Novas and supernovas effect on our habitat

On 13 Aug, 14:24, Darwin123 wrote:
On Aug 12, 4:00*am, JT wrote:

So was there a reddish star in Sirius C (now a brown dwarf) or is it
just myth.

* * *Some references in the ancient world refer to Sirius as a red
star.
1) * * The early references to a "red Sirius" may be due to an
atmospheric effect. The observations were usually made when Sirius was
near the horizon, where optical scattering would make it look
reddish.
2) * *The references to "red Sirius" may be poetic allusions to ritual
and myth. Of course, people in those days would see it as white.
However, the red referred to perceived violence in the rituals.
3) * *The references to a red Sirius may have been true at that time.
Sirius may have changed color in recent times, going from red to
white.
* * * * I am strongly biased toward possibility number 2. This
hypothesis is presented in the book:
"The Golden Bough" by Sir James George Frazier, first published in
1922 by the Macmillan Company.
* * Frazier points out that Sirius was taken very seriously in ritual..
It's was used as an indicator of the change in seasons, to represent
the summer season. In Europe it was blamed as the deity that was
drying out the plants during the summer, sort of like a white vampire
drawing the blood out of the world. It was used as an indicator of the
Egyptian harvesting season, when red ripe crops were collected. Thus,
the references to red Sirius were symbolic.
* * "Red Sirius may actually refer to sacrifices performed to Sirius.
Frazier points out that the Romans burnt alive red haired puppies in
honor of Sirius. The idea was that Sirius was such a monster, it
needed blood colored dogs to stay alive. The early Egyptians,
according to Frazier, practiced human sacrifice to support the crops.
Thus, the rise of Sirius was a very bloody event. The Babylonians were
also afraid of Sirius as an evil deity. Sirius is a deity that has to
be appeased, not a ball of gas that has to be named.
* * The "red" would refer to the bloodiness of the rituals, not the
actual color of the star. Sirius needed blood to be satiated. Thus,
"red Sirius" would be better translated as "bloody Sirius."
* *Frazier's overall hypothesis is that magical rituals affect
mythology, rather than the other way around. He may be wrong
occasionally. His worse feature as a scholar is his neglect of
references. I have no original references to compare to his
hypothesis.
* * * Does anyone have a literal translation of some ancient text
where Sirius is referred to as red? Posting this translation could be
helpful. Was the reference an actual description by some ancient
astronomer, or a poem about the sky?
* * Also useful would be more detailed descriptions of the rituals
used to appease Sirius. Were they always done at dawn or twilight? If
so, it would be no wonder that Sirius was referred to as a red star.
At dawn or twilight, stars get this reddish look due to scattering.
Look at our sun. If the rituals were done when Sirius is high in the
sky, I would have to reject the light scattering hypothesis.
* * Ancient peoples were no better and no worse as observers than the
modern peoples. However, modern peoples also make mistakes. *Please
note that our own sun today is called a yellow star. However, if you
just look at the sun, you will see that it never appears yellow. The
term yellow refers to some details in the spectrum that our eyes are
not sensitive enough to see. So people still use imprecise language
when describing the color of astronomical bodies. One reference to
Sirius being red is not going to convince me of there being a true
color change unless there was more context associated with the
statement.

What do you think about my assertion that Sirius B's strong gravity
pull particles and gas from Sirius A and when enough mass collected a
nuclear process will make Sirius B burst up as nova again and again.

Maybe with very narrov intervalls ans maybe as recent as a couple
thousand years ago. If that is the case it will happen again and maybe
soon.

I would like a comment on the plausibility of my assertion, from
anyone who knows anything about astrophysic, but please read the text
i refered to and check if it is a correct theory about binary stars
that he propose.

JT

On 14 Aug, 11:12, JT wrote:
On 13 Aug, 14:24, Darwin123 wrote:





On Aug 12, 4:00*am, JT wrote:

So was there a reddish star in Sirius C (now a brown dwarf) or is it
just myth.

