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the losses you're in the northern crown
welcome stargazers
and in re guess astronomer from the
Cincinnati Observatory
and I'm James all very director the key
cassava pop planetarium in Gainesville
Florida
this week we're gonna show you one of
the most exquisite little constellations
in the summer sky
and its easy to find if you have fairly
dark skies
and you're away from city lights and you
use our
old arc to work to restrict what are we
talking about
let's show you okay we've got our skies
set up for this week between nine and 10
p.m.
your local time if you look to the
northwest you find our old friend the
Big Dipper
using our old trick drawing an imaginary
line
following the archive the dippers handle
we will art to the closest bright star
our terrace remember arc tartars then
instead of continuing that arc to speed
on to spike a in the constellation Virgo
or simply hang a right at arc to risk
and then look slightly
East a bit for the star alpaca affect is
not nearly as bright as arc tourists
but it's the brightest star in its part
in the sky affect is the brightest star
and a half circle stars we call Corona
borealis
the northern crown at this time here
Corona borealis is almost directly
overhead between nine and 10 p.m.
the reason of ECA so much brighter than
the other stars in the crown
is because it is so much closer to us
the star is
only 75 light years away now
although alf ECA is a lovely star in the
crown there's a far more
interesting one it's called T Corona
borealis
or more popularly blaze Starr almost 150
years ago something very peculiar
happened to the star
most of the time T Corona borealis is so
damn
they can only be seen through a
telescope however
just one year after the ended the Civil
War on may twelfth
1866 astronomers solve the star
erupt into such blazing brilliance by
the
end of the night it was actually
brighter the brightest star in the crown
alf ECA amazed by this incredible
outburst
astronomers calculated that its light
had increased twenty-five hundred times
by the next night and are already begun
to fade and just one week later
it was once again invisible to the naked
eye what in heaven's name happened to it
and would it ever be seen again well the
answer to that question is yes
but it wouldn't be seen again by those
who had originally witnessed
eighty years later on February 9th 1946
T Corona borealis flared up again
although the astronomers a
1946 didn't understand the complete
picture
they were able to determine that the
outer layers have the star
had exploded and we're expanding away
from the star
generate over 2700 miles per sec
later study showed that while the
brightest star in the crown
a factor was only 75 light years away
take roddenberry alice is over 2600
light years away
which meant that for to become even
brighter than of ECA
it would have had to have blazed in just
a few hours time
from its normal fifty times brighter
than our Sun to over 200,000 times
brighter than our Sun
so what could cause this well
astronomers now know that T Corona
borealis
is actually two stars a giant red star
with a blue white dwarf companion as the
stars
orbit each other gas is gravitationally
exchange between the two
every so often the super hot dwarf star
reaches a critical level of gas
collected from the cool red giant star
its outer layers have gas
violently explode and fling their
material through out the heavens
causing the dwarf star to become
thousands of times brighter
in just a few seconds and then after the
gases shed
the star quickly dims back to its normal
invisible to the naked eye brightness
and the whole flow process of
accumulating guess to yet another
critical level begins
astronomers call this a recurrent Nova
so the question is
will the Los jewel in the crown teak
roddenberry of Brighton again in our
lifetime
well we have to wait until 2026 to see
it again
who knows but one night if you're lucky
you may see the loss in June love the
northern crown blazing away
in all its brilliance for one brief
night and one night only
if you simply remember to heap looking
up
ok