Audience: 4th Grade and older.

This slide illustrates why we can easily see stars in the night sky but not their planets. The slide incorporates a graphic comparison of Brightness, Size, and Weight.

User's notes: This slide is geared toward students in 4th grade; so it uses a concrete term ("weight") rather than an abstract one ("mass") since most young students are not yet familiar with physics concepts. Weight makes sense to all kids, it's something practical, something they can converse about it; the concept of "mass" only makes sense to kids familiar with physics concepts.

NOTE: This PowerPoint file has built-in interactive elements. To view them, you must be in "Slide Show" mode; you can then move to the next view either by clicking your mouse, the spacebar, or the arrow keys. This slide will not work in "regular viewing mode."