The Crab Nebula

We all read that there was a day the sun stood still. It might have been
days that there was no "dark" night sky. It had to be the biggest
explosion ever witness by mankind. Still talked about after 1054 as
recorded by Chinese astronomers. The Crab Nebula is still expanding(over
coming gravity) at our present time. I wonder how many H-bombs
explosions it would take to equal that supernova explosion? How
much dark matter that was created and blown through space? Did it leave
at its core a blackhole or a neutron star from the implosion?
Astronomers only talk about the 100 odd chemical elements created by the
supernova explosion being in the form of dust particles. Could some be
bigger than dust and be as big as a small rock planet,say the size of
our moon? Some how I see comets can give answers to some of my
thoughts. When those aerogel panels come back to Earth with captured
comet dust (comet Wild-2) it might have the right stuff to give us the
right answers. Bert

(G=EMC^2 Glazier) wrote in
:

We all read that there was a day the sun stood still. It might have
been days that there was no "dark" night sky. It had to be the
biggest explosion ever witness by mankind. Still talked about after
1054 as recorded by Chinese astronomers. The Crab Nebula is still
expanding(over coming gravity) at our present time.

It was about four times brighter than Venus - still no where near as
bright as the full moon, so forget the no dark night sky stuff.

http://www.seds.org/messier/m/m001.html


I wonder how many H-bombs
explosions it would take to equal that supernova explosion? How
much dark matter that was created and blown through space? Did it
leave at its core a blackhole or a neutron star from the implosion?

A pulsar (rapidly rotating neutron star) appears to be the remnant. No
dark matter apart from neutrinos would have been produced.



Astronomers only talk about the 100 odd chemical elements created by
the supernova explosion being in the form of dust particles. Could
some be bigger than dust and be as big as a small rock planet,say the
size of our moon?

No. Think about it.

SNIP

L.

Well 4 times brighter than Venus plus the light of the moon might have
caused night stark shadows. People do go over board in their
thinking over long time lapses. Still the light of that supernova
explosion was seen during the day. How can we be sure how bright it was
without being there?. It had to be a bit scarry in those ancient times.
Bert

(G=EMC^2 Glazier) wrote in news:16430-3FC27A23-
:

Well 4 times brighter than Venus plus the light of the moon might have
caused night stark shadows. People do go over board in their
thinking over long time lapses. Still the light of that supernova
explosion was seen during the day. How can we be sure how bright it was
without being there?. It had to be a bit scarry in those ancient times.
Bert


As far as I know, the brightness estimate is based on the reports of the
Chinese observers. Venus is actually visble during the day when well
separated from the sun.

http://www.fourmilab.ch/images/venus_daytime/

To see it, you have to completely block the Sun from the view. WARNING -
if you attempt this, be extremely careful. Especially if you are using
any optical aid to initially locate the position of Venus.

Rgds Llanzlan.

Hi Rgds I find that interesting that Venus can be seen in day light,if
you know where to look. I think I read(long time ago) that this
supernova explosion's light lasted for two weeks. Was that the length of
the explosion? I would think being an explosion the light would
only last a second,especially since the supernova is surrounded by just
the vacuum of space. Could these great explosions disrupt the fabric of
space? I'm working on a theory that space creates inertia,and it could
fit in here nicely. Its on the lines of Mach thinking Bert

(G=EMC^2 Glazier) wrote in
:

Hi Rgds I find that interesting that Venus can be seen in day
light,if you know where to look. I think I read(long time ago)
that this supernova explosion's light lasted for two weeks. Was that
the length of the explosion?
I would think being an explosion the light would
only last a second,especially since the supernova is surrounded by
just the vacuum of space.

