1. Astronomer’s Tools Discovery Through Technology

2. Humans have created many tools to help explain the mysteries of the universe. Sun dials  help tell time each day

3. Merkhet to chart astronomical positions and predict the movement of stars Quadrant Measures stars height above the horizon

4. Astrolabe Make accurate charts of Stars Cross-staff Measures angle between the moon and any given star

5. Telescope Study planets and stars Today, super-powerful optical and radio telescope’s operating from earth, satellites orbiting around Earth, and sophisticated space- based telescopes have shown us the immensity of objects in space and of distances across the universe.

6. Astronomical Units (AU)  Used to measure distance in our solar system  One AU is equal to the distance from the center of Earth to the center of the Sun (149 599 000 km)

7. Light Years  Used to calculate distances outside the solar system  It equals the distance light travels in one year (300 000 km/s = 9.5 trillion km) If you wanted to wind a string 1 Light-year long around Earth’s equator, you would have enough string to wrap it around 236 million times! Light from the sun takes about 8 minutes to reach earth Ancienct Myia(45 min)