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Old July 2nd 18, 09:14 PM posted to sci.astro.research
Richard D. Saam
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Default Spaceship Oumuamua

On 7/2/18 12:08 AM, jacobnavia wrote:
Le 01/07/2018 19:37, Richard D. Saam a écrit:
m/t = F/v = 1.39 x 10^8/41,000 = 3,400 g/sec or 3.4 kg/sec


OK, but this thing has been accelerating for months... Suppose just 4
months. At this ejection rate we have

material=3.4*3600*24*30*4
35 251 200.0 Kg

For an object whose mass is 2.82e8 Kg this represents
mass=2.82e8 Kg

mass/material

7.999727

i.e. this object should have lost 1/8th of its mass in 4 months...

And we should somehow see something of those 35 thousand tons of ejected
gas.

But maybe is not a spaceship, we will never know.

There is a recent paper
"A possible flyby anomaly for Juno at Jupiter"
https://arxiv.org/abs/1711.08893v2

a team of astronomers confirms the pioneer anomaly and other spacecraft
mysterious accelerations.

Maybe this object is experiencing the same "problem"?

That would be also a big scoop, maybe more productive than just an
interstellar cargo ship passing by.

:-)

jacob

My apologies, I made a mistake length m^3 cm^3 conversion
The ejection rate .034 kg/sec and not 3.4 kg/sec
*****************
Trying to get a dimensional feel of the problem:
Oumuamua's dimensions:
230 x 35 x 35 m = 282,000 m^3 or 2.82x10^9 cm^3
Assume 1 g/cc density
then mass = 2.82x10^9 g
Nature Letter says anomalous non gravity acceleration
at 4.92x10^-6 m/sec^2 or 4.92x10^-4 cm/sec^2
Therefore sun based radial Force
= 2.82x10^9 x 4.92x10^-4 = 1.39 x 10^6 dyne
Calculate ejected material by impulse momentum F = (m/t) x v
with hydrogen ejected at temperature 20 K
(perhaps there is a better temperature
sqrt(Boltzmann x 20K/hydrogen atomic weight) = 41,000 cm/sec
with hydrogen mass ejected on a second basis
m/t = F/v = 1.39 x 10^6/41,000 = 34 g/sec or .034 kg/sec
This net radial ejection mass quantity rate
does not seem to be that much
considering the low temperature gas potential of an object that has been
wandering in cold interstellar space for millions of years.

Richard D Saam