* * *Some references in the ancient world refer to Sirius as a red
star.
1) * * The early references to a "red Sirius" may be due to an
atmospheric effect. The observations were usually made when Sirius was
near the horizon, where optical scattering would make it look
reddish.
2) * *The references to "red Sirius" may be poetic allusions to ritual
and myth. Of course, people in those days would see it as white.
However, the red referred to perceived violence in the rituals.
3) * *The references to a red Sirius may have been true at that time.
Sirius may have changed color in recent times, going from red to
white.
* * * * I am strongly biased toward possibility number 2. This
hypothesis is presented in the book:
"The Golden Bough" by Sir James George Frazier, first published in
1922 by the Macmillan Company.
* * Frazier points out that Sirius was taken very seriously in ritual.
It's was used as an indicator of the change in seasons, to represent
the summer season. In Europe it was blamed as the deity that was
drying out the plants during the summer, sort of like a white vampire
drawing the blood out of the world. It was used as an indicator of the
Egyptian harvesting season, when red ripe crops were collected. Thus,
the references to red Sirius were symbolic.
* * "Red Sirius may actually refer to sacrifices performed to Sirius.
Frazier points out that the Romans burnt alive red haired puppies in
honor of Sirius. The idea was that Sirius was such a monster, it
needed blood colored dogs to stay alive. The early Egyptians,
according to Frazier, practiced human sacrifice to support the crops.
Thus, the rise of Sirius was a very bloody event. The Babylonians were
also afraid of Sirius as an evil deity. Sirius is a deity that has to
be appeased, not a ball of gas that has to be named.
* * The "red" would refer to the bloodiness of the rituals, not the
actual color of the star. Sirius needed blood to be satiated. Thus,
"red Sirius" would be better translated as "bloody Sirius."
* *Frazier's overall hypothesis is that magical rituals affect
mythology, rather than the other way around. He may be wrong
occasionally. His worse feature as a scholar is his neglect of
references. I have no original references to compare to his
hypothesis.
* * * Does anyone have a literal translation of some ancient text
where Sirius is referred to as red? Posting this translation could be
helpful. Was the reference an actual description by some ancient
astronomer, or a poem about the sky?
* * Also useful would be more detailed descriptions of the rituals
used to appease Sirius. Were they always done at dawn or twilight? If
so, it would be no wonder that Sirius was referred to as a red star.
At dawn or twilight, stars get this reddish look due to scattering.
Look at our sun. If the rituals were done when Sirius is high in the
sky, I would have to reject the light scattering hypothesis.
* * Ancient peoples were no better and no worse as observers than the
modern peoples. However, modern peoples also make mistakes. *Please
note that our own sun today is called a yellow star. However, if you
just look at the sun, you will see that it never appears yellow. The
term yellow refers to some details in the spectrum that our eyes are
not sensitive enough to see. So people still use imprecise language
when describing the color of astronomical bodies. One reference to
Sirius being red is not going to convince me of there being a true
color change unless there was more context associated with the
statement.

What do you think about my assertion that Sirius B's strong gravity
pull particles and gas from Sirius A and when enough mass collected a
nuclear process will make Sirius B burst up as nova again and again.

Maybe with very *narrov intervalls ans maybe as recent as a couple
thousand years ago. If that is the case it will happen again and maybe
soon.

I would like a comment on the plausibility of my assertion, from
anyone who knows anything about astrophysic, but please read the text
i refered to and check if it is a correct theory about binary stars
that he propose.

JT- Dölj citerad text -

- Visa citerad text -

http://iopscience.iop.org/0004-637X/...566_2_1084.pdf

On 10-08-14 02:15 AM, JT wrote:
On 13 Aug, 16:12, Yousuf wrote:
On 13/08/2010 5:25 AM, JT wrote:

Does the dust mean that Sirius B draws matter from Sirius A's
acrcretion disc?
I guess it really does not matter where it comes from but it tells
that Sirius B is fed new material, maybe this can cause it go Nova in
intervalls.

