon their models, how deep a heaviness well the Moon, Earth, and Jupiter each create in space. Have them define how their differences in gravity relate to each object"s size and mass.

10. Invite the children to describe how this design of gravity resembles actual gravity and just how it fails.

do objects in the solar mechanism move toward each other with actual gravity, like they go in the model? Yes. execute objects roll toward each various other in an are because the gravity? No, they are tugged yet they don"t roll. do planets in our solar mechanism usually run into each other? No, they are really far apart and they are orbiting the Sun. Occasionally comets and asteroids collide through planets, though.

Facilitator"s Note: Children also may not recognize that the planets space not being considerably pulled towards each other. They room strongly pulled toward the Sun, but because they are likewise moving, castle move approximately the sun in steady orbits. Smaller objects prefer comets and asteroids may have less circular orbits that cross the courses of planets — sometimes resulting in a collision. Be cautious when identifying the objects in this activity not to introduce misconceptions concerning planets" orbits and also collisions.


Explain the the Juno mission come Jupiter will suffer Jupiter"s heaviness in much the same method as a very, very little marble can in our model.

See more: Merry Christmas And Happy New Year In Tagalog ? Merry Christmas In Tagalog

show a picture or video clip animation that Juno orbiting Jupiter. (Juno will certainly orbit Jupiter, however, fairly than falling into it.) Juno"s instruments will keep mindful track of exactly how Jupiter"s traction on the spacecraft alters as the spacecraft passes end the planet"s surface. In this way, Juno will be able to measure just how Jupiter"s heaviness is various from place to place. By measure up the slight changes in Juno"s trajectory, scientists will find out where precisely Jupiter keeps the mass of its fixed in the deep interior. Scientists deserve to then infer details around the composition of Jupiter"s unseen lower layers and also core.

How strong a pull will Juno feel as it orbits Jupiter? A very strong pull!

If possible, develop on the children"s knowledge by providing them a future Jupiter"s household Secrets activity. Invite the children to go back to wrap-up their investigations that Jupiter by attending the concluding activity, My pilgrimage to Jupiter, where they develop scrapbooks to record their very own journeys into Jupiter"s deepest mysteries!