I bought a spaceship that can approach close to the speed of light, 
accelerating at a constant 1 g.
How long would it take to reach a star 10 light years away, assuming 
both Sol and the star are at rest relative to each other? And how long 
would it seem to take to the crew?


-- 

Regards
     Stephen

Post a reply to this message

Le 24/08/2015 12:15, Stephen a écrit :
> I bought a spaceship that can approach close to the speed of light,
> accelerating at a constant 1 g.
> How long would it take to reach a star 10 light years away, assuming
> both Sol and the star are at rest relative to each other? And how long
> would it seem to take to the crew?
>
>
What about the decelerating capability ? also 1 g ?

Post a reply to this message

On 8/24/2015 3:34 PM, Le_Forgeron wrote:
> Le 24/08/2015 12:15, Stephen a écrit :
>> I bought a spaceship that can approach close to the speed of light,
>> accelerating at a constant 1 g.
>> How long would it take to reach a star 10 light years away, assuming
>> both Sol and the star are at rest relative to each other? And how long
>> would it seem to take to the crew?
>>
>>
> What about the decelerating capability ? also 1 g ?
>
>

Yes, I am trying to make it simple. :-)


-- 

Regards
     Stephen

Post a reply to this message

Am 24.08.2015 um 12:15 schrieb Stephen:
> I bought a spaceship that can approach close to the speed of light,
> accelerating at a constant 1 g.
> How long would it take to reach a star 10 light years away, assuming
> both Sol and the star are at rest relative to each other? And how long
> would it seem to take to the crew?

Tell me when you plan to launch. I'd like to hitch a ride!


Speed of light is approximately 300,000 km/s = 3*10^8 m/s, or about
9.5*10^15 m/year; let's use a value of 1*10^16 m/year for simplicity. A
distance of 10 light years then equals 10*10^16 m = 1*10^17 m.

You'll have to turn around and decelerate after half the distance, which
is about 5*10^16 m.

An acceleration of 1g equals approximately 9.81 m/s^2; let's use a value
of 10 m/s^2 for simplicity.

The function of acceleration vs. time is constant for the first half of
the trip:

    a(t) = a

The function of speed vs. time is the integral of the acceleration
function; the integral of a constant function is the product of the
function's value and the parameter:

    v(t) = a t

The function of distance vs. time is the integral of the speed function,
which is a linear function of the form f(x)=cx; the integral of such a
function is F(x)=1/2 cx^2, i.e:

    d(t) = 1/2 a t^2

Let's compute the time at which we would reach the speed of light if
newtonian mechanics would apply:

    v(t)           = a        t
    3*10^8 m/s     = 10 m/s^2 t
    3*10^7         =  1  /s   t

which gives us

    t = 3*10^7 s = ca. 8300 hours = ca. 350 days = ca. 1 year.

Next, let's compute the distance traveled in this time under newtonian
laws of motion:

    d(t)          = 1/2    a         t^2
    d(3*10^7 s)   = 1/2 . 10 m/s^2 . (3*10^7 s)^2
                  =        5 m/s^2 .  9*10^14 s^2
                  =                  45*10^14 m

which gives us

    d = 4.5*10^15 m = ca. 1.5*10^7 light seconds = ca. 0.5 light years.

Finally, let's compute the time at which we would have completed the
half trip of 5*10^16 m, again if newtonian mechanics would apply:

    d(t)          = 1/2    a       t^2
    5*10^16 m     = 1/2 . 10 m/s^2 t^2
    5*10^16 m     =        5 m/s^2 t^2
    10^16         =        1  /s^2 t^2
    10^8          =        1  /s   t

which gives us

    t = 10^8 s = ca. 2.8*10^4 hours = ca. 1150 days = ca. 3.2 years.


Now what does this tell us about the situation with non-newtonian mechanics?

First, it gives us a rough idea about the trip's profile under
relativistic mechanics: As a first approximation, the first year will be
spent accelerating to light speed, and covering the first half light
year; the final half light year will be covered by a corresponding year
of decelerating from light speed back to zero; while the remaining 9
light years of the trip will be spent traveling close to the speed of
light, which will take a time of 9 years to the outside observer. The
total trip would thus take about 11 years.
Note that this is just a rough estimate, giving us nothing but a lower
bound: There's no way we can do it faster. Not at 1g acceleration.
However, we can also derive a rough upper bound in a similar manner:
Half the speed of light is still sufficiently relativistic within our
margin of error; we could obviously spend only the first half year
accelerating, bringing us up to half the speed of light and covering a
quarter of a light year; we could then cover the next 9.75 light years
drifting, which would take us 19.5 years; and finally a decelearation of
just half a year would bring us back to a speed of zero while covering
the final quarter of a light year. This profile would take 21 years in
total, both to us and to an outside observer. Obviously a full-burn,
turn, and full-burn profile would get us there faster.
We could therefore estimate the duration of the trip, as witnessed by an
outside observer, to be somewhere around 16 years; I will leave the
corresponding exact computations as an exercise to the reader.

Second, it gives us the /exact/ duration of the trip as experienced by
the traveler (as far as our generous application of rounding allows): He
will spend 3.2 years accelerating, then 3.2 years decelerating, for a
total of 6.4 years. About 13 years for a round trip.

Post a reply to this message

Am 24.08.2015 um 16:34 schrieb Le_Forgeron:
> Le 24/08/2015 12:15, Stephen a écrit :
>> I bought a spaceship that can approach close to the speed of light,
>> accelerating at a constant 1 g.
>> How long would it take to reach a star 10 light years away, assuming
>> both Sol and the star are at rest relative to each other? And how long
>> would it seem to take to the crew?
>>
>>
> What about the decelerating capability ? also 1 g ?

With that flight profile in mind, it seems reasonable to design the
spacecraft for a turn-around halfway down the road, to accelerate in the
opposite direction for the second half of the trip.

