Exploring the Solar System: Big Sun, Small Moon (2017)

  • Exploring the Solar System: Big Sun, Small Moon activity image
NISE Network product

"Exploring the Solar System: Big Sun, Small Moon" is a hands-on activity that explores the concept of apparent size and allows visitors to experience this phenomena using familiar objects—a tennis ball and a beach ball. Participants learn that the Sun and Moon appear the same size in our sky because although the Sun is much bigger than the Moon, it is also much farther away.



Big Idea

A solar eclipse occurs when the Moon blocks the light of the Sun from hitting Earth. The Sun is much larger than the Moon, but because the Sun is so much farther away, the Moon is able to fully block it during an eclipse.

Learning Goals

We can see a solar eclipse from Earth because the Sun and Moon appear to be the same size in the sky.

The further away an object is, the smaller it appears.

NASA researchers learn new things by studying the Sun during a total solar eclipse.



This material is based upon work supported by NASA under cooperative agreement award number NNX16AC67A. Any opinions, findings, and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the view of the National Aeronautics and Space Administration (NASA).

Owning institution

The Science Museum of Minnesota

Development Process

NISE Network products are developed through an iterative collaborative process that includes scientific review, peer review, and visitor evaluation in accordance with an inclusive audiences approach. Products are designed to be easily edited and adapted for different audiences under a Creative Commons Attribution Non-Commercial Share Alike license. To learn more, visit our Development Process page.