[Music throughout] Scientists used supercomputer simulations
to throw eight different types of stars at a monster black hole.
Their goal is to create more realistic models of
tidal disruption events, which occur when unlucky stars stray
too close to black holes. Gravitational forces create intense
tides that deform the stars and break them into streams of gas.
These simulations are the first to combine the
physical effects of Einstein’s general theory of relativity and
virtual stars with realistic internal structures.
This schematic shows the stars’ trajectory. In this
version of the simulations, the black hole has 1 million times the Sun’s mass
and the stars are about 24 million miles away at their
closest. The model stars range from about
one-tenth to 10 times the Sun’s mass. The colors reflect
their densities, from the lowest, shown in blue, to the highest,
in yellow.
In some cases,
the stars are fully pulled apart. In others,
they’re only partially disrupted. As these
stars move farther from the black hole, their own gravity pulls them
back together. Surprisingly, the stars that fully
and partially disrupt aren’t cleanly divided by mass.
The Sun-like star, along with those with 0.15,
0.3, and 0.7 solar masses, survive
their close encounters. But stars with 0.4,
0.5, 3, and 10 times the Sun’s mass are
completely torn apart. The difference between
survival and destruction depends on the star’s internal density.
Simulations like these
will help astronomers build a better picture of these catastrophic events
occurring in galaxies millions of light-years away.
[NASA]