Oh chem lab how I don't miss you.

Looks identical to http://videosift.com/video/25-003-teddy-bears but from a different angle. Dupe?

Old hat.

"We cannot observe supernova remnants across our entire galaxy – basically nebulae. Supernova events we can see across the visible universe, but the actual gaseous remnants are much fainter because they are more diffuse. Because of dust and gas in the way, we cannot see all the objects in our own Galaxy. Probably the farthest we can see into the galaxy is maybe to a distance of 10,000 light-years. The galaxy is about 100,000 light-years across. Doing a simple calculation of the area of a disk 10,000 light-years vs. 100,000 light-years (but 50,000 light-years in radius) yields an area of our galaxy about 25 times larger that we can NOT survey for supernova remnants vs. what we can.

So now, we need to multiply our 10,000 years by 25, giving us 250,000 years for the age of the galaxy.

The next part is that supernova remnants don’t just form out of nothing, they form from the explosions of dying stars. The stars that live and die the fastest still take about 10,000,000 years before they “go nova” and release a cloud of debris that will later become what we observe. That’s pretty much the minimum time a star can “live” during the current epoch of the Universe. Only after that will we see a supernova form.

So, add that to our estimate of the age by the number of stars and we have 10,250,000 years, or 10.25 million years for the age of the galaxy. You should note at this point I’ve been saying “age of the galaxy.” That’s because this would only be used to date our galaxy, not the Universe as a whole. So you need to add in the time for galaxy formation … which is still a number that’s hotly debated, but no respected astronomer will say happens instantaneously.

BUT, there’s another complication to this situation which shows why this apparent “method” for dating our galaxy isn’t valid: Supernova remnants fade! They only are visible for a few tens of thousands of years. What does this mean for our estimate of 1,000,000 years for the age of our galaxy? Well, by the time the “oldest” supernova is fading, we starting to observe supernova 200! We should only expect to see in the neighborhood of a few hundred supernova remnants in our vicinity, regardless of how old our galaxy actually is."

*dead

This man manages to turn something so incredibly fascinating into something so incredibly boring. Some people just don't have the gift of gab, I guess.

*promote

lol this guy is hilarious.

But bananas biodegrade.

Have had this for our kitty for about a year now. She no longer gives a shit about the ball - just uses it to scratch on.

*related http://videosift.com/video/How-to-properly-sharpen-a-pencil

*promote

>> ^PlayhousePals:

That was awkward. Reminds me of something that happened to me once [shudder] =o/


Aw are you somebody's wolf cub?

Good job, PHP! You're clearly better than me. Clearly!

I have a mustache and I approve this message.

How hard is it to buy a cheap pair of elbow and knee pads? Seriously idiotic.