Post a reply to this message

Ah! ha!
You did not spot my deliberate mistake. <blush>

 >> accelerating at a constant 1 g.

Cannot be done. :-(
I forgot that as your speed increases your mass increases. So when you 
reach 0.9c your mass is 2.29 * your rest mass and the force needed to 
accelerate you increases as well.
0.99c > 7*m
0.999c > 22*m
0.9999c > 70 *m

http://hyperphysics.phy-astr.gsu.edu/hbase/relativ/tdil.html

But your approximations are good enough for me. So you passed the crew 
test.
Now I have to invent a reactionless drive using the vacuum energy.
Shouldn't take that long, I would think.


On 8/24/2015 4:32 PM, clipka wrote:
> Am 24.08.2015 um 12:15 schrieb Stephen:
>> I bought a spaceship that can approach close to the speed of light,
>> accelerating at a constant 1 g.
>> How long would it take to reach a star 10 light years away, assuming
>> both Sol and the star are at rest relative to each other? And how long
>> would it seem to take to the crew?
>
> Tell me when you plan to launch. I'd like to hitch a ride!
>
>
> Speed of light is approximately 300,000 km/s = 3*10^8 m/s, or about
> 9.5*10^15 m/year; let's use a value of 1*10^16 m/year for simplicity. A
> distance of 10 light years then equals 10*10^16 m = 1*10^17 m.
>
> You'll have to turn around and decelerate after half the distance, which
> is about 5*10^16 m.
>
> An acceleration of 1g equals approximately 9.81 m/s^2; let's use a value
> of 10 m/s^2 for simplicity.
>
> The function of acceleration vs. time is constant for the first half of
> the trip:
>
>      a(t) = a
>
> The function of speed vs. time is the integral of the acceleration
> function; the integral of a constant function is the product of the
> function's value and the parameter:
>
>      v(t) = a t
>
> The function of distance vs. time is the integral of the speed function,
> which is a linear function of the form f(x)=cx; the integral of such a
> function is F(x)=1/2 cx^2, i.e:
>
>      d(t) = 1/2 a t^2
>
> Let's compute the time at which we would reach the speed of light if
> newtonian mechanics would apply:
>
>      v(t)           = a        t
>      3*10^8 m/s     = 10 m/s^2 t
>      3*10^7         =  1  /s   t
>
> which gives us
>
>      t = 3*10^7 s = ca. 8300 hours = ca. 350 days = ca. 1 year.
>
> Next, let's compute the distance traveled in this time under newtonian
> laws of motion:
>
>      d(t)          = 1/2    a         t^2
>      d(3*10^7 s)   = 1/2 . 10 m/s^2 . (3*10^7 s)^2
>                    =        5 m/s^2 .  9*10^14 s^2
>                    =                  45*10^14 m
>
> which gives us
>
>      d = 4.5*10^15 m = ca. 1.5*10^7 light seconds = ca. 0.5 light years.
>
> Finally, let's compute the time at which we would have completed the
> half trip of 5*10^16 m, again if newtonian mechanics would apply:
>
>      d(t)          = 1/2    a       t^2
>      5*10^16 m     = 1/2 . 10 m/s^2 t^2
>      5*10^16 m     =        5 m/s^2 t^2
>      10^16         =        1  /s^2 t^2
>      10^8          =        1  /s   t
>
> which gives us
>
>      t = 10^8 s = ca. 2.8*10^4 hours = ca. 1150 days = ca. 3.2 years.
>
>
> Now what does this tell us about the situation with non-newtonian mechanics?
>
> First, it gives us a rough idea about the trip's profile under
> relativistic mechanics: As a first approximation, the first year will be
> spent accelerating to light speed, and covering the first half light
> year; the final half light year will be covered by a corresponding year
> of decelerating from light speed back to zero; while the remaining 9
> light years of the trip will be spent traveling close to the speed of
> light, which will take a time of 9 years to the outside observer. The
> total trip would thus take about 11 years.
> Note that this is just a rough estimate, giving us nothing but a lower
> bound: There's no way we can do it faster. Not at 1g acceleration.
> However, we can also derive a rough upper bound in a similar manner:
> Half the speed of light is still sufficiently relativistic within our
> margin of error; we could obviously spend only the first half year
> accelerating, bringing us up to half the speed of light and covering a
> quarter of a light year; we could then cover the next 9.75 light years
> drifting, which would take us 19.5 years; and finally a decelearation of
> just half a year would bring us back to a speed of zero while covering
> the final quarter of a light year. This profile would take 21 years in
> total, both to us and to an outside observer. Obviously a full-burn,
> turn, and full-burn profile would get us there faster.
> We could therefore estimate the duration of the trip, as witnessed by an
> outside observer, to be somewhere around 16 years; I will leave the
> corresponding exact computations as an exercise to the reader.
>
> Second, it gives us the /exact/ duration of the trip as experienced by
> the traveler (as far as our generous application of rounding allows): He
> will spend 3.2 years accelerating, then 3.2 years decelerating, for a
> total of 6.4 years. About 13 years for a round trip.
>


