Question about propulsion
Was wondering yesterday, solar sails, light pushing a spacecraft.
Then started thinking:
old car headlight with reflector . light beam, should have a reaction force too?
light exhaust speed is C
Should also work for heat, as heat is also IR radiation
So nuclear core heated close to critical with reflector screen should work too!
Space is very cold, cools reflector, like Webb telescope screen.
So the math?
Interstellar space travel close to C made easy?
Then I vaguely remembered Pioneer needed a correction because of the radiation from the RTGs..
https://en.wikipedia.org/wiki/Pioneer_anomaly
So what are we waiting for to go to the stars?
On Wednesday, 24 August 2022 at 07:21:45 UTC+1, Jan Panteltje wrote:
Question about propulsionfrom the RTGs..
Was wondering yesterday, solar sails, light pushing a spacecraft.
Then started thinking:
old car headlight with reflector . light beam, should have a reaction force >too?
light exhaust speed is C
Should also work for heat, as heat is also IR radiation
So nuclear core heated close to critical with reflector screen should work >too!
Space is very cold, cools reflector, like Webb telescope screen.
So the math?
Interstellar space travel close to C made easy?
Then I vaguely remembered Pioneer needed a correction because of the radiation
https://en.wikipedia.org/wiki/Pioneer_anomaly
So what are we waiting for to go to the stars?
Sounds reasonable. Although after spending all that time slowly accelerating >you
would have to turn the light source around at half way point just as you
were
getting up speed. And start decelerating again. Might take ages to get
there.
Plus all the interstellar dust gas etc would so badly damage the craft and >occupants
all that would arrive at the destination would be a badly damaged
spaceship
and some rather dead passengers.
I like the Oumuamua method. Find a handy local nickel iron asteroid. Terraform >it
to a long tubular shape 1/2 mile long maybe. Hollow out the inside for small >city
sized accomadation that would be safe from meteorites and radiation.
Put a nuclear reactor powered dynamo at the mid point and use that to
supply the thrust to spin the cigar shaped craft on a mid point axis to >supply artificial gravity on either side of the mid point of the spaceship. >And set it off spinning towards the nearest star with some sort of initial >propulsion
blast. Once it=E2=80=99s at a hi speed it could slingshot from star
to star
just like an interstellar Oumuamua spaceship.
Have a whole network of these hi speed craft going around the galaxy like
a
hi speed train network. Drop off and drop on would have to be done
locally on each star by space shuttle like crafts which would blast
off from any habitable local planets to catch up to these passing hi speed >interstellar
crafts.
Might get from our sun to the nearest star in maybe only a couple of hundred >thousand
years! Who knows that might be enough time for the passengers to evolve into >a
new species!!
I have some power laser, still considering
hanging it from some wires and pulsing the light to see if I can get it to swing.
Will let you know if it works.
On Tuesday, 6 September 2022 at 09:34:04 UTC+1, Jan Panteltje wrote:
On a sunny day (Sat, 03 Sep 2022 17:25:15 GMT) it happened Jan PanteltjeHow about attaching the laser to something to keep it from moving,
<pN> wrote in <tf02me>:
I have some power laser, still consideringSo, did a first simple test
hanging it from some wires and pulsing the light to see if I can get it to swing.
Will let you know if it works.
http://panteltje.com/pub/laser_propulsion_test_1_IXIMG_0856.JPG
this laser is 1 W input, will burn (and did in the cardboard box) a hole in a piece of cardboard.
It looks like when I wait until it is 100 % steady hanging and then pulse the current
it does get a push, but could just as well be effect the earth magnetic field on the wires.
point it downwards and , if you have one, project the beam onto one
of those digital electronic precision laboratory weigh scales?
On a sunny day (Sat, 03 Sep 2022 17:25:15 GMT) it happened Jan PanteltjeHow about attaching the laser to something to keep it from moving,
<pN> wrote in <tf02me>:
I have some power laser, still consideringSo, did a first simple test http://panteltje.com/pub/laser_propulsion_test_1_IXIMG_0856.JPG
hanging it from some wires and pulsing the light to see if I can get it to swing.
Will let you know if it works.
this laser is 1 W input, will burn (and did in the cardboard box) a hole in a piece of cardboard.
It looks like when I wait until it is 100 % steady hanging and then pulse the current
it does get a push, but could just as well be effect the earth magnetic field on the wires.
