Starship Asterisk*

neufer wrote:

Brit_in_Exile wrote:
Never ceases to amaze me when APOD throws in a line like "60 light years across". That's about 15x bigger than our Solar system which in turn means we would probably be totally unaware of it if we were in the middle of it.

Chris doesn't care how far away it is. "It could have been a million light years away."

• So, I guess, he doesn't care how big it is. (It could be 6000 light years across.)

Brit_in_Exile wrote:
Never ceases to amaze me when APOD throws in a line like "60 light years across". That's about 15x bigger than our Solar system which in turn means we would probably be totally unaware of it if we were in the middle of it.

• So, I guess, he doesn't care how big it is. (It could be 6000 light years across.)

Chris Peterson wrote:
It doesn't matter how far away it is. It could have been a million light years away and what matters is when it would have been observed.

Brit_in_Exile wrote:
I wonder what was here during the 9 - 10 Billion years before our sun formed ? I guess some bigger suns which supernova'd to produce the materials we are made of.........but anybody got better guesses (backed up by evidence)

Brian Greene Explains The Most Powerful Explosions In The Universe - YouTube

Click to play embedded YouTube video.

De58te wrote:

MaryE wrote:If light from the supernova would have reached Earth 3,700 years ago, how is it that the remnant is 7000 light years away? I didn't think the Universe was expanding that rapidly - or is it?

If I may add to the Honorable Chris Peterson comment. Light travels at a fixed speed in the vacuum of space if you remember your physics. If light from the supernova reached Earth 3,700 years ago, and the original star was 7,000 light years away then that light took 7,000 years on its journey here to Earth. So the explosion really happened 10,700 years ago in that star system (if anybody had been alive there to see it firsthand), but we on Earth between 10,700 years ago and 3,700 years ago would have seen nothing but the star shining in its prime.

MaryE wrote:If light from the supernova would have reached Earth 3,700 years ago, how is it that the remnant is 7000 light years away? I didn't think the Universe was expanding that rapidly - or is it?

sunson wrote:

ta152h0 wrote:
is the Universe we are exploring a Big Bang remnant ?

Great concept!

http://www.etymonline.com/index.php?allowed_in_frame=0&search=remnant wrote:
remnant (n.) late 14c., contraction of remenant (c. 1300), from Old French remanant "rest, remainder, surplus," noun use of present participle of remanoir "to remain". Specific sense of "end of a piece of drapery, cloth, etc." is recorded from early 15c. An Old English word for "remnant" was endlaf.

ta152h0 wrote:is the Universe we are exploring a Big Bang remnant ?

https://en.wikipedia.org/wiki/RX_J0822-4300 wrote:

[img3="The "Cosmic Cannonball" neutron star RX J0822-4300 from the Puppis A event."]https://upload.wikimedia.org/wikipedia/ ... _scale.jpg[/img3]

<<RX J0822-4300, often referred to as a "Cosmic Cannonball", is a radio-quiet neutron star currently moving away from the center of the Puppis A supernova remnant at over 3 million miles per hour (5 400 000 km/h; 1500 km/s; ~0.5% the speed of light), making it one of the fastest moving stars ever found. Astronomers used NASA's Chandra X-ray Observatory to observe the star over a period of five years to determine its speed. At this velocity the star will be ejected from the galaxy millions of years from now.

Although the cosmic cannonball is not the only hypervelocity star discovered, it is unique in the apparent origin of its speed. Others may have derived theirs from a gravitational slingshot around the Milky Way's suspected supermassive black hole, Sagittarius A*. Current theories fail to explain how such speeds can be attained from a supernova explosion. It could be a possible quark star.

However, a more recent analysis by the same group yielded a more modest recoil velocity of 672±115 km/s which is much less problematic theoretically.>>

MaryE wrote:If light from the supernova would have reached Earth 3,700 years ago, how is it that the remnant is 7000 light years away? I didn't think the Universe was expanding that rapidly - or is it?

Boomer12k wrote:Been having problems with Dark Frames with the Celestron Evolution 6. It darkens the whole image! Not just the heat speckles.

ta152h0 wrote:is the Universe we are exploring a Big Bang remnant ?