-- 

Regards
     Stephen

Post a reply to this message

On 8/24/2015 12:55 PM, Stephen wrote:
> Ah! ha!
> You did not spot my deliberate mistake. <blush>
>
>  >> accelerating at a constant 1 g.
>
> Cannot be done. :-(
> I forgot that as your speed increases your mass increases. So when you
> reach 0.9c your mass is 2.29 * your rest mass and the force needed to
> accelerate you increases as well.
> 0.99c > 7*m
> 0.999c > 22*m
> 0.9999c > 70 *m
>
> http://hyperphysics.phy-astr.gsu.edu/hbase/relativ/tdil.html
>
> But your approximations are good enough for me. So you passed the crew
> test.
> Now I have to invent a reactionless drive using the vacuum energy.
> Shouldn't take that long, I would think.
>
>
> On 8/24/2015 4:32 PM, clipka wrote:
>> Am 24.08.2015 um 12:15 schrieb Stephen:
>>> I bought a spaceship that can approach close to the speed of light,
>>> accelerating at a constant 1 g.
>>> How long would it take to reach a star 10 light years away, assuming
>>> both Sol and the star are at rest relative to each other? And how long
>>> would it seem to take to the crew?
>>
>> Tell me when you plan to launch. I'd like to hitch a ride!
>>
>>
>> Speed of light is approximately 300,000 km/s = 3*10^8 m/s, or about
>> 9.5*10^15 m/year; let's use a value of 1*10^16 m/year for simplicity. A
>> distance of 10 light years then equals 10*10^16 m = 1*10^17 m.
>>
>> You'll have to turn around and decelerate after half the distance, which
>> is about 5*10^16 m.
>>
>> An acceleration of 1g equals approximately 9.81 m/s^2; let's use a value
>> of 10 m/s^2 for simplicity.
>>
>> The function of acceleration vs. time is constant for the first half of
>> the trip:
>>
>>      a(t) = a
>>
>> The function of speed vs. time is the integral of the acceleration
>> function; the integral of a constant function is the product of the
>> function's value and the parameter:
>>
>>      v(t) = a t
>>
>> The function of distance vs. time is the integral of the speed function,
>> which is a linear function of the form f(x)=cx; the integral of such a
>> function is F(x)=1/2 cx^2, i.e:
>>
>>      d(t) = 1/2 a t^2
>>
>> Let's compute the time at which we would reach the speed of light if
>> newtonian mechanics would apply:
>>
>>      v(t)           = a        t
>>      3*10^8 m/s     = 10 m/s^2 t
>>      3*10^7         =  1  /s   t
>>
>> which gives us
>>
>>      t = 3*10^7 s = ca. 8300 hours = ca. 350 days = ca. 1 year.
>>
>> Next, let's compute the distance traveled in this time under newtonian
>> laws of motion:
>>
>>      d(t)          = 1/2    a         t^2
>>      d(3*10^7 s)   = 1/2 . 10 m/s^2 . (3*10^7 s)^2
>>                    =        5 m/s^2 .  9*10^14 s^2
>>                    =                  45*10^14 m
>>
>> which gives us
>>
>>      d = 4.5*10^15 m = ca. 1.5*10^7 light seconds = ca. 0.5 light years.
>>
>> Finally, let's compute the time at which we would have completed the
>> half trip of 5*10^16 m, again if newtonian mechanics would apply:
>>
>>      d(t)          = 1/2    a       t^2
>>      5*10^16 m     = 1/2 . 10 m/s^2 t^2
>>      5*10^16 m     =        5 m/s^2 t^2
>>      10^16         =        1  /s^2 t^2
>>      10^8          =        1  /s   t
>>
>> which gives us
>>
>>      t = 10^8 s = ca. 2.8*10^4 hours = ca. 1150 days = ca. 3.2 years.
>>
>>
>> Now what does this tell us about the situation with non-newtonian
>> mechanics?
>>
>> First, it gives us a rough idea about the trip's profile under
>> relativistic mechanics: As a first approximation, the first year will be
>> spent accelerating to light speed, and covering the first half light
>> year; the final half light year will be covered by a corresponding year
>> of decelerating from light speed back to zero; while the remaining 9
>> light years of the trip will be spent traveling close to the speed of
>> light, which will take a time of 9 years to the outside observer. The
>> total trip would thus take about 11 years.
>> Note that this is just a rough estimate, giving us nothing but a lower
>> bound: There's no way we can do it faster. Not at 1g acceleration.
>> However, we can also derive a rough upper bound in a similar manner:
>> Half the speed of light is still sufficiently relativistic within our
>> margin of error; we could obviously spend only the first half year
>> accelerating, bringing us up to half the speed of light and covering a
>> quarter of a light year; we could then cover the next 9.75 light years
>> drifting, which would take us 19.5 years; and finally a decelearation of
>> just half a year would bring us back to a speed of zero while covering
>> the final quarter of a light year. This profile would take 21 years in
>> total, both to us and to an outside observer. Obviously a full-burn,
>> turn, and full-burn profile would get us there faster.
>> We could therefore estimate the duration of the trip, as witnessed by an
>> outside observer, to be somewhere around 16 years; I will leave the
>> corresponding exact computations as an exercise to the reader.
>>
>> Second, it gives us the /exact/ duration of the trip as experienced by
>> the traveler (as far as our generous application of rounding allows): He
>> will spend 3.2 years accelerating, then 3.2 years decelerating, for a
>> total of 6.4 years. About 13 years for a round trip.
>>
>
>

Nerds.

Post a reply to this message

Am 24.08.2015 um 18:55 schrieb Stephen:
> Ah! ha!
> You did not spot my deliberate mistake. <blush>
> 
>>> accelerating at a constant 1 g.
> 
> Cannot be done. :-(
> I forgot that as your speed increases your mass increases. So when you
> reach 0.9c your mass is 2.29 * your rest mass and the force needed to
> accelerate you increases as well.
> 0.99c > 7*m
> 0.999c > 22*m
> 0.9999c > 70 *m

That certainly depends on whether you look at it from the perspective of
an outside observer (who will notice your acceleration decreasing, which
to him is actually the reason why you'll never seem to reach the speed
of light), or that of the traveler. To the latter, his mass remains
constant, and acceleration at a constant 1g is perfectly possible.

When taking on the perspective of the traveler, newtonian mechanics give
perfectly good answers, no matter what aspect you're looking at. (Unless
you're looking out the window.)

> http://hyperphysics.phy-astr.gsu.edu/hbase/relativ/tdil.html
> 
> But your approximations are good enough for me. So you passed the crew
> test.
> Now I have to invent a reactionless drive using the vacuum energy.
> Shouldn't take that long, I would think.

