Disciplinary Core Idea (DCI)

ESS1 Earth’s Place in the Universe

• (6th-8th) ESS1.A The Universe and its Stars – The solar system is part of the Milky Way, which is one of many billions of galaxies. 
• (6th-8th) ESS1.B Earth and the Solar System – The solar system contains many varied objects held together by gravity. Solar system models explain and predict eclipses, lunar phases, and seasons.

Science & Engineering Practice (SEP) 

Developing and Using Models 

• (3rd-5th) Evaluate limitations of a model for a proposed object or tool; Develop and/or use models to describe and/or predict phenomena.
• (6th-8th) Identify limitations of models; Develop a model to describe unobservable mechanisms.

Crosscutting Concept (CCC)

Scale, Proportion, and Quantity

• (3rd-5th) Natural objects and/or observable phenomena exist from the very small to the immensely large or from very short to very long time periods. 
• (6th-8th) Time, space, and energy phenomena can be observed at various scales using models to study systems that are too large or too small.

Systems and System Models

• (6th-8th) Models are limited in that they only represent certain aspects of the system under study.