Thing is heavy, better get a free hanging diode only, and some more power. Batteries empty from testing now... recharging.
Nice laser, from ebay, had it for years
Always wear protective glasses,
Never look into laser with remaining eye.
On a sunny day (Sat, 10 Sep 2022 01:32:10 -0700 (PDT)) it happened Lou
<uk> wrote in
...@googlegroups.com>:
On Tuesday, 6 September 2022 at 09:34:04 UTC+1, Jan Panteltje wrote:Very good, I considered that.
On a sunny day (Sat, 03 Sep 2022 17:25:15 GMT) it happened Jan Panteltje >> <pN> wrote in <tf02me>:How about attaching the laser to something to keep it from moving,
I have some power laser, still consideringSo, did a first simple test
hanging it from some wires and pulsing the light to see if I can get it to swing.
Will let you know if it works.
http://panteltje.com/pub/laser_propulsion_test_1_IXIMG_0856.JPG
this laser is 1 W input, will burn (and did in the cardboard box) a hole in a piece of cardboard.
It looks like when I wait until it is 100 % steady hanging and then pulse the current
it does get a push, but could just as well be effect the earth magnetic field on the wires.
point it downwards and , if you have one, project the beam onto one
of those digital electronic precision laboratory weigh scales?
In high school physics we had a tube with a rotating vane in it that you could get to rotate by shining a light on it:
https://en.wikipedia.org/wiki/Crookes_radiometer
read the text, its easy to mistake heat radiation in such a case for light pressure.
So I wanted to really measure any 'reaction force'.
Will be playing with it some more, maybe get a more powerful laser diode from ebay, but shipping takes a long time these days
If so, will post about it here.
Thank you for the feedback!
(Ha! I never agreed with Maxwells component in his
model of emr anyways.
For me light, and electricity, is just an oscillating or changing magnetic field.
The
electric electron bit is fantasy. Proof is you can just rotate a magnet
and generate
both electricity...and emr waves.)
However to get back to my point the reference says if it were light pressure >rather
than heat radiation the vanes move in the opposite direction. That is
in
Crookes radiometer the vanes rotate towards the light source whereas
light pressure predicts they should rotate away from the source.
So if you do have electronic precision scales and tried measuring the force >then I assume you could distinguish which effect is at play.
That is: If it's light pressure the scale would record extra weight.
Or:
If it's heat radiation...the scale should measure a weight loss,
assuming
the same effects from Crookes radiometer are at play.
PS
I found this site http://umdberg.pbworks.com/w/page/50455623/Momentum%20of%20a%20laser%20beamThis sounds reasonable. But why are you doing this? Isn’t it already
and it gives 3.4 pico Newtons for a 1 mW laser pointer
My 1W laser will thus generate 1000 times as much, or 3.4 micro Newtons.
Bit afraid of using higher power lasers...
But let's say a focused 1000 W light bulb would generate 3.4 milli Newtons...
?
On Saturday, 17 September 2022 at 14:33:34 UTC+1, Jan Panteltje wrote:
PS
Imagine then your pool/electron analogy. The pool is the vacuum, the waves in >the
water the light waves. The atoms are a row of buckets at the edge of the pool >that only fill
if the water level rises above the level of the pool surface. Which they do >when each wave
hits the row of buckets. The buckets auto empty into an external pipe when each
bucket is
full.
You thus have a mechanical system, replicating right down to the atomic
level what happens when wave light hits the detector and transmits energy to >the
circuit.
I found this siteand it gives 3.4 pico Newtons for a 1 mW laser pointer
http://umdberg.pbworks.com/w/page/50455623/Momentum%20of%20a%20laser%20beam >>
My 1W laser will thus generate 1000 times as much, or 3.4 micro Newtons.Bit afraid of using higher power lasers...
But let's say a focused 1000 W light bulb would generate 3.4 milli Newtons...?
This sounds reasonable. But why are you doing this? Isn=E2=80=99t it already >an
accepted fact that a laser can supply the push for a spacecraft
in lieu of the solar sail?
Here=E2=80=99s a quote from the wiki Solar Sail page:
=E2=80=9CA useful analogy to solar sailing may be a sailing boat; the light >exerting a force on the mirrors is akin to a sail being blown by the wind. >High-energy laser beams could be used as an alternative light source to exert >much greater force than would be possible using sunlight, a concept known
as beam sailing.=E2=80=9D
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