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Lucretius
2015-Nov-17, 02:14 AM
Is it physically possible to send a satellite, say something as small and simple as Sputnik, on a trajectory that parallels the solar system's polar axis?

Jens
2015-Nov-17, 02:32 AM
I'm not sure if I understand. Do you mean a trajectory that goes over the north pole and then the south pole, etc.? There are satellites in polar orbits, though I seem to recall that for some reason they are unstable.

Jeff Root
2015-Nov-17, 02:40 AM
If I understand what you mean, the Ulysses spacecraft did
something close to that in order to look at the Sun's poles.
A spacecraft in a perfectly polar orbit of the Sun would have
an inclination of 90 degrees to the ecliptic. I think Ulysses
had an inclination of about 80 degrees. To do that, it had
to go close to Jupiter to get flung out of the ecliptic plane
by Jupiter's gravity. The resulting orbit put the aphelion at
Jupiter's orbit and perihelion just outside Earth's orbit, with
an orbital period of about six years.

-- Jeff, in Minneapolis

Lucretius
2015-Nov-17, 02:55 AM
What I mean is a one way trip out of the solar system, like the Pioneers, but along the sun's polar axis.

Jeff Root
2015-Nov-17, 03:37 AM
It could be done with a somewhat larger rocket going closer
to Jupiter than Ulysses did. The rocket would thrust forward
along its trajectory at its closest point to Jupiter, and could
probably put the spacecraft onto a path 90 degrees from the
plane of the ecliptic.

-- Jeff, in Minneapolis

tony873004
2015-Nov-17, 06:23 AM
Sputnik orbited Earth. Yes, you can have polar Earth orbits as long as they are close to Earth. If the Moon were on a polar orbit, it would crash to the Earth in under a decade.

Polar orbits around the Sun can last indefinitely.

One-way out of the solar system? Absolutely. You can shoot a rocket in any direction you want. It would be well past the Sun before any subtle differences between ecliptic or polar played a roll.

Jens
2015-Nov-17, 01:06 PM
What I mean is a one way trip out of the solar system, like the Pioneers, but along the sun's polar axis.

As Jeff said, it's possible. The problem is, when a rocket leaves the earth you've already got a velocity of 100,000 km/h in the direction of the orbit and very little in the north-south direction. So somehow you have to lose that horizontal velocity and gain the vertical velocity. It will take a lot of energy, and you can get some from flybys but it might take a lot of effort.

John Mendenhall
2015-Nov-17, 03:30 PM
Good point, Jens. Ah, OP, why would we want to send a probe out along the solar axes? It sounds like a neat ides, but fundubg is scarce.

Regards, John M.

Lucretius
2015-Nov-18, 03:14 AM
To test a theory. Do you recall my recent thread, "A sink flow aether model of gravity"?

That was an ATM thread. I'm not sure what I can get away with here, but, to recapitulate, gravity was modeled as an energetic medium inflowing into matter, conferring upon matter its mass. Any gravitating body other than a perfectly spherical body, that is, a body that is oblate, such as Saturn, would have an other than spherically symmetric inflow pattern. The pattern would diverge at the polar axis, (both of them), and converge at the equatorial plane.

This would apply to any body that is disk shaped, including our solar system. Think of all those pictures you've seen of active galactic nuclei, with those incredible jets shooting out of both polar regions. This would be where the incoming velocity of the medium is lower, meaning there is less "gravity." A way "out."

The Pioneer anomaly has not been explained satisfactorily. If we sent a probe out of the solar system along the polar axis, my theory says that the probe would experience an anomalous "speeding up," meaning that gravity does not always and everywhere conform to perfect Newtonian concepts.

John Mendenhall
2015-Nov-18, 05:48 AM
I have the feeling you're not going to get funding for this mission.

Lucretius
2015-Nov-18, 04:43 PM
Of course not. If it were true it would upset the whole apple cart of physics and cosmology. Who wants that?

PetersCreek
2015-Nov-18, 06:20 PM
Lucretius,

If you're unsure of what you "can get away with here" then I suggest another reading of our rules. You may not advocate your ATM theories outside of the ATM forum nor may you argue against mainstream answers given in the Space/Astronomy Questions and Answers forum on an ATM basis.

DaveC426913
2015-Nov-19, 12:45 AM
The short answer is yes. With the right combination of maneuvers (both fuel- and slingshot-induced), it is quite possible to send a probe out of the system parallel to the sun's axis.



The Pioneer anomaly has not been explained satisfactorily.

Satisfