From APOD:
Upon inspection and contemplation, a leading hypothesis for its cause has now emerged. In sum, this hypothesis holds that a lightning discharge in a thundercloud can temporarily change the electric field above the cloud where charged ice crystals were reflecting sunlight. The new electric field quickly re-orients the geometric crystals to a new orientation that reflects sunlight differently.
In other words, a lightning discharge can cause a sundog to jump. Soon, the old electric field may be restored, causing the ice crystals to return to their original orientation.

TL;DR: It was aliens.

Wow. Boston Dynamics never ceases to impress. Bipeds are useful because they are so adaptive. Further, this accomplishment demonstrates something deeper. Rather than resolving the unexpected through a more robust form factor, they've demonstrated that we can accomplish similar environmental flexibility through improvement of the control law.

Bipedal locomotion has been a holy grail in robotics for that reason. While it seems so effortless to us, it's one of the most computationally intensive things we do. It's arguably much more complex than playing chess, doing math, or any of the other metrics traditionally considered AI benchmarks.

Regarding the usefulness compared to other designs (e.g. hexapods, or treaded robots), bipeds tend to be able to maintain a higher center of gravity over a smaller base of support. That's useful in a number of tasks. Further, it isn't as if people aren't working on other robotic form factors including snakes, swimmers, flying robots, and x-apods.

Tags for this video have been changed from '5600, Saturn, Cassini, photographic, animation, fly through, photograph, space, planet' to 'Saturn, Cassini, photographic, animation, fly through, photograph, space, planet, apod' - edited by xxovercastxx

>> ^Ryjkyj:

WTF. It's not as though Hubble zooms through those things. It's just a collection of random images and video from APOD slowly being zoomed in and then getting arbitrarily cut to other completely different images. And what's with the close up of Saturn's rings at the beginning. What image is THAT based off of?
Sorry, don't mean to crap on your video but these are even terrible quality. Here:
http://apod.nasa.gov/apod/image/0805/carina07_hst_big.jpg
Now THAT's a Hubble image.


Aren't all the images "false color" anyway? Don't they doctor them to MAKE them more colorfully pleasing?

WTF. It's not as though Hubble zooms through those things. It's just a collection of random images and video from APOD slowly being zoomed in and then getting arbitrarily cut to other completely different images. And what's with the close up of Saturn's rings at the beginning. What image is THAT based off of?

Sorry, don't mean to crap on your video but these are even terrible quality. Here:

http://apod.nasa.gov/apod/image/0805/carina07_hst_big.jpg

Now THAT's a Hubble image.

>> ^Quantumwormtongue:

The Eye of God. B!tches!


Where's Mr. Frodo when you need someone to distract the eye of Sauron... err, the eye of God, sorry. I get the two mixed up -- they're both fictional villains with armies of fanatics that can't wait to usher in the destruction of the world.

The Eye of God. B!tches!

SDGundamX, unfortunately your website doesn't quite refute my own statement.

I was specifically answering the question "Why is the sky dark at night?", NOT Olbers' paradox thing.

I would agree that if the dust clouds in the Milky Way were the same temperature as the stars, they would be a lot brighter. But the simple fact is they are not. Thus they occlude the light of the stars behind them.

Because the Milky Way is stuffed full of dust which hides a huge number of stars from us, the night sky is darker than it would otherwise be to our visible spectrum, even if you don't consider the other contributing causes for darkness.

http://antwrp.gsfc.nasa.gov/apod/ap091125.html <-- proof.

You mean like this?

>> ^gwiz665:

Wow, awesome. If only there was some VOLCANO LIGHTNING too.

http://apod.nasa.gov/apod/

http://antwrp.gsfc.nasa.gov/apod/astropix.html

Fascinating how closely it resembles photos taken of the earth at night. The link between computer availability and energy consumption makes total sense and this demonstrates it perfectly. Cool video!

Nasa's Earth at Night updated October 5, 2008:
http://apod.nasa.gov/apod/ap081005.html

Thanks for the promote, bro. I hope you have a fantastic New Year too!

In reply to this comment by jimnms:
Saw this on today's APOD.

*promote

Saw this on today's APOD.

*promote

http://apod.nasa.gov/apod/ap080905.html