Numbers / Angles / Astronomical Sizes

Question 1

Scientific Notation

Answer 1

uses the form: any number from 1.0 to 9.9 x 10^power

Question 2

Angular Diameters

Answer 2

shows how big an object looks, expressed as an angle.

Question 3

Use of Prefixes

Answer 3

• Kilo
• Mega
• Giga
• Centi
• Micro

Question 4

Units of Astronomical Measure

Answer 4

• Astronomical Unit (AU) is the average distance between the Earth and Sun: 1 AU = 1.496 x 10^8 km
• Light Year (LY) is the distance that light travels in one solar year: 1 ly = 9.46 x 10^12 km = 6 trillion miles
• Parsec (PC) is the distance at which 1 AU subtends and angle of 1 second of arc (1”): 1 pc = 3.25 LY = 3.09 x 10^13 km