Tools used by astronomers (au + lightyears)

Tools used by astronomers (au + lightyears)

1. Tools Used by Early Astronomers

2. Sundial Sundial: The sundial has been used for more than 7000 ​years to measure the passage of time. The merkhet uses a string with a weight on the end to ​accurately measure a straight vertical line, much like a plumb bob. A pair of merkhets were used to establish a ​north-south line by lining them up with the pole star. ​This allowed for the measurement of night-time hours as it measured when certain stars crossed a marked ​meridian on the sundial.

3. Quadrant Quadrant: was designed to measure a ​stars height above the horizon.

4. Astrolabe Astrolabe: The astrolabe was used to make accurate ​charts of star positions.

5. Cross-staff Cross-staff: was used to measure the angle ​between the moon and any given star.

6. Early Telescope Early Telescope: The telescope was invented ​in the late 16th century, it revolutionized astronomy.

7. Astronomical Units Astronomical Units (AU): is used to measure ​distances inside our solar system. 1 AU = the average distance from the center of the ​Earth to the center of the Sun (149 599 000 km)

8. Light-year Light-year: is the distance that light ​travels in one year Light travels at 300 000 km/s So 1light-year = 9.5 trillion km Interesting fact: The light from stars can take ​many thousands of years to reach us, so some of ​the stars that we see at night may no longer exist.

9. Light-year