>
> I just watched that Air Crash Investigators show about the Columbia
> disaster from a few nights ago.
> Why does the shuttle have to travel so fast to re-enter? Why can't it
> come in at a more normal speed and avoid the whole burning up thing?
> --
> Oz Lander.
> Straight and Level Down Under Forum.
> http://www.straightandleveldownunder.net

> I just watched that Air Crash Investigators show about the Columbia
> disaster from a few nights ago.
> Why does the shuttle have to travel so fast to re-enter? Why can't it
> come in at a more normal speed and avoid the whole burning up thing?
> --
> Oz Lander.

> "Oz Lander" there.com.ca> wrote in message
>
> news:fl2ovf$1d6$1@news-01.bur.connect.com.au...
>
>
>

>> I just watched that Air Crash Investigators show about the Columbia
>> disaster from a few nights ago.
>> Why does the shuttle have to travel so fast to re-enter? Why can't it
>> come in at a more normal speed and avoid the whole burning up thing?
>> --
>> Oz Lander.
>> Straight and Level Down Under Forum.
>>http://www.straightandleveldownunder.net

>
> ____________________________________________
>
>
> ...

> On Dec 28, 11:08 pm, "Oz Lander" there.com.ca> wrote:

>> I just watched that Air Crash Investigators show about the Columbia
>> disaster from a few nights ago.
>> Why does the shuttle have to travel so fast to re-enter? Why can't it
>> come in at a more normal speed and avoid the whole burning up thing?
>> --
>> Oz Lander.

>
> Oz, a spacecraft, satellite , moon , whatever to achieve orbit has to
> be moving at a hell of a speed. Think of the trajectory when you
> throw a ball horizontally. It gradually curves back down to earth.
> Now throw it a bit harder , and then harder and then harder again, see
> how the curve of the trajectory gets less. If you were above the
> atmosphere ( where there is still gravity but no air friction) its
> curvature will be the same as the earths, so it keeps being pulled
> down , but never gets there. For any object to move in a circle it
> requires a centripetal force towards the center of the circle.
> Gravity provides that force. Centripetal force required is equal to
> mv(squared)/ r where m is the mass, v is the velocity and r is the ...

>
>I just watched that Air Crash Investigators show about the Columbia
>disaster from a few nights ago.
>Why does the shuttle have to travel so fast to re-enter? Why can't it
>come in at a more normal speed and avoid the whole burning up thing?

> On Fri, 28 Dec 2007 12:08:15 +0000 (UTC), "Oz Lander"
>
> there.com.ca> wrote:
>

>>I just watched that Air Crash Investigators show about the Columbia
>>disaster from a few nights ago.
>>Why does the shuttle have to travel so fast to re-enter? Why can't it
>>come in at a more normal speed and avoid the whole burning up thing?

>
> G'Day OzLander,
>
> Terry's answer gives you the reasons why the shuttle has to reach a
> speed of about 27,000 kph in order to achieve orbital velocity. Note
> that this is the horizontal component of their velocity- the vertical
> launch at the beginning is to get them out of the atmosphere so that
> they can reach that speed.
> In order to return to earth you have to slow the machine down again,
> either by burning an equivalent amount of fuel (which you have to take
> with you when you launch, meaning even more fuel, etc. etc.) or by ...

> On Fri, 28 Dec 2007 12:08:15 +0000 (UTC), "Oz Lander"
>

> RT wrote:
>

>>
>> "Oz Lander" there.com.ca> wrote in message
>> news:fl2ovf$1d6$1@news-01.bur.connect.com.au...

>>>
>>> I just watched that Air Crash Investigators show about the Columbia
>>> disaster from a few nights ago.
>>> Why does the shuttle have to travel so fast to re-enter? Why can't
>>> it come in at a more normal speed and avoid the whole burning up
>>> thing? -- Oz Lander.
>>> Straight and Level Down Under Forum.
>>> http://www.straightandleveldownunder.net

>>
>> ____________________________________________
>>
>>
>> ...