The dust in the system probably came from Sirius B itself when it died.
It's believed that Sirius A captured a lot of Sirius B's gas and dust
while it was dying, and that's why Sirius A has a lot of metallicity --
more than a star of its size should have. But when a main sequence star
like Sirius A captures gas and dust, it doesn't go nova, it just becomes
a bigger main sequence star.

Yousuf Khan

I think you misread the article Yousuf it is not the Main Star that
goes nova again and again, it is the highly gravitational white dwarf
that collect matter from the prime star. When enough matter is
collected on the surface a nuclear reaction will occur and it will
burst up in Nova.

JT

Not at all, reread my paragraph again. I'm saying that the dust came
from the white dwarf, i.e. Sirius B, just before it died. It's not
coming from Sirius A. Main sequence stars don't produce dust, dying
stars do.

There's only two events in the life of a stellar system where there is a
lot of dust in the system. The first time is when the system was first
born. The second time is when one of the stars in the system dies or is
about to die.

Yousuf Khan

On 10-08-14 02:11 AM, JT wrote:
On 13 Aug, 16:06, Yousuf wrote:
On 13/08/2010 5:13 AM, JT wrote:

Well then to my other part of questioning in the other quote, can
binary system go Nova periodically is it possible Sirius B can pick
draw matter from Sirius A and burst up as a Nova periodically again
and again?

That might happen someday, millions or billions of years from now, but
not yet. Sirius A is still in its main sequence phase, meaning that it
is tight and compact and not loose and bloated. But eventually it will
become a red giant where it would become loose and bloated, and at that
point depending on how close Sirius B is in relation to it, Sir-B white
dwarf might be able to steal gas off of the Sir-A red giant.

Well that is not how i read the article, as i understand it the
***highly gravitational*** white dwarf Sirius steals gas dust from
Sirius A accreation disc. When enough gas and dust taken there will be
a nuclear reaction on *******WHITE DWARF******** and it will flame up
going Nova.

That is why it goes nova periodically, this only happen in binary
system.

There is no evidence that anything in Sirius is going nova, you can't
believe everything some website tells you; at the very least they're
probably using old information. The two Sirius stars are at least 20 AU
apart, which is the distance between the Sun and Neptune. If you think
about how the Sun would look like from Neptune, it would look like a
very bright pinpoint, but way too far away to draw any gas from it.
Sirius A is only slightly bigger than the Sun, which still doesn't make
a difference at those distances.

You'd have to be way less than 1 AU apart to draw any gas. When the Sun
goes red giant it is expected to expand out to the current orbit of the
Earth, 1 AU. Something similar will happen to Sirius A too.

Believe me, if there was an accretion disk around one of the Sirius
stars, you'd easily know it as the disk would shine in X-rays and
ultraviolet.

Or maybe you beleive all the historical myths of a red giant star in
Sirius is simpy myth?

No, there definitely was a red giant Sirius B millions of years ago, and
there definitely will be a red giant Sirius A millions of years from
now. But nothing is red right now in that system.

Well it is not only the dogon who refer to Sirius B as a read star, i
understand that you think the story about red sirius been told by a
western antropolog.

But Sirius is a red star even in Mayan and Egyptian culture, so how
did they now Sirius once was red ***you claim*** 50 million years ago.
It seem farfetched.

As others have pointed out, there are plenty of cultural and optical
reasons why Sirius could appear to be red. All of the cultures you cited
lived close to the equator, where perhaps Sirius only appears close to
the horizon where atmospheric scattering causes a red appearance. To me,
with my naked eye I can barely make out the red color of Mars,
everything else appears to be white or yellow. The unaided human eye is
not likely the best tool for picking out colours of distant point sources.

Spectrographic analysis only shows Sirius A is a yellow-white star.
Hotter and a bit more massive than the Sun. A red star would be cooler
than the Sun. When you go towards the blue, you are getting hotter, and
when you go towards the red you are getting cooler.

