well howdy.
firstly, camping.... didnt think it was too shabby for something we threw together in an hour :P all gurd :)
and gwyn touched a chicken in the end...bravo gwyn
yeah, anyways, i have a friend who has recently been asking me alot about black holes and the threat they pose to us: since ryan wont accept my answer of, 'NONE WHATSOEVER right now'.... i've had to go into some details.
the big one!
firstly, scientists believe the only threat to the galaxy is from a black hole in the centre of the milky way...and it's not hungry right now (in leymans terms). even if it was, we're 30,000 light years from it.
that's:
30 000 x (9.4607x10^12) = 2.83821x10^17..... or to write it in full: 2,838,210,000,000,000,000 km
in other words, we're safe..
the odd one
i was also asked how big the planets would need to be in order to form black holes in our solar system. this is, im sure, down to the fact i told him about the 'Schwarszchild radius'.
the schwarzschild radius is the maximum radius an object would need to be in order for a non-rotating, uncharged, black hole to form. any bigger than the radius and the object doesnt collaps into a black hole.... any smaller and the object becomes so dense that the escape velocity exceedes that of the speed of light... hence it becomes a black hole.
it can be calculated by this equation:
Rs=(2GM)/c^2
Rs is the schwarzschild radius
G is gravitational constant
M is mass of the object
c is the speed of light
so i worked them out :)
the sun- 2.949 km
mercury-0.487 mm
venus-7.21 mm
earth-8.86 mm
mars-0.952 mm
jupiter-2.815 m
saturn-84.3 cm
uranus-12.9 cm
neptune-15.2 cm
and there you go.
there are 3 other types of black holes that exist, but this is just one type. i cant be arsed to do all the workings out tonight
now i've done my maths, im off.
CIAO