With a type II supernova that forms a neutron star via collapse, you
have a pretty complex situation. The neutron star is very small compared
to the original star and initially will be furiously oscillating. Theory
says that these oscillations would damp out rapidly via gravitational
radiation (the LIGO experiment is currently trying to detect such
radiation from such a collapse event - no nearby type II's have occurred
since LIGO has been running though). The neutron star will also have an
enormous temperature (billions of degrees). It gets rid of a lot of this
energy by neutrino emission and eventually normal thermal radiation from
its' surface. In the mean time the outer layers of the star get blown
off by a gigantic shock wave which also causes all sorts of nuclear
reactions to take place. The debris glows brightly from thermal
radiation and it is also being pumped with additional energy from
radioactive decay. The debris doesn't reach its peak brightness in the
optical spectrum until quite a while after the actual blast. The debris
continues to glow and expand for thousands of years after the supernova.
That is why we can still see the crab nebula today.

Could these great explosions disrupt the fabric of
space? I'm working on a theory that space creates inertia,and it could
fit in here nicely. Its on the lines of Mach thinking Bert


That isn't a theory. You need to do a bit of learning.

Llanzlan.

Hi Klazmon Nicely done. This great radiation must heat up space. We
measure the micro waves having a temperature of 2.7K What would space
temperature be say 5 LY from such a great explosion? I ask this because
I read about the supernova explosion in 1987,and it had two rings of
expanding gas having diameters that are very large. A few month's ago
I was told that Eta Carinae is not the most massive or brightest star in
our galaxy. That the Hubble using its infra-red vision had found a more
brilliant star close to the core of our galaxy.(25 thousand LY away.
This colossal star is shinning with the intensity of about 10 million
suns. Could that massive star be ready to explode? How would this
explosion effect our solar system? Could our galaxy have
multi-blackholes? Could supernova explosions make sure that no life in
the universe can last more than 25 million years(scary thinking) for
that only gives the life on earth about another 20 million years to go.
I'm naturally talking intelligent life. A supernova explosion in our
galaxy can show life in the galaxy how fragile it is. With only 20
million years to go I would think mankind should start thinking of
packing up and finding a safer area of the cosmos. Bert

"G=EMC^2 Glazier" wrote in message
...
multi-blackholes? Could supernova explosions make sure that no life in
the universe can last more than 25 million years(scary thinking) for
that only gives the life on earth about another 20 million years to go.
I'm naturally talking intelligent life. A supernova explosion in our
galaxy can show life in the galaxy how fragile it is. With only 20
million years to go I would think mankind should start thinking of
packing up and finding a safer area of the cosmos. Bert
On the subject of life, intelligent life.

Maybe the reason that we humans seem to be alone is that we are alone...at
this time. The visible universe is so vast that intelligent life has almost
certainly evolved many times in the past. After all, it happened here so it
is possible, given the right conditions. However...maybe intelligent life
*does* keep popping up all over and then promptly gets extinguished again by
nearby events such as supernova explosions.

Does anybody have any guesstimates of how common these life extinguishing
events might be? Maybe it is just an unfortunate fact that they are just as
common, or more common, than the appearance and evolution of life. I hope
not.

Sally

Hi Sally That was my point. Supernovas because they are stars so big
and dense have only 25 million years before they collapse and explode.
Their radiation can be seen 8 billion light years away by the Hubble.
Having a star that is close to our galaxies core (brightest and most
massive in the Milky Way) and only 28 thousand LY away could end all
life in our galaxy. Well Sally I believe there is lots of life in the
universe. I believe there is lots of water in the universe. I believe we
live in the best of spacetime,more stars like our sun than any other
kind. More galaxies like the Milky way. Life in the universe
came from supernova explosions,and supernova explosions that are to
close can wipe out this life. Bert

Unlike the "Coast to Coast" radio show, in astronomy what you can
demonstrate with empirical evidence is far more significant than what you
"believe."

"G=EMC^2 Glazier" wrote in message
...
Hi Sally That was my point. Supernovas because they are stars so big
and dense have only 25 million years before they collapse and explode.
Their radiation can be seen 8 billion light years away by the Hubble.
Having a star that is close to our galaxies core (brightest and most
massive in the Milky Way) and only 28 thousand LY away could end all
life in our galaxy. Well Sally I believe there is lots of life in the
universe. I believe there is lots of water in the universe. I believe we
live in the best of spacetime,more stars like our sun than any other
kind. More galaxies like the Milky way. Life in the universe
came from supernova explosions,and supernova explosions that are to
close can wipe out this life. Bert