Reading through other parts of Nyrath's site, I saw discussions of how a drive
plume can be detected from here to Antares, but I didn't notice anything about
how far away you can detect a ship which is using an Handwavium drive, which
(as everyone knows) has no rocket exhaust. Let's say you move by generating a
small black hole in front of you and a negative mass equivalent (generates a
push rather than a pull) behind you. a) how would this be detected? b) how far
away could you reasonably expect to detect a ship, just by its temperature?
> On 2 Dec 2004 at 8:36, laserlight@quixnet.net wrote:
> Reading through other parts of Nyrath's site, I saw discussions of how
Depends how good your Handwavium detector is. ;-)
> Let's say you move by generating a small black hole in front
As you're generating two equal but opposite artificial gravity sources they
will from a large distance cancel each other out and be undetectable.
At a closer distance then they will distort the local gravitational field and
will hence be detectable. The distance at which the become detectable will
depend on the distance between them (and hence on the size of the ship) and
the resolution of your gravity detector.
> Steve Pugh wrote:
Only along certain lines, where the waves cross in exact opposite patterns.
Off those lines, you'll pick up some sort of disturbance (but whether or not
you'll *recognize* it from all the background
clutter is another story ;-) If I could do ASCII art wave inter-
ference patterns to illustrate this, I'd do so. But I can't, so...
Mk
***
Reading through other parts of Nyrath's site, I saw discussions of how a drive
plume can be detected from here to Antares, but I didn't notice anything about
how far away you can detect a ship which is using an Handwavium drive, which
(as everyone knows) has no rocket exhaust.
***
Just as an aside, remember that Antares is 520 ly away; you may have the
resolution to see the plume, but have to wait half a millenium to see.
PSB? I always assumed FTL sensors had somewhat less clarity.
The_Beast
> Doug Evans wrote:
I'm going to have to find some time and go read the discussion stuff. We can
barely detect Jovian planets out 150 ly; how big are these plumes supposed to
be??
Mk
> Reading through other parts of Nyrath's site, I saw discussions of how
That was figurative....although it may be that you can detect the shuttle main
drive out to Rigel Kent. Or was it just to Pluto? Go wander around the site
where Nyrath has his 3 way chart, you'll find it.
laserlight@quixnet.net said:
> Reading through other parts of Nyrath's site, I saw discussions of how
There would be hawking radiation from the black hole for a start. Depending on
your definition of small, the black hole may evaporate long before it can be
used to go very far.
Both would probably generate gravity waves. The black hole would bend the
light of anything it occulted. Any mass falling into the blackhole (e.g. dust)
will heat up and generate X rays.
What's holding the negative mass together btw? It's definitely not gravity.
It's probably going to be quite big so you're going to need a lot of energy to
hold it together, which itself could be detected. If you can't compress it to
be really small, then it's a big object which is probably highly visible to
both visible light and radar.
I thought that it is the generally accepted theory that nothing, including
light in all is forms, could escape the grasp of the black hole if it was past
the event horizion (though I haven't kept up on most of the new theories). It
would seem that any matter being "eaten" by the black hole, would not have any
detectable radiation, except that on the "normal" side of the event horizion.
Anyway, sensors, such as rader, tend not to detect the object itself, but
rather detect the influence of the object on its surroundings, hence radar
creates an "artificial" environment by the progagation of radar waves, then
measures any returns from any object they encounter. the operator can
generally tell what kind of object the sensor found by comparing the new data
with data of established objects. A black hole is an anomely that is detected
by the lack of data beyond a certain point.
Using wave propagation theory, there is point to when the relected energy does
not produce a signficant return or a return above ambient
levels. I have assumed that in FT and FT/FB, that all the ships use
some form of radar, hence the lack of detailed information beyond a certain
point. It would make things very interesting when you have a 40 mass destroyer
and a 40 mass light cruiser. Using sensor blind rules for FT (ie blobs for
ships not in the active detection range) would make the game even more
insteresting.
> Samuel Penn <sam@bifrost.demon.co.uk> wrote:
laserlight@quixnet.net said:
> Reading through other parts of Nyrath's site, I saw discussions of how
There would be hawking radiation from the black hole for a start. Depending on
your definition of small, the black hole may evaporate long before it can be
used to go very far.
