There is no gravity to hold them in place.

VOA: special.2009.06.24

Mars has less gravity. My attempts to walk resulted in jumps and hops, which took me into the air.

VOA: special.2010.07.10

Newton proved his idea by measuring how much gravity force would be needed to keep the moon orbiting the Earth.

VOA: special.2011.06.01

This most recent collision with Jupiter brought attention to how the huge planet's gravity affects our solar system.

VOA: special.2009.08.25

There was a new system of liquid nitrogen to keep the pilot cool and to resist the crushing force of gravity at high speeds.

VOA: special.2010.07.07

Because of the gravity on Mars, spacesuits may have to be designed to be lighter than suits used in orbit or on the moon.

VOA: special.2011.04.06

HeLa cells have gone to the moon to test the effect of zero gravity.

VOA: special.2010.07.21

Scientists can observe what they believe to be dark matter only through its gravity.

VOA: special.2009.07.21

Glenn explained later that at times it helped to be free of gravity.

VOA: special.2009.06.17

My muscles were used to the gravity of Earth.

VOA: special.2010.07.10

It was the debut single from his latest album,Defying Gravity, which became his first release to top the Billboard 200.

VOA: standard.2009.12.22

So the Pentagon awarded a 4-billion-dollar contract to build a version with a lower center of gravity and improved suspension.

VOA: standard.2010.08.01

And my center of gravity is a little bit lower." "I feel like sometimes it is a little more difficult to knock me down.

VOA: standard.2010.02.09

"Buildings in Jakarta are built to withstand horizontal acceleration of about and this earthquake which just happened yesterday maybe about five percent of gravity,"

VOA: standard.2009.09.07