I know nothing about astrology but i am rather good on put together
fact from different sources and draw new conclusion from it, to me it
seems that Sirius B really draws dust and gas from Sirius A's
accreation disc. This means we have a white dwarf that now and then
flame up in Nova.

JT

This is *not* astrology, this is astronomy, a real quantitative science.
It is fine to put together information from different sources, however
you need to verify the facts from those sources. Information from
ancient sources should be put in perspective when comparing against
modern sources. Ancients didn't have telescopes orbiting in space. Hell,
ancients didn't have telescopes, period.

It's not to say that everything the ancients said was wrong. But you
have to put in perspective what was possible back then vs. now. If an
ancient says Sirius is red, but an orbiting space telescope tells you
it's yellow. Who do you believe?

You have to award the more convincing case to the orbiting telescope.
The ancient's perspective may still be right given an atmospheric
scattering modifier.

Yousuf Khan

On 14 Aug, 19:48, Yousuf Khan wrote:
On 10-08-14 02:11 AM, JT wrote:





On 13 Aug, 16:06, Yousuf *wrote:
On 13/08/2010 5:13 AM, JT wrote:

Well then to my other part of questioning in the other quote, can
binary system go Nova periodically is it possible Sirius B can pick
draw matter from Sirius A and burst up as a Nova periodically again
and again?

That might happen someday, millions or billions of years from now, but
not yet. Sirius A is still in its main sequence phase, meaning that it
is tight and compact and not loose and bloated. But eventually it will
become a red giant where it would become loose and bloated, and at that
point depending on how close Sirius B is in relation to it, Sir-B white
dwarf might be able to steal gas off of the Sir-A red giant.

Well that is not how i read the article, as i understand it the
***highly gravitational*** white dwarf Sirius steals gas dust from
Sirius A accreation disc. When enough gas and dust taken there will be
a nuclear reaction on *******WHITE DWARF******** and it will flame up
going Nova.

That is why it goes nova periodically, this only happen in binary
system.

There is no evidence that anything in Sirius is going nova, you can't
believe everything some website tells you; at the very least they're
probably using old information. The two Sirius stars are at least 20 AU
apart, which is the distance between the Sun and Neptune. If you think
about how the Sun would look like from Neptune, it would look like a
very bright pinpoint, but way too far away to draw any gas from it.
Sirius A is only slightly bigger than the Sun, which still doesn't make
a difference at those distances.

You'd have to be way less than 1 AU apart to draw any gas. When the Sun
goes red giant it is expected to expand out to the current orbit of the
Earth, 1 AU. Something similar will happen to Sirius A too.

Believe me, if there was an accretion disk around one of the Sirius
stars, you'd easily know it as the disk would shine in X-rays and
ultraviolet.

Or maybe you beleive all the historical myths of a red giant star in
Sirius is simpy myth?

No, there definitely was a red giant Sirius B millions of years ago, and
there definitely will be a red giant Sirius A millions of years from
now. But nothing is red right now in that system.

Well it is not only the dogon who refer to Sirius B as a read star, i
understand that you think the story about red sirius been told by a
western antropolog.

But Sirius is a red star even in Mayan and Egyptian culture, so how
did they now Sirius once was red ***you claim*** 50 million years ago.
It seem farfetched.

As others have pointed out, there are plenty of cultural and optical
reasons why Sirius could appear to be red. All of the cultures you cited
lived close to the equator, where perhaps Sirius only appears close to
the horizon where atmospheric scattering causes a red appearance. To me,
with my naked eye I can barely make out the red color of Mars,
everything else appears to be white or yellow. The unaided human eye is
not likely the best tool for picking out colours of distant point sources..

Spectrographic analysis only shows Sirius A is a yellow-white star.
Hotter and a bit more massive than the Sun. A red star would be cooler
than the Sun. When you go towards the blue, you are getting hotter, and
when you go towards the red you are getting cooler.

