Images

Link	Description
Gravity Probe B and Space Time	Artist concept of Gravity Probe B orbiting the Earth to measure space-time, a four-dimensional description of the universe including height, width, length, and time.

Video

Link	Description
Apollo 15 Hammer / Feather Gravity Demonstration	Apollo 15 astronaut Dave Scott drops a hammer and a feather on the moon to demonstrate gravity.
Robot Astronomy Talk Show: Gravity and the Great Attractor	A robot crew takes a look at the Great Attractor, a massive hidden object that is pulling in every nearby galaxy in the local Universe; this does include useful background on gravity.
Testing Einstein's Universe	Written, Directed & Produced by Norbert Bartel, Ph.D., Professor of Astrophysics & Space Sciences, York University, Canada, September 2003
LIGO USA Rap	This music video pays tribute to two dozen undergraduates' summer with LIGO (Laser Interferometer Gravitational-Wave Observatory); it features the undergraduates in a rap song about the science they studied.

Animation

Link	Description
GRACE Global Gravity Animation	This visualization of a gravity model (a rotating Earth) was created with data from NASA's Gravity Recovery and Climate Experiment (GRACE) and shows variations in Earth's gravity field.

Podcast

Link	Description
365 Days of Astronomy	Why do the planets stay in orbit? And why doesn't the Moon fall out of the sky? Gravity!

Interactives

Link	Description
Gravitation 3.8	An interactive gravity modeler that can simulate a solar system, and allows you to drag the planets into new parameters; this can be used to observe gravitational interaction.
Planet Impact!	Put gravity to work as you use Jupiter for target practice.
Gravity Assist Simulator	Spacecraft often use the gravity of planets to change their speed and direction. Use this Gravity Assist Simulator to explore how these maneuvers can be used to speed up, slow down, and change the trajectory of a spacecraft.
Planet Mass Comparison	The objects in our solar system have an enormous range of sizes and masses. This animation is intended to help you compare the masses of the individual planets, our Moon, and the Sun.

Networks

Link	Description
Solar System Ambassadors	The Solar System Ambassadors is a nation-wide network of volunteers who are trained to communicate the excitement of NASA's space exploration missions and recent discoveries to people in their local communities.
Museum Alliance	The Museum Alliance is a network of museums, science centers, planetariums, observatories, parks, NASA visitor centers, nature centers, zoos, and aquariums that bring current NASA science and technology to their visitors through professional development of their staff and access to NASA staff, content and materials.
Night Sky Network	This site can connect you to amateur astronomy clubs, events, a night sky planner, and more.