Both would probably generate gravity waves. The black hole would bend the
light of anything it occulted. Any mass falling into the blackhole (e.g. dust)
will heat up and generate X rays.
What's holding the negative mass together btw? It's definitely not gravity.
It's probably going to be quite big so you're going to need a lot of energy to
hold it together, which itself could be detected. If you can't compress it to
be really small, then it's a big object which is probably highly visible to
both visible light and radar.
> On Friday 03 December 2004 18:09, Thomas Westbrook wrote:
side
> of the event horizion.
Look up Hawking radiation. Basically, black holes evaporate given enough time.
A *lot* of time is needed, but micro black holes formed at the time of the big
bang have had long enough to evaporate by now. No idea how big a 'micro' black
hole is however.
Matter falling into a black hole also gives off a lot of detectable radiation
before it hits the event horizon. A black hole (I'm guessing here) may collect
a ring of hot dust around it as well.
> On 3 Dec 2004 at 19:44, Samuel Penn wrote:
The shortish version is that space continually creates particle/anti-
particle pairs via quantum fluctuations. Normally these pairs anihilate each
other in a very short period of time. Energy is conserved as the energy
liberated when the anihilated equals the energy used to create them.
However, at the very edge of the event horizon one half of the pair may get
pulled into the black hole whilst the other half escapes. Hence the black hole
will seemingly emit the escaping halves.
In order to conserve mass, energy, momentum, and most importantly the entropy
of ths system the black hole must effectively lose mass in order to compensate
for this effect.
Look, Hawkings came up with this, I did a degree in physics and I just about
understand the very simple version....
> Basically, black holes evaporate given
One of the key points is that smaller black holes lose mass via this method
faster than big black holes. So if you're a small black hole you get stuck in
a vicious circle and end up going 'poof'.
> Indy wrote:
What's the wavelength of the gravity waves?
;-)
> On Friday 03 December 2004 21:17, Steve Pugh wrote:
[...stuff on black holes...]
> Look, Hawkings came up with this, I did a degree in physics and I
Didn't he also recently loose a bet that information was destroyed by black
holes? Now it's thought that information that goes into a black hole is
preserved.
I never did a degree in physics.
> > Basically, black holes evaporate given
Having now had a chance to look up micro black holes, their mass is put at
less than 10^14 kg (black holes as big as this last longer than the current
age of the universe, but would be about the size of an electron). A cubic
kilometer of water is 10^12kg (which, I think, would accelerate you at 0.06g
if it was 100m distant and squashed into a black hole as part of our mythical
space drive). For any decent acceleration, I don't think evaporation is going
to be an issue, however I don't think it's going to be very black.
The bending of light rays at the edges of the micro black hole would be the
easiest as the asmith of the angle of refraction is a coefecient of a fixed
number verses range.
"laserlight@quixnet.net" <laserlight@quixnet.net> wrote:Reading through other
parts of Nyrath's site, I saw discussions of how a drive plume can be detected
from here to Antares, but I didn't notice anything about how far away you can
detect a ship which is using an Handwavium drive, which (as everyone knows)
has no rocket exhaust. Let's say you move by generating a small black hole in
front of you and a negative mass equivalent (generates a push rather than a
pull) behind you. a) how would this be detected? b) how far away could you
reasonably expect to detect a ship, just by its temperature?
> laserlight@quixnet.net wrote:
I cannot answer [a], but the answer to [b] is on my site
at http://www.projectrho.com/rocket/rocket3w.html
Assuming the ship is running silent (i.e., not using a fusion exhaust with an
energy of 2.5 terawatts) the minimum detection range will depend upon the
enemy seeing the ship due to the infrared heat of its hull.
No, you cannot defeat this by refrigerating the hull, see the website for
detail.
The equation is:
Rd = 13.4 * sqrt(A) * T^2 where: Rd = maximum range the infrared signature can
be detected with current technology (presumably Full Thrust technology will be
better) in kilometers sqrt(x) = square root of x A = spacecraft's projected
area in square meters. If the ship is a convex shape, the projected area will
be about one quarter of its surface area. T = surface temperature in Kelvins,
room temperature
is about 285-290 k, water freezes at 273 k.
Lessee....
A Russian Oscar submarine is 154 meters long and has a beam of 18 meters. If
it was a spaceship, and was