I know nothing about astrology but i am rather good on put together
fact from different sources and draw new conclusion from it, to me it
seems that Sirius B really draws dust and gas from Sirius A's
accreation disc. This means we have a white dwarf that now and then
flame up in Nova.

JT

This is *not* astrology, this is astronomy, a real quantitative science.
It is fine to put together information from different sources, however
you need to verify the facts from those sources. Information from
ancient sources should be put in perspective when comparing against
modern sources. Ancients didn't have telescopes orbiting in space. Hell,
ancients didn't have telescopes, period.

It's not to say that everything the ancients said was wrong. But you
have to put in perspective what was possible back then vs. now. If an
ancient says Sirius is red, but an orbiting space telescope tells you
it's yellow. Who do you believe?

I argue that it had may been red and pulled mass from Sirius A but you
say it is impossible.

Well history will tell who was right and wrong.

I do not have much data but the average AU is said to be 19.8 and
closest 8 AU 1994 and 2044, but sirius B is no ordinary white dwarf
as i read about it. it have astonishing mass per cubic cm if i read
correct. and maybe there is not just the two objects that cause the
Nova.

But if you say that 1 AU is the distance for Sirius B to steal matter
from Sirius A i have to beleive you until i read otherwise.

You have to award the more convincing case to the orbiting telescope.
The ancient's perspective may still be right given an atmospheric
scattering modifier.

Well i do not have the knowledge on which distance á white dwarf is
able to pull matter from á binary star so i go with your numer 1 AU
until i find it refuted from other source.

Well anyway 2015 i guess will be the year we find out more about Novas
anyway.

JT

* * * * Yousuf Khan- Dölj citerad text -

- Visa citerad text -

On 14 Aug, 18:07, Yousuf Khan wrote:
On 10-08-14 02:15 AM, JT wrote:





On 13 Aug, 16:12, Yousuf *wrote:
On 13/08/2010 5:25 AM, JT wrote:

Does the dust mean that Sirius B draws matter from Sirius A's
acrcretion disc?
I guess it really does not matter where it comes from but it tells
that Sirius B is fed new material, maybe this can cause it go Nova in
intervalls.

The dust in the system probably came from Sirius B itself when it died..
It's believed that Sirius A captured a lot of Sirius B's gas and dust
while it was dying, and that's why Sirius A has a lot of metallicity --
more than a star of its size should have. But when a main sequence star
like Sirius A captures gas and dust, it doesn't go nova, it just becomes
a bigger main sequence star.

* * * * *Yousuf Khan

I think you misread the article Yousuf it is not the Main Star that
goes nova again and again, it is the highly gravitational white dwarf
that collect matter from the prime star. When enough matter is
collected on the surface a nuclear reaction will occur and it will
burst up in Nova.

JT

Not at all, reread my paragraph again. I'm saying that the dust came
from the white dwarf, i.e. Sirius B, just before it died. It's not
coming from Sirius A. Main sequence stars don't produce dust, dying
stars do.

There's only two events in the life of a stellar system where there is a
lot of dust in the system. The first time is when the system was first
born. The second time is when one of the stars in the system dies or is
about to die.

* * * * Yousuf Khan- Dölj citerad text -

- Visa citerad text -

Well this you certainly did read wrong, what the article says is that
Binary Systems white dwarfs may pull matter from the prime star in
this case Sirius A.

So Sirius B pull matter from Sirius A and is able to go Nova if the
star Sirius A is overflowing its roche lobe.

So please read again until you understand.. What was your 1 AU
estimated on the roche lobe?

JT

On 10-08-14 05:27 PM, JT wrote:
Well this you certainly did read wrong, what the article says is that
Binary Systems white dwarfs may pull matter from the prime star in
this case Sirius A.