Nasa has already conducted first tests of such drives, with promising
results (to their own surprise). I kid you not.

https://en.wikipedia.org/wiki/Quantum_vacuum_thruster
https://en.wikipedia.org/wiki/RF_resonant_cavity_thruster

Post a reply to this message

Am 25.08.2015 um 08:08 schrieb clipka:

> That certainly depends on whether you look at it from the perspective of
> an outside observer (who will notice your acceleration decreasing, which
> to him is actually the reason why you'll never seem to reach the speed
> of light), or that of the traveler. To the latter, his mass remains
> constant, and acceleration at a constant 1g is perfectly possible.

This, BTW, follows directly from the most fundamental principle of
General Relativity: As long as you don't look out the window, you can't
tell whether you're accelerating, or are stationary in a gravitational
field excerting an equivalent force. In the latter case, your mass
obviously does not increase over time; therefore, neither does it in the
former case.

Post a reply to this message

Le 2015-08-25 03:09, clipka a écrit :
> Am 25.08.2015 um 08:08 schrieb clipka:
>
>  As long as you don't look out the window, you can't
> tell whether you're accelerating, or are stationary in a gravitational
> field excerting an equivalent force. In the latter case, your mass
> obviously does not increase over time; therefore, neither does it in the
> former case.
>

It depends on what you eat, and how much exercice you get.

;-)

-- 
/*Francois Labreque*/#local a=x+y;#local b=x+a;#local c=a+b;#macro P(F//
/*    flabreque    */L)polygon{5,F,F+z,L+z,L,F pigment{rgb 9}}#end union
/*        @        */{P(0,a)P(a,b)P(b,c)P(2*a,2*b)P(2*b,b+c)P(b+c,<2,3>)
/*   gmail.com     */}camera{orthographic location<6,1.25,-6>look_at a }

Post a reply to this message

Am 25.08.2015 um 15:27 schrieb Francois Labreque:
> Le 2015-08-25 03:09, clipka a écrit :
>> Am 25.08.2015 um 08:08 schrieb clipka:
>>
>>  As long as you don't look out the window, you can't
>> tell whether you're accelerating, or are stationary in a gravitational
>> field excerting an equivalent force. In the latter case, your mass
>> obviously does not increase over time; therefore, neither does it in the
>> former case.
>>
> 
> It depends on what you eat, and how much exercice you get.
> 
> ;-)

Dang. Too many nitpickers out here.

Post a reply to this message

Mike Horvath <mik### [at] gmailcom> wrote:

>
> Nerds.

Indeed! and you are not the only one who thinks so.
I updated Thunderbird yesterday and this thread has been deleted and ignored.
We must be getting too close to a truth that should not be discussed.

I knew that I should not have stopped off at Roswell a couple of years ago. A
marked man, I must be.

Post a reply to this message

clipka <ano### [at] anonymousorg> wrote:
> Am 24.08.2015 um 18:55 schrieb Stephen:
> > Ah! ha!
> > You did not spot my deliberate mistake. <blush>
> >
> >>> accelerating at a constant 1 g.
> >
> > Cannot be done. :-(
> > I forgot that as your speed increases your mass increases. So when you
> > reach 0.9c your mass is 2.29 * your rest mass and the force needed to
> > accelerate you increases as well.
> > 0.99c > 7*m
> > 0.999c > 22*m
> > 0.9999c > 70 *m
>
> That certainly depends on whether you look at it from the perspective of
> an outside observer (who will notice your acceleration decreasing, which
> to him is actually the reason why you'll never seem to reach the speed
> of light), or that of the traveler. To the latter, his mass remains
> constant, and acceleration at a constant 1g is perfectly possible.
>

Now introduce a third frame of reference.

Boggle! boggle! boggle.

> When taking on the perspective of the traveler, newtonian mechanics give
> perfectly good answers, no matter what aspect you're looking at. (Unless
> you're looking out the window.)
>

But that is the whole reason for having portholes.
To see the aberration of light.

> > http://hyperphysics.phy-astr.gsu.edu/hbase/relativ/tdil.html
> >
> > But your approximations are good enough for me. So you passed the crew
> > test.
> > Now I have to invent a reactionless drive using the vacuum energy.
> > Shouldn't take that long, I would think.
>
> Nasa has already conducted first tests of such drives, with promising
> results (to their own surprise). I kid you not.
>
> https://en.wikipedia.org/wiki/Quantum_vacuum_thruster
> https://en.wikipedia.org/wiki/RF_resonant_cavity_thruster


The BBC had a report on this earlier in the year. So I believe it.

Post a reply to this message

On 26-8-2015 17:51, Stephen wrote:
> Mike Horvath <mik### [at] gmailcom> wrote:
>
>>
>> Nerds.
>
> Indeed! and you are not the only one who thinks so.
> I updated Thunderbird yesterday and this thread has been deleted and ignored.
> We must be getting too close to a truth that should not be discussed.
>
> I knew that I should not have stopped off at Roswell a couple of years ago. A
> marked man, I must be.
>
>

Somehow, those things always happens to people developing means (or 
trying to) to travel to the stars...

-- 
Thomas

Post a reply to this message

On 26-8-2015 18:22, Stephen wrote:
> clipka <ano### [at] anonymousorg> wrote:

>> When taking on the perspective of the traveler, newtonian mechanics give
>> perfectly good answers, no matter what aspect you're looking at. (Unless
>> you're looking out the window.)
>>
>
> But that is the whole reason for having portholes.
> To see the aberration of light.
>

I seem to remember reading about simulations showing how stars would 
/creep/ towards the front of the vessel when speed approaches light 
speed. Turning blue of course. Nothing would be visible towards the 
sides or the back. Not like in Star Trek at all.

