Astronomical Units and Terranes

Space Units and Intro to Terranes

What is an astronomical unit?

Written as "AU"

The distance from the Sun to the Earth and is used to measure larger measurements of space.

One astronomical unit or 1 AU is 150,000,000 km

Multiple Choice

If an object is 4 AU away, which of the following statements is correct?

• The object is 1,000,000 km away

• The object is twice the length of the distance between the sun and the earth away

• The object is 400,000 km away

• The object is four times the length of the distance between the sun and the earth away

Let's Do Some Math!

• You may work alone or you may work in pairs.

• Calculate how many kilometers away each planet and dwarf planet is from the Sun.

• Remember, ONE AU = 150,000,000 km

What is a light-year?

The first thing to understand is that LIGHT IS THE FASTEST THING that has ever been measured.

What is a lighttyear?

A light-year is written as: LY

A light-year is a DISTANCE measurement, not a time measurement.

**It is the distance light travels in one year.**

Light travels at 299,792,458 meters per second (or to do some quick math, approximately 300,000 km/s).

Multiple Choice

A lightyear is a measurement of...

• Time

• Distance

• Neither

Whoa...

• That’s very fast. If you could travel at the speed of light, you would be able to circle the Earth’s equator about 7.5 times in just one second!

• A light-second is the distance light travels in one second or 7.5 times the distance around Earth’s equator. A light-year is the distance light travels in one year.

• But how far is that?

How far is that?

• How do you think we would calculate that?

• Multiply the number of seconds in one year by the number of miles or kilometers that light travels in one second.

Make sure make sure to get these down in your notes!!

Let’s get some practice!

Zoomies, check your email for an email from me! You will need to email me a copy of your work.

INSTRUCTIONS FOR EVERYONE

1. Read the notes on the worksheet.

2. ON A SEPARATE PIECE OF PAPER IN YOUR NOTES, do “calculate 1,” “calculate 2,” and “calculate 3” on your own.

3. Collaborate with a buddy to see if you got the same answers.

4. Answer the comprehension questions IN COMPLETE SENTENCES.

But exactly how big is that number?

Copy and paste this into your Internet browser.

https://htwins.net/scale2/

1. Explore the program

2. Be ready to share three things you thought were cool on the board