This feature article from the National Aeronautics and Space Administration's Earth Observatory discusses the use of satellite imagery to evaluate desertification which is occurring in the Sahel, a region of central African savannah that forms the boundary between the Sahara Desert to the north and the wetter, more fertile regions to the south. Topics include the use of Very High Resolution Radiometer (VHRR) data, obtained from National Oceanic and Atmospheric Administration (NOAA) meteorological satellites, to develop a vegetation index, and exactly how the term 'desertification' should be defined in order to distinguish temporarily degraded land from that which has permanently lost productivity.

This feature article from the National Aeronautics and Space Administration (NASA) Earth Observatory discusses the use of satellite imagery to evaluate desertification which is occurring in the Sahel, a region of central African savannah that forms the boundary between the Sahara Desert to the north and the wetter, more fertile regions to the south. Topics include the use of Very High Resolution Radiometer (VHRR) data, obtained from National Oceanic and Atmospheric Administration (NOAA) meteorological satellites, to develop a vegetation index, and exactly how the term 'desertification' should be defined in order to distinguish temporarily degraded land from that which has permanently lost productivity.

This is a game which focuses on the challenge of moving a "rubble pile" asteroid. Players have the option of using bombs, impactors, or "pusher" ships. It is a simpler version of Rubble! and part of the Killer Asteroids Web Site. The site also features a background overview of the differences between asteroids and comets, information on different types of asteroids (rubble piles vs monoliths), and a discussion of how at risk Earth really is to an asteroid or comet impact.

These two hands-on labs are about the role of temperature and salinity in governing the density of seawater, a major factor controlling the ocean's vertical movements and layered circulation. In the first activity students work in groups to determine the density of tap water and of tap water with salt, then compare the densities. The second activity investigates the role of temperature and salinity in determining seawater density. Students use a Temperature-Salinity (T-S) Diagram to examine the effect of mixing on density. A list of key concepts, essential questions, common preconceptions and more is included. These are part of the Aquarius Hands-on Laboratory Activities.

Learners will build an open spectrograph to calculate the angle the light is transmitted through a holographic diffraction grating. After finding the desired angles, the students will design their own spectrograph using the information learned. The activity is part of Project Spectra, a science and engineering program for middle-high school students, focusing on how light is used to explore the Solar System.

In this problem-based learning (PBL) activity, students take on the role of a student research scientist and explore the role of solar energy in determining climate, focusing on the urban heat island effect. Students conduct research and compare temperatures between two cities, and determine the factors that are responsible for the difference exhibited between them. The lesson is supported by teacher notes, answer key, glossary and an appendix with information about using PBL in the classroom. This is the third of three activities in Investigating the Climate System: Energy, a Balancing Act, and serves as an authentic assessment for all three modules.

This is an activity about creating impacts on sandy surfaces. Learners will use trays of sand and a variety of solid objects to model the effects of "impactors" on the surface. This is activity 6 of 9 in Mars and Earth: Science Learning Activities for After School.

Learners will use trays of sand and cups of water to recreate surface features seen in images of Mars. This is activity 5 of 9 in Mars and Earth: Science Learning Activities for After School.

This is an activity about modeling the effect of wind on a sandy surface. Learners will use trays of sand and straws to recreate surface features of images of Mars. Participants test their ideas about how some of the features on Mars might have been produced. This is activity 4 of 9 in Mars and Earth: Science Learning Activities for After School.

This is an activity about the periodicity of the solar cycle. Learners will calculate the number of M-class solar flares as a percentage of the total number of X-ray solar flares and graph these results as a function of time. When compared to a graph of the number of sunspots as a function of time, learners make conclusions about the period of the solar cycle. This activity uses data from the Geostationary Operational Environmental Satellite (GOES).

In this lesson, students will learn how cosmic rays were discovered and what they are - including their size and speed. Includes background information for the teacher, questions, activities and information about student preconceptions. This is lesson 1 of 4 from "The Cosmic Ray Telescope for the Effects of Radiation (CRaTER)."

The students will be able to identify questions and concepts that guide scientific investigations, recognize and analyze alternative explanations and models by the end of this activity.

This is an activity about the Hubble Deep Field image, an observation of one small area of sky that contained no previously-detected objects. The long time exposure of this image allows us to detect some of the most distant objects seen in our Universe. Learners will view an image of the Hubble Deep Field and identify how many distant galaxies are visible as well as the types of galaxies they might be. Observations will be taken a step further to infer predominant age of a galaxy and determine if there are any trends in age (color) versus galaxy size or type and, ultimately, if the distant Universe appears relatively uniform. This activity is Astronomy Activity 4 in a larger resource, titled "Space Update."

This is an online lesson which introduces the concept of astronomical filters and their connections to imaging different objects in space. Learners will explore perceptions of images as seen using different colors of light, construct a filter wheel, and practice investigating various astronomical images using the filter wheel. This material was designed to highlight how filters are useful to astronomers and show how a real astronomical telescope uses filters to image the Sun.

It is common in the real world to see mathematical examples where the cents sign was used when the dollar sign was supposed to be used. Converting and comparing decimals and fractions can help clear up this misconception. Two real coupons clipped from a Sunday paper coupon section are included in this activity. This resource is from PUMAS - Practical Uses of Math and Science - a collection of brief examples created by scientists and engineers showing how math and science topics taught in K-12 classes have real world applications.

One particular type of domino game, sometimes called the All Fives Domino game, uses multiples of five in order to score points. It can be the basis for a number of games designed to develop conceptual understanding of multiples of numbers through twelve and provide opportunities to reinforce learning objectives in a fun and competitive manner. This resource is from PUMAS - Practical Uses of Math and Science - a collection of brief examples created by scientists and engineers showing how math and science topics taught in K-12 classes have real world applications.

In this activity, students use the binary number system to transmit messages. Two flashlights are used to demonstrate how astronomy spacecraft to transmit images and other scientific data to Earth. This activity is part of Unit 4 in the Space Based Astronomy guide that contains background information, worksheets, assessments, extensions, and standards.

Students identify the actual colors of objects bathed in monochromatic light and learn how three colors of light can be combined to produce colors ranging from black to white. Students see how space observatories make use of monochromatic filters to collect data on the color of objects in space. The activity is in unit four of the "Space-Based Astronomy" guide that contains background information, worksheets, assessment activities, extensions, and alignment to national education standards.

In this activity, students simulate how light collected from a space object converts into binary data and reconverts into an image of the object. A pencil and paper activity demonstrates how astronomical spacecraft and computers create images of objects in space. This activity is part of Unit 4 in the Space Based Astronomy guide that contains background information, worksheets, assessments, extensions, and standards.

This math problem demonstrates the concept of geometric progression, through an example of a million dollar contract between an employee and an employer. Application of the concept of geometric progression to social cause activism is addressed. This resource is from PUMAS - Practical Uses of Math and Science - a collection of brief examples created by scientists and engineers showing how math and science topics taught in K-12 classes have real world applications.