# Images of the Week, January 2-6

This was a great week for images. What an amazing world we live in

I hate you, PopSci. How does a star rotate at 1 million "miles per hour?"

Also, centrifugal force? Really?

@tyronemojojohnson:
Both those statements are pretty much straight from the source (go read the linked NASA page). The way it rotates at "miles per hour" is that you mark a spot on the surface and then measure the length of time that spot takes to make one rotation. Knowing the diameter of the star and time to make a trip around the diameter, you can calculate a linear speed in terms of whatever units you want (i.e., miles per hour).

what is that layer of green in the atmosphere?

to NekoMouser: don't you mean mean circumference, even though you can calculate circumference from diameter. sorry, wouldn't think tryo would be capable to think of that.

@ tyronemojojohnson: centrifugal force? you don't believe in it? how can you not believe in inertia? why does it take more energy for a vehicle to change direction while maintaining speed than to maintain speed going straight? a force called inertia, it wants to keep the car going in the direction in which you were going, while you are trying to make it go in a new direction. hopefully you understand now. maybe you should try wikipediaing centrifugal force.

what is that layer of green in the atmosphere?

+1

In the description of the LED lamp, PopSci mis-quoted the numbers in the Gizmodo article. It takes 10 apples to power EACH LED of the 30 LED lamp. So 300 apples total.

## Popular Tags

### June 2013: American Energy Independence

Five amazing, clean technologies that will set us free, in this month's energy-focused issue. Also: how to build a better bomb detector, the robotic toys that are raising your children, a human catapult, the world's smallest arcade, and much more.

Online Content Director: Suzanne LaBarre | Email
Senior Editor: Paul Adams | Email
Associate Editor: Dan Nosowitz | Email
Assistant Editor: Colin Lecher | Email
Assistant Editor: Rose Pastore | Email

Contributing Writers:
Rebecca Boyle | Email
Kelsey D. Atherton | Email
Francie Diep | Email
Shaunacy Ferro | Email

bmxmag-ps