-- 
Thomas

Post a reply to this message

Thomas de Groot <tho### [at] degrootorg> wrote:
> On 26-8-2015 18:22, Stephen wrote:
> > clipka <ano### [at] anonymousorg> wrote:
>
> >> When taking on the perspective of the traveler, newtonian mechanics give
> >> perfectly good answers, no matter what aspect you're looking at. (Unless
> >> you're looking out the window.)
> >>
> >
> > But that is the whole reason for having portholes.
> > To see the aberration of light.
> >
>
> I seem to remember reading about simulations showing how stars would
> /creep/ towards the front of the vessel when speed approaches light
> speed. Turning blue of course. Nothing would be visible towards the
> sides or the back. Not like in Star Trek at all.
>

There was a relativistic patch for Ver 2.2

http://203.29.75.35/povray.unofficial.patches/thread/%3Cweb.3de6ef98c20e2bf3c571aa6c0%40news.povray.org%3E/?ttop=388410
&toff=300&mtop=199902

None of the links are still active. :-(

Post a reply to this message

On 27-8-2015 9:33, Stephen wrote:
> Thomas de Groot <tho### [at] degrootorg> wrote:
>> On 26-8-2015 18:22, Stephen wrote:
>>> clipka <ano### [at] anonymousorg> wrote:
>>
>>>> When taking on the perspective of the traveler, newtonian mechanics give
>>>> perfectly good answers, no matter what aspect you're looking at. (Unless
>>>> you're looking out the window.)
>>>>
>>>
>>> But that is the whole reason for having portholes.
>>> To see the aberration of light.
>>>
>>
>> I seem to remember reading about simulations showing how stars would
>> /creep/ towards the front of the vessel when speed approaches light
>> speed. Turning blue of course. Nothing would be visible towards the
>> sides or the back. Not like in Star Trek at all.
>>
>
> There was a relativistic patch for Ver 2.2
>
>
http://203.29.75.35/povray.unofficial.patches/thread/%3Cweb.3de6ef98c20e2bf3c571aa6c0%40news.povray.org%3E/?ttop=388410
> &toff=300&mtop=199902
>
> None of the links are still active. :-(
>
>

A little project for Christoph then, hmm?  ;-)

-- 
Thomas

Post a reply to this message

Le 2015-08-27 02:53, Thomas de Groot a écrit :
> On 26-8-2015 17:51, Stephen wrote:
>> Mike Horvath <mik### [at] gmailcom> wrote:
>>
>>>
>>> Nerds.
>>
>> Indeed! and you are not the only one who thinks so.
>> I updated Thunderbird yesterday and this thread has been deleted and
>> ignored.
>> We must be getting too close to a truth that should not be discussed.
>>
>> I knew that I should not have stopped off at Roswell a couple of years
>> ago. A
>> marked man, I must be.
>>
>>
>
> Somehow, those things always happens to people developing means (or
> trying to) to travel to the stars...
>
Trust no one.

-- 
/*Francois Labreque*/#local a=x+y;#local b=x+a;#local c=a+b;#macro P(F//
/*    flabreque    */L)polygon{5,F,F+z,L+z,L,F pigment{rgb 9}}#end union
/*        @        */{P(0,a)P(a,b)P(b,c)P(2*a,2*b)P(2*b,b+c)P(b+c,<2,3>)
/*   gmail.com     */}camera{orthographic location<6,1.25,-6>look_at a }

Post a reply to this message

On Thu, 27 Aug 2015 08:53:17 +0200, Thomas de Groot <tho### [at] degrootorg>  
wrote:

> On 26-8-2015 17:51, Stephen wrote:
>> Mike Horvath <mik### [at] gmailcom> wrote:
>>
>>>
>>> Nerds.
>>
>> Indeed! and you are not the only one who thinks so.
>> I updated Thunderbird yesterday and this thread has been deleted and  
>> ignored.
>> We must be getting too close to a truth that should not be discussed.
>>
>> I knew that I should not have stopped off at Roswell a couple of years  
>> ago. A
>> marked man, I must be.
>>
>>
>
> Somehow, those things always happens to people developing means (or  
> trying to) to travel to the stars...
>

https://www.reddit.com/r/UnresolvedMysteries/comments/1zsyz2/on_july_1954_a_man_arrives_at_tokyo_airport_in/

-- 
-Nekar Xenos-

Post a reply to this message

Stephen <mca### [at] aolcom> wrote:
> Cannot be done. :-(
> I forgot that as your speed increases your mass increases.

Your speed increases relative to what?

You are always at rest relative to yourself. Your mass doesn't increase
from your own perspective, no matter what something else measures your
speed to be. (From your own perspective it's that external observer's
mass that's increasing, not yours.)

-- 
                                                          - Warp

Post a reply to this message

Stephen <mca### [at] aolcom> wrote:
> How long would it take to reach a star 10 light years away, assuming 
> both Sol and the star are at rest relative to each other? And how long 
> would it seem to take to the crew?

Here's an easier question: How fast would you need to travel (from
the point of view of Earth) in order to reach that star in 10 years
from your own point of view?

-- 
                                                          - Warp

Post a reply to this message

Warp <war### [at] tagpovrayorg> wrote:
> Stephen <mca### [at] aolcom> wrote:
> > Cannot be done. :-(
> > I forgot that as your speed increases your mass increases.
>
> Your speed increases relative to what?
>
Your initial velocity. V0


> You are always at rest relative to yourself. Your mass doesn't increase
> from your own perspective, no matter what something else measures your
> speed to be. (From your own perspective it's that external observer's
> mass that's increasing, not yours.)
>

That is a valid way of looking at it.

You feel not the force of acceleration but the force of the rest of the
universe's mass increasing.


