What is the IAU?

• International Astronomical Union

• Iowa-Altoona University

• International Astrological Interpretation

• Internal Astronomy Units

Why was the Astronomical System of Units developed?

• Because astronomers hated the Imperial measurements

• So scientists can feel special

• Standard measurements were too small to effectively measure space objects

• Because scientists are incredibly lazy and the ASU is easy

THe Astronomical System of Units measures three things. ​ (a)   ​ ​ (b)   ​ (c)  

• Time
• Mass
• Distance
• Weight
• Density
• Angle
• Volume

This standard measurement is 86,400 seconds long and is the time it takes for Earth to rotate once on its axis

• Year

• Month

• Week

• Day

It takes Neptune 165 of these to revolve around the Sun, but it only takes Earth one of these to complete a revolution around the Sun.

• Decade

• Year

• Month

• Century

Tags

NGSS.HS-ESS1-4

NGSS.HS-PS2-4

Match the following time measurement to its converted length

• 365.25 days

• Year

• 86,400 seconds

• Second

• 29.5 days

• Day

• Fine decay of a Caseium-133 atom

• Month

Match the following distance measurements to what they measure

• Orbiting objects like satellites

• Lunar distance

• Near-Earth Objects

• Kilometers

• Anything further than the solar system

• Light-year

• Solar system objects

• Astronomical Unit

• Solar Mass

• Earth Mass

• Lunar Mass

• Jovian Mass

You've discovered a rocky exoplanet! Which unit of measurement should you use to compare its mass?

• Jovian Mass

• Earth Mass

• Boston Mass

• Solar Mass

Gas and Ice Giants are generally FAR larger than their rocky cousins. Which mass would you use to measure them?

• Elsa Mass

• Solar Mass

• Earth Mass

• Jovian Mass