Infinite sum of integers

You have probably seen the following video that shows that:

1 +2 + 3 + 4 + ... = -1/12

Yes; the sum of all integers from 1 to infinity it is not only finite, it is also equal to a small value, which is negative!

If you haven't yet, do watch it. Then, for clarification, you can read the links below:

• Wikipedia
• https://plus.maths.org/content/infinity-or-just-112
• Scientific American
• After Sunclipse
• What's New 

Falcon stage 1 landing is a bull's eye!

There are few interesting photos (and videos) at Space.com, showing Falcon 9 launch and landing on Dec 21st, 2015.  Make sure to take a look; they are beautiful.
I believe the one below shows a 'bull's eye', a bull's eye from hundreds of kilometers!

(Credit: SpaceX)

Playable Tortilla Record Etched with a Laser Cutter

You know you want to watch this one...

All I learned I learned from RadioLab: Speed

All I learned, I learned from RadioLab. OK, maybe not all, but many interesting facts about life, science, etc.

My favorite episode of all time is probably 'Speed'. All 'stories' in this episode are very interesting.

 

(Daniel Horowitz)