Astronomers See Historical Supernova from a New Angle

[n2doc]

ScienceDaily (Mar. 31, 2010) — Since Galileo first pointed a telescope at the sky 400 years ago, a myriad of technological advances have allowed astronomers to look at very faint objects, very distant objects, and even light that's invisible to the human eye. Yet, one aspect usually remains out of reach -- the benefit of a 3-D perspective.

Our telescopes show the Milky Way galaxy only as it appears from one vantage point: our solar system. Now, using a simple but powerful technique, a group of astronomers led by Armin Rest of Harvard University has seen an exploding star or supernova from several angles.
"The same event looks different from different places in the Milky Way," said Rest. "For the first time, we can see a supernova from an alien perspective."

The supernova left behind the gaseous remnant Cassiopeia A. The supernova's light washed over the Earth about 330 years ago. But light that took a longer path, reflecting off clouds of interstellar dust, is just now reaching us. This faint, reflected light is what the astronomers have detected.

The technique is based on the familiar concept of an echo, but applied to light instead of sound. If you yell, "Echo!" in a cave, sound waves bounce off the walls and reflect back to your ears, creating echoes. Similarly, light from the supernova reflects off interstellar dust to the Earth. The dust cloud acts like a mirror, creating light echoes that come from different directions depending on where the clouds are located.

http://www.sciencedaily.com/releases/2010/03/100331104925.htm

[byronius]

1. ohthatissocool.

[JoshieR]

2. Thinking about this stuff...

...just boggles my mind. Like, when you get to the "edge" of the universe, what's there? If the universe is closed and is spherical, what is outside the sphere?

It's enough to make you go cross-eyed!

[Chulanowa]

3. Oh, that one's easy!

It's turtles, all the way down

[Cronus Protagonist]

4. The universe is inside the "light cone" and we cannot know what's outside of it

Although recently, there have been detections of gravitation influence coming in from outside the light cone, which indicates that there may actually be evidence of something there.

Still, we cannot observe anything outside the light cone directly due to the limitations on the velocity of light. We can only see where the light of the big bang had traveled, we cannot see what is outside of that light, since no light has reached there yet for us to be able to discern it. The term for anything outside the light cone is "superluminal" and I personally think it would be foolish to presume that the universe fits completely within the light cone.

By the way, the current thinking is that the universe is relatively flat and will therefore not collapse in on itself and will therefore suffer heat death in the distant future when entropy gets its way.

[meeshrox]

5. Read that on NASA's website the other day... (flat universe)

I was looking for the infinite multiple universe theory and got stuck on that instead! I had a hard time explaining it to my hubby, he did one of those Lewis Black eyecrosses and fell over! Finding that info was so great! I would love to hear more on that from Mr. Hawking!

http://map.gsfc.nasa.gov/universe/uni_shape.html

:we need a drooling icon:

[meeshrox]

6. Ooohhhh! That is crazy!

Never thought of that techinique...sooo interesting!

[Odin2005]

7. COOL!