> --
>                                                           - Warp

Post a reply to this message

Thomas de Groot <tho### [at] degrootorg> wrote:
> On 26-8-2015 17:51, Stephen wrote:
> > Mike Horvath <mik### [at] gmailcom> wrote:
> >
> >>
> >> Nerds.
> >
> > Indeed! and you are not the only one who thinks so.
> > I updated Thunderbird yesterday and this thread has been deleted and ignored.
> > We must be getting too close to a truth that should not be discussed.
> >
> > I knew that I should not have stopped off at Roswell a couple of years ago. A
> > marked man, I must be.
> >
> >
>
> Somehow, those things always happens to people developing means (or
> trying to) to travel to the stars...
>

Which reminded me of a story by Harry Harrison* called Toy shop.
http://www.gutenberg.org/ebooks/22966

Because there was a story in the British press in the 70’s or 80’s that was very
similar. Some hobbyist in the depth of England, it could have been Norfolk or
the West Country. Invented a gizmo in his garden shed which did something
similar. Only he immigrated to Oz where someone sponsored him to research it.
Never heard about him again. Spooky!

*
I thought that it was an Isaac Asimov short story. But I came across it today
and it is only a couple of pages.

Post a reply to this message

Am 11.09.2015 um 22:06 schrieb Stephen:

> Which reminded me of a story by Harry Harrison* called Toy shop.
> http://www.gutenberg.org/ebooks/22966

Now /that's/ what I call true genius...

Post a reply to this message

On 9/11/2015 9:23 PM, clipka wrote:
> Am 11.09.2015 um 22:06 schrieb Stephen:
>
>> Which reminded me of a story by Harry Harrison* called Toy shop.
>> http://www.gutenberg.org/ebooks/22966
>
> Now /that's/ what I call true genius...
>

It has stuck with me for about 50 years.
I don't know whether it was my age or if there were a lot more "make you 
think" short stories. It was like a sub-sub-genre with points for 
brevity. You have probably read Knock. The shortest SF story. If not:
https://en.wikipedia.org/wiki/Knock_%28short_story%29




-- 

Regards
     Stephen

Post a reply to this message

On 12-9-2015 0:03, Stephen wrote:
> On 9/11/2015 9:23 PM, clipka wrote:
>> Am 11.09.2015 um 22:06 schrieb Stephen:
>>
>>> Which reminded me of a story by Harry Harrison* called Toy shop.
>>> http://www.gutenberg.org/ebooks/22966
>>
>> Now /that's/ what I call true genius...
>>
>
> It has stuck with me for about 50 years.
> I don't know whether it was my age or if there were a lot more "make you
> think" short stories. It was like a sub-sub-genre with points for
> brevity. You have probably read Knock. The shortest SF story. If not:
> https://en.wikipedia.org/wiki/Knock_%28short_story%29
>
>
>
>
Somehow, now that you mention it, this sub-sub-genre seems to have 
totally vanished from the shelves. A pity; it was most enjoyable.

Which reminds me of the following story by Damon Knight: "To Serve Man"
http://perrylocal.org/mostova/files/2011/09/To-Serve-Man.pdf
Like you, it stuck with me since the 1960's. I first read it in French 
translation, in the now legendary magazine /Planète/.

-- 
Thomas

Post a reply to this message

On 9/12/2015 8:31 AM, Thomas de Groot wrote:
> On 12-9-2015 0:03, Stephen wrote:
>> On 9/11/2015 9:23 PM, clipka wrote:
>>> Am 11.09.2015 um 22:06 schrieb Stephen:
>>>
>>>> Which reminded me of a story by Harry Harrison* called Toy shop.
>>>> http://www.gutenberg.org/ebooks/22966
>>>
>>> Now /that's/ what I call true genius...
>>>
>>
>> It has stuck with me for about 50 years.
>> I don't know whether it was my age or if there were a lot more "make you
>> think" short stories. It was like a sub-sub-genre with points for
>> brevity. You have probably read Knock. The shortest SF story. If not:
>> https://en.wikipedia.org/wiki/Knock_%28short_story%29
>>
>>
>>
>>
> Somehow, now that you mention it, this sub-sub-genre seems to have
> totally vanished from the shelves. A pity; it was most enjoyable.
>

Isaac Asimov had a weakness for Short-short stories that were puns.

> Which reminds me of the following story by Damon Knight: "To Serve Man"
> http://perrylocal.org/mostova/files/2011/09/To-Serve-Man.pdf
> Like you, it stuck with me since the 1960's. I first read it in French
> translation, in the now legendary magazine /Planète/.
>

That one is one of my memories too.
I did not read many magazines by the time the American ones got to 
Glasgow they would be in batches several months late. The British 
magazines would be difficult to find. It was mostly library books that 
kept me going.

-- 

Regards
     Stephen

Post a reply to this message

On 12-9-2015 10:50, Stephen wrote:
> On 9/12/2015 8:31 AM, Thomas de Groot wrote:
>> On 12-9-2015 0:03, Stephen wrote:
>>> On 9/11/2015 9:23 PM, clipka wrote:
>>>> Am 11.09.2015 um 22:06 schrieb Stephen:
>>>>
>>>>> Which reminded me of a story by Harry Harrison* called Toy shop.
>>>>> http://www.gutenberg.org/ebooks/22966
>>>>
>>>> Now /that's/ what I call true genius...
>>>>
>>>
>>> It has stuck with me for about 50 years.
>>> I don't know whether it was my age or if there were a lot more "make you
>>> think" short stories. It was like a sub-sub-genre with points for
>>> brevity. You have probably read Knock. The shortest SF story. If not:
>>> https://en.wikipedia.org/wiki/Knock_%28short_story%29
>>>
>>>
>>>
>>>
>> Somehow, now that you mention it, this sub-sub-genre seems to have
>> totally vanished from the shelves. A pity; it was most enjoyable.
>>
>
> Isaac Asimov had a weakness for Short-short stories that were puns.
>
>> Which reminds me of the following story by Damon Knight: "To Serve Man"
>> http://perrylocal.org/mostova/files/2011/09/To-Serve-Man.pdf
>> Like you, it stuck with me since the 1960's. I first read it in French
>> translation, in the now legendary magazine /Planète/.
>>
>
> That one is one of my memories too.
> I did not read many magazines by the time the American ones got to
> Glasgow they would be in batches several months late. The British
> magazines would be difficult to find. It was mostly library books that
> kept me going.
>
I really got started on SF when I moved to Amsterdam in '66 where I 
discovered Analog and began collecting SF books. Iirc Analog was the 
only magazine available in stores; others (no UK) were either not there 
or only irregularly.