If the article said Sirius B is pulling gas off of Sirius A, then it is
wrong. As I said, they are 20 AU apart, way too far to affect each other
like that. White dwarfs can pull gas off of companion stars, but they
have to be close in, and the Sirius system doesn't fit that description.

So Sirius B pull matter from Sirius A and is able to go Nova if the
star Sirius A is overflowing its roche lobe.

So please read again until you understand.. What was your 1 AU
estimated on the roche lobe?

A Roche Limit is mainly something applied to planetary bodies (i.e.
solid or liquid), not stars. It requires a rigidity factor to be
factored in, and there aren't good numbers for gaseous bodies like gas
planets or stars. The rigidity factor depends on density of the objects.

However, general rules of thumb apply and that usually means that the
two stars have to be at least within 1 AU of each other to affect each
other to the point of pulling material off of each other. Sirius doesn't
qualify. If you want to pull material off of a star at 20 AU you need at
least a galactic-scale supermassive blackhole.

Yousuf Khan

On 14/08/2010 5:21 PM, JT wrote:
On 14 Aug, 19:48, Yousuf wrote:
It's not to say that everything the ancients said was wrong. But you
have to put in perspective what was possible back then vs. now. If an
ancient says Sirius is red, but an orbiting space telescope tells you
it's yellow. Who do you believe?

I argue that it had may been red and pulled mass from Sirius A but you
say it is impossible.

Not impossible, highly unlikely. And there are more reasons than just
the distance working against this theory. A nova would be a highly
energetic event, so any light it would produce would have to be more
blue than red. Blue is hotter than yellow. Yellow is hotter than orange.
Orange is hotter than red.

Well history will tell who was right and wrong.

I do not have much data but the average AU is said to be 19.8 and
closest 8 AU 1994 and 2044, but sirius B is no ordinary white dwarf
as i read about it. it have astonishing mass per cubic cm if i read
correct. and maybe there is not just the two objects that cause the
Nova.

All white dwarfs have extremely high density, that's what makes them
white dwarfs. However, Sirius B is one of the biggest known white
dwarfs, with nearly as much mass as the Sun. If it was only 0.4 solar
masses heavier, then it would've been a neutron star rather than a white
dwarf.

But if you say that 1 AU is the distance for Sirius B to steal matter
from Sirius A i have to beleive you until i read otherwise.

That's a rule of thumb, and it's more likely it has to be even closer
than that.

You have to award the more convincing case to the orbiting telescope.
The ancient's perspective may still be right given an atmospheric
scattering modifier.

Well i do not have the knowledge on which distance á white dwarf is
able to pull matter from á binary star so i go with your numer 1 AU
until i find it refuted from other source.

Well anyway 2015 i guess will be the year we find out more about Novas
anyway.

There are much better candidates for nova watching than Sirius. Look up
the term, "recurrent nova", and especially look up the star system known
as "U Scorpii", it's already erupted several times since 1863 including
once earlier this year (1863, 1906, 1936, 1979, 1987, 1999, and 2010).
It's been observed so often, that scientists actually predicted that it
would go off sometime this year.

Yousuf Khan

On 15 Aug, 01:08, Yousuf Khan wrote:
On 14/08/2010 5:21 PM, JT wrote:

On 14 Aug, 19:48, Yousuf *wrote:
It's not to say that everything the ancients said was wrong. But you
have to put in perspective what was possible back then vs. now. If an
ancient says Sirius is red, but an orbiting space telescope tells you
it's yellow. Who do you believe?

I argue that it had may been red and pulled mass from Sirius A but you
say it is impossible.

Not impossible, highly unlikely. And there are more reasons than just
the distance working against this theory. A nova would be a highly
energetic event, so any light it would produce would have to be more
blue than red. Blue is hotter than yellow. Yellow is hotter than orange.
Orange is hotter than red.

Well history will tell who was right and wrong.

I do not have much data but the average AU is said to be 19.8 and
closest *8 AU 1994 and 2044, but sirius B is no ordinary white dwarf
as i read about it. it have astonishing mass per cubic cm if i read
correct. and maybe there is not just the two objects that cause the
Nova.

