This is a Hipmunk guest post from Jodi Ettenberg. Her views and opinions are hers alone and do not represent Hipmunk. 

A galaxy that looks like a sombrero? Yeah, space has that. This image of the M104 galaxy highlights billions of old stars in its center, causing the diffuse glow of its “hat”:

And speaking of space, yesterday’s Endeavour shuttle launch was a wondrous thing to behold. NASA has posted the video of the launch, which will be Endeavour’s final mission.

When traveling around the world, tipping is always a question asked around the dinner table between travelers. Some countries don’t expect tipping unless you’re at a very high-end restaurant, others not only expect it but would be angry if you didn’t leave a tip before you leave. This handy infographic from lists out the tipping etiquette in a bunch of different countries, from the USA to Argentina to China and more.

Travel + Leisure mag rounds up the best travel gadgets for 2011 so you don’t have to.

In 1909 the great-grandfather of Flickr user Cranewoods travelled to Moscow while accompanying a group of American champion trotting horses on an exhibition tour. Cranewoods has posted a beautiful set of the vintage photos from Russia, which he interited after his great-grandfathers death.

Pretty awesome: the world’s first completely digital sundial, using no electronics or electric power. Check out the post for a detailed explanation of how it works, plus the actual blueprints to build one yourself.

I absolutely loved this Octopus ballet, a high-definition deep-sea filming of one of my favourite animals, the Dumbo octopus. Surreal and graceful, its wing-like ears propel it through the dark depths of the ocean. Lovely.

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And finally, Colombus Ohio had its 2011 Zombie Walk this weekend, and as this video shows they seem to have it under control in the event of a zombie apocalypse.

More to come later this week!