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## Main Question or Discussion Point

It is often said that passing the event horizon for a large black hole is basically a non event as the size of the tidal acceleration at the event horizon depends on the mass of the black hole.

But let's consider something else; what happens to the stars

We have the redshift formula for stars

[tex] \sqrt { \left| \left( 1-\sqrt {{\frac {r_{{s}}}{r}}} \right) \left(

1+\sqrt {{\frac {r_{{s}}}{r}}} \right) ^{-1} \right| }{\frac {1}{

\sqrt { \left| 1-{\frac {r_{{s}}}{r}} \right| }}}[/tex]

Which graphically looks like:

http://img442.imageshack.us/img442/4100/redshift.png [Broken]

But what do we measure about the stars

But let's consider something else; what happens to the stars

**in front**of a free falling observer falling radially at escape velocity into a black hole. Can we devise a formula that expresses the red or blue shift as seen by the observer?We have the redshift formula for stars

**behind us**, which is:[tex] \sqrt { \left| \left( 1-\sqrt {{\frac {r_{{s}}}{r}}} \right) \left(

1+\sqrt {{\frac {r_{{s}}}{r}}} \right) ^{-1} \right| }{\frac {1}{

\sqrt { \left| 1-{\frac {r_{{s}}}{r}} \right| }}}[/tex]

Which graphically looks like:

http://img442.imageshack.us/img442/4100/redshift.png [Broken]

But what do we measure about the stars

**ahead**of us?
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