All white dwarfs have extremely high density, that's what makes them
white dwarfs. However, Sirius B is one of the biggest known white
dwarfs, with nearly as much mass as the Sun. If it was only 0.4 solar
masses heavier, then it would've been a neutron star rather than a white
dwarf.

But if you say that 1 AU is the distance for Sirius B to steal matter
from Sirius A i have to beleive you until i read otherwise.

That's a rule of thumb, and it's more likely it has to be even closer
than that.

You have to award the more convincing case to the orbiting telescope.
The ancient's perspective may still be right given an atmospheric
scattering modifier.

Well i do not have the knowledge on which distance *á white dwarf is
able to pull matter from á binary star so i go with your numer 1 AU
until i find it refuted from other source.

Well anyway 2015 i guess will be the year we find out more about Novas
anyway.

There are much better candidates for nova watching than Sirius. Look up
the term, "recurrent nova", and especially look up the star system known
as "U Scorpii", it's already erupted several times since 1863 including
once earlier this year (1863, 1906, 1936, 1979, 1987, 1999, and 2010).
It's been observed so often, that scientists actually predicted that it
would go off sometime this year.

* * * * Yousuf Khan

Well maybe i am just hooked on an idea that Sirius B going nova again
and again, if it would how big would it be in the sky? Three to ten
times our Sun i guess even bigger, or just a red star object?

JT


JT

On 15 Aug, 01:08, Yousuf Khan wrote:
On 14/08/2010 5:21 PM, JT wrote:

On 14 Aug, 19:48, Yousuf *wrote:
It's not to say that everything the ancients said was wrong. But you
have to put in perspective what was possible back then vs. now. If an
ancient says Sirius is red, but an orbiting space telescope tells you
it's yellow. Who do you believe?

I argue that it had may been red and pulled mass from Sirius A but you
say it is impossible.

Not impossible, highly unlikely. And there are more reasons than just
the distance working against this theory. A nova would be a highly
energetic event, so any light it would produce would have to be more
blue than red. Blue is hotter than yellow. Yellow is hotter than orange.
Orange is hotter than red.

Well history will tell who was right and wrong.

I do not have much data but the average AU is said to be 19.8 and
closest *8 AU 1994 and 2044, but sirius B is no ordinary white dwarf
as i read about it. it have astonishing mass per cubic cm if i read
correct. and maybe there is not just the two objects that cause the
Nova.

All white dwarfs have extremely high density, that's what makes them
white dwarfs. However, Sirius B is one of the biggest known white
dwarfs, with nearly as much mass as the Sun. If it was only 0.4 solar
masses heavier, then it would've been a neutron star rather than a white
dwarf.

But if you say that 1 AU is the distance for Sirius B to steal matter
from Sirius A i have to beleive you until i read otherwise.

That's a rule of thumb, and it's more likely it has to be even closer
than that.

You have to award the more convincing case to the orbiting telescope.
The ancient's perspective may still be right given an atmospheric
scattering modifier.

Well i do not have the knowledge on which distance *á white dwarf is
able to pull matter from á binary star so i go with your numer 1 AU
until i find it refuted from other source.

Well anyway 2015 i guess will be the year we find out more about Novas
anyway.

There are much better candidates for nova watching than Sirius. Look up
the term, "recurrent nova", and especially look up the star system known
as "U Scorpii", it's already erupted several times since 1863 including
once earlier this year (1863, 1906, 1936, 1979, 1987, 1999, and 2010).
It's been observed so often, that scientists actually predicted that it
would go off sometime this year.

* * * * Yousuf Khan

It is interesting to see how the 13th and 14the centurys black plague
also was plagued with Vaticans hunt for Necromancers and Witches,
maybe radiation toasted alot of brains, left earth with alot of numb
zoombies and they caretakers that Vatican falsly took for
necromancers.

JT