1. Data

2. Observational Data Sources EM Radiation Magnetic Fields Electric fields Particles Physical/Chemical Properties Gravity

3. Data Types & Sources EM Radiation Spectral data –Received energy –Related to a material’s or process’ interaction Color Integrated spectral data useful for energy/heat flow analysis –Very simple sensors - bolometers Image data –Photographs –CCDs –Vidicons, etc. Spectral imaging data –An example is color images that are both spectral (color) and image formats

4. Data Types & Sources Magnetic Fields Measured by a magnetometer –Sensitive magnetic field detector –Many varieties –Triaxial fluxgate magnetometer very common

5. Data Types & Sources Electric fields Measures charge buildup –Planetary atmosphere including lightening –Spacecraft charge

6. Data Types & Sources Particles (atomic, molecular) Charged particles represent a potentially serious hazard to equipment and crews Charged particles can be used to identify specific materials or physical properties –Charged –Neutral –Low-energy –High-energy Many different detector types

7. Data Types & Sources Physical Properties Dust detectors Chemical analysis Radiation interaction –Alpha backscatter –Neutron activation –etc. Mechanical properties of soil, rock

8. Data Types & Sources Gravity Gravity and mass can only be measured indirectly in space –Orbital period and semimajor axis –Doppler shift of communications signal

9. Data Types & Sources Rules of Thumb More data (more instruments & sensors) is better –Allows more comprehensive models Samples, or in situ (in place) measurements, are optimal Accuracy is important to the validity of a theory