-- 
Thomas

Post a reply to this message

On 9/12/2015 12:28 PM, Thomas de Groot wrote:
>> That one is one of my memories too.
>> I did not read many magazines by the time the American ones got to
>> Glasgow they would be in batches several months late. The British
>> magazines would be difficult to find. It was mostly library books that
>> kept me going.
>>
> I really got started on SF when I moved to Amsterdam in '66 where I
> discovered Analog and began collecting SF books. Iirc Analog was the
> only magazine available in stores; others (no UK) were either not there
> or only irregularly.

I was about ten when I found Kemlo the space cadet. I have been hooked 
ever since. Glasgow being a port, would get pallets of American Pulp 
Fiction that had been used as ballast. They were sold in "Second hand 
bookshops" where you could return them and get back half of what you 
paid. They were really subscription libraries for American genre 
fiction. Cowboy, WWII stories, Romantic and SF. These shops were always 
in poor parts of town, near either a railway station or the docks.

-- 

Regards
     Stephen

Post a reply to this message

On 12-9-2015 14:57, Stephen wrote:
> On 9/12/2015 12:28 PM, Thomas de Groot wrote:
>>> That one is one of my memories too.
>>> I did not read many magazines by the time the American ones got to
>>> Glasgow they would be in batches several months late. The British
>>> magazines would be difficult to find. It was mostly library books that
>>> kept me going.
>>>
>> I really got started on SF when I moved to Amsterdam in '66 where I
>> discovered Analog and began collecting SF books. Iirc Analog was the
>> only magazine available in stores; others (no UK) were either not there
>> or only irregularly.
>
> I was about ten when I found Kemlo the space cadet. I have been hooked
> ever since. Glasgow being a port, would get pallets of American Pulp
> Fiction that had been used as ballast. They were sold in "Second hand
> bookshops" where you could return them and get back half of what you
> paid. They were really subscription libraries for American genre
> fiction. Cowboy, WWII stories, Romantic and SF. These shops were always
> in poor parts of town, near either a railway station or the docks.
>

A treasure trove! No, I did not have that chance. For many years SF was 
restricted to Jules Verne, but I was hooked early on somehow, not in the 
least by the international space competition (Sputnik!). I still can 
remember putting my ear to the /wireless/ to listen to its 
bip-bip-bip..... :-)

-- 
Thomas

Post a reply to this message

On 9/13/2015 8:05 AM, Thomas de Groot wrote:
> A treasure trove!

No a house of ill repute. Where those poor, sad people came to get their 
fix of trash. That's how SF was thought of, at the time.

> No, I did not have that chance. For many years SF was
> restricted to Jules Verne, but I was hooked early on somehow, not in the
> least by the international space competition (Sputnik!). I still can
> remember putting my ear to the /wireless/ to listen to its
> bip-bip-bip..... :-)


That is on the far edge of my memory. :-)
The space race was exciting viewed from afar.

-- 

Regards
     Stephen

Post a reply to this message

On 13-9-2015 12:31, Stephen wrote:
> On 9/13/2015 8:05 AM, Thomas de Groot wrote:
>> A treasure trove!
>
> No a house of ill repute. Where those poor, sad people came to get their
> fix of trash. That's how SF was thought of, at the time.

That is true. My father was a fan of detective and horror stories but 
frowned upon SF while otoh he was genuinely interested in everything 
concerning space ;-)

It must be said that some of the vintage could be openly fascist 
sometimes. The Lensman and Skylark books for example. I think that those 
aspects contributed to my father's opinion.

>
>> No, I did not have that chance. For many years SF was
>> restricted to Jules Verne, but I was hooked early on somehow, not in the
>> least by the international space competition (Sputnik!). I still can
>> remember putting my ear to the /wireless/ to listen to its
>> bip-bip-bip..... :-)
>
>
> That is on the far edge of my memory. :-)
> The space race was exciting viewed from afar.
>

We have a small age difference, young man ;-)

-- 
Thomas

Post a reply to this message

On 9/14/2015 8:07 AM, Thomas de Groot wrote:
> On 13-9-2015 12:31, Stephen wrote:
>> On 9/13/2015 8:05 AM, Thomas de Groot wrote:
>>> A treasure trove!
>>
>> No a house of ill repute. Where those poor, sad people came to get their
>> fix of trash. That's how SF was thought of, at the time.
>
> That is true. My father was a fan of detective and horror stories but
> frowned upon SF while otoh he was genuinely interested in everything
> concerning space ;-)
>

The covers did not help them to be taken seriously. Generally a busty 
blond woman in a see through spacesuit being attacked by a BEM.

> It must be said that some of the vintage could be openly fascist
> sometimes. The Lensman and Skylark books for example. I think that those
> aspects contributed to my father's opinion.
>

True, very true. I have been trying to re-read some of my collection. 
Robert Heinlein is an author I cannot read any more. Sad. :-(
>>

>>
>>
>> That is on the far edge of my memory. :-)
>> The space race was exciting viewed from afar.
>>
>
> We have a small age difference, young man ;-)
>

Yes but I was only seven then. It makes a bigger difference at that age.

