What is Dark Matter?
Dark matter is a type of matter that does not emit, absorb, or reflect light, making it invisible to telescopes and other instruments that detect electromagnetic radiation. It is also different from ordinary matter, such as the atoms that make up stars, planets, and living organisms.Evidence for Dark Matter
Scientists have observed the gravitational effects of dark matter on the motions of galaxies and galaxy clusters. They have also studied the bending of light around massive objects, a phenomenon known as gravitational lensing, which provides indirect evidence for the presence of dark matter.Composition of the Universe
The universe is composed of approximately 5% ordinary matter (the stuff we can see and interact with), 27% dark matter, and 68% dark energy. Dark energy is another mysterious component that is responsible for the accelerating expansion of the universe.Study Guide
- What is dark matter?
- How is dark matter different from ordinary matter?
- What evidence supports the existence of dark matter?
- What is the composition of the universe in terms of ordinary matter, dark matter, and dark energy?
Exploration and Research
.◂Science Worksheets and Study Guides First Grade. Weather
Study Guide
Weather 
Activity Lesson
Weather Worksheet/Answer key
Weather Worksheet/Answer key
Weather Worksheet/Answer key
Weather Worksheet/Answer key
Weather Vocabulary/Answer key
Weather Vocabulary/Answer key
Weather
Activity LessonWorksheet/Answer keyWorksheet/Answer keyWorksheet/Answer keyWorksheet/Answer keyVocabulary/Answer keyVocabulary/Answer keyThe resources above cover the following skills:
Earth Systems Science
Earth's materials can be compared and classified based on their properties. Students can:
Identify and represent similarities and differences such as the texture, size, color, and shape of various materials on Earth