-- 

Regards
     Stephen

Post a reply to this message

On 14-9-2015 9:45, Stephen wrote:
> On 9/14/2015 8:07 AM, Thomas de Groot wrote:
>> On 13-9-2015 12:31, Stephen wrote:
>>> On 9/13/2015 8:05 AM, Thomas de Groot wrote:
>>>> A treasure trove!
>>>
>>> No a house of ill repute. Where those poor, sad people came to get their
>>> fix of trash. That's how SF was thought of, at the time.
>>
>> That is true. My father was a fan of detective and horror stories but
>> frowned upon SF while otoh he was genuinely interested in everything
>> concerning space ;-)
>>
>
> The covers did not help them to be taken seriously. Generally a busty
> blond woman in a see through spacesuit being attacked by a BEM.
>
>> It must be said that some of the vintage could be openly fascist
>> sometimes. The Lensman and Skylark books for example. I think that those
>> aspects contributed to my father's opinion.
>>
>
> True, very true. I have been trying to re-read some of my collection.
> Robert Heinlein is an author I cannot read any more. Sad. :-(

Yes indeed. He is a typical example. The man could write though. Ron 
Hubbard was one of those others, highly doubtful, authors although I 
don't think I ever read anything from him. He was already infamous 
enough for me to refuse to read him.

>>>
>
>>>
>>>
>>> That is on the far edge of my memory. :-)
>>> The space race was exciting viewed from afar.
>>>
>>
>> We have a small age difference, young man ;-)
>>
>
> Yes but I was only seven then. It makes a bigger difference at that age.
>

That is true. I was almost eleven at the time.

-- 
Thomas

Post a reply to this message

On 9/14/2015 12:50 PM, Thomas de Groot wrote:
> On 14-9-2015 9:45, Stephen wrote:

>>
>> True, very true. I have been trying to re-read some of my collection.
>> Robert Heinlein is an author I cannot read any more. Sad. :-(
>
> Yes indeed. He is a typical example. The man could write though.

True.

> Ron Hubbard was one of those others, highly doubtful, authors although I
> don't think I ever read anything from him. He was already infamous
> enough for me to refuse to read him.
>

Good old Elron. What can you say?



>>
>> Yes but I was only seven then. It makes a bigger difference at that age.
>>
>
> That is true. I was almost eleven at the time.
>

Almost sentient, then. :-)

-- 

Regards
     Stephen

Post a reply to this message

On 14-9-2015 14:20, Stephen wrote:
> On 9/14/2015 12:50 PM, Thomas de Groot wrote:
>> On 14-9-2015 9:45, Stephen wrote:
>
>>>
>>> True, very true. I have been trying to re-read some of my collection.
>>> Robert Heinlein is an author I cannot read any more. Sad. :-(
>>
>> Yes indeed. He is a typical example. The man could write though.
>
> True.
>
>> Ron Hubbard was one of those others, highly doubtful, authors although I
>> don't think I ever read anything from him. He was already infamous
>> enough for me to refuse to read him.
>>
>
> Good old Elron. What can you say?

Better keep a thoughtful/meaningful silence.

>
>
>
>>>
>>> Yes but I was only seven then. It makes a bigger difference at that age.
>>>
>>
>> That is true. I was almost eleven at the time.
>>
>
> Almost sentient, then. :-)
>

I sometimes wonder if I ever shall reach that stage ;-)

-- 
Thomas

Post a reply to this message

Thomas de Groot wrote:

> On 14-9-2015 14:20, Stephen wrote:
>> On 9/14/2015 12:50 PM, Thomas de Groot wrote:
>>> On 14-9-2015 9:45, Stephen wrote:
>>
>>>>
>>>> True, very true. I have been trying to re-read some of my collection.
>>>> Robert Heinlein is an author I cannot read any more. Sad. :-(
>>>
>>> Yes indeed. He is a typical example. The man could write though.
>>
>> True.
>>
>>> Ron Hubbard was one of those others, highly doubtful, authors although I
>>> don't think I ever read anything from him. He was already infamous
>>> enough for me to refuse to read him.
>>>
>>
>> Good old Elron. What can you say?
> 
> Better keep a thoughtful/meaningful silence.
> 
>>
>>
>>
>>>>
>>>> Yes but I was only seven then. It makes a bigger difference at that age.
>>>>
>>>
>>> That is true. I was almost eleven at the time.
>>>
>>
>> Almost sentient, then. :-)
>>
> 
> I sometimes wonder if I ever shall reach that stage ;-)
> 


Hmmm, I was 14 around then :)
-- 

Ger

Post a reply to this message

On 9/15/2015 8:06 AM, Ger wrote:
> Thomas de Groot wrote:
>
>> On 14-9-2015 14:20, Stephen wrote:

>>>
>>> Good old Elron. What can you say?
>>
>> Better keep a thoughtful/meaningful silence.
>>


No thought involved, I am happy to say. :-)

>>>
>>>
>>>
>>>>>
>>>>> Yes but I was only seven then. It makes a bigger difference at that age.
>>>>>
>>>>
>>>> That is true. I was almost eleven at the time.
>>>>
>>>
>>> Almost sentient, then. :-)
>>>
>>
>> I sometimes wonder if I ever shall reach that stage ;-)
>>

It's not all it's cracked up to be. ;-)

>
>
> Hmmm, I was 14 around then :)
>

A grown up, almost. :-)

-- 

Regards
     Stephen

Post a reply to this message

On 15-9-2015 10:11, Stephen wrote:
> On 9/15/2015 8:06 AM, Ger wrote:
>> Thomas de Groot wrote:
>>
>>> On 14-9-2015 14:20, Stephen wrote:
>
>>>>
>>>> Good old Elron. What can you say?
>>>
>>> Better keep a thoughtful/meaningful silence.
>>>
>
>
> No thought involved, I am happy to say. :-)
>
>>>>
>>>>
>>>>
>>>>>>
>>>>>> Yes but I was only seven then. It makes a bigger difference at
>>>>>> that age.
>>>>>>
>>>>>
>>>>> That is true. I was almost eleven at the time.
>>>>>
>>>>
>>>> Almost sentient, then. :-)
>>>>
>>>
>>> I sometimes wonder if I ever shall reach that stage ;-)
>>>
>
> It's not all it's cracked up to be. ;-)

So they say. So they say...

>
>>
>>
>> Hmmm, I was 14 around then :)
>>
>
> A grown up, almost. :-)
>

and it doesn't make us any younger :-)

-- 
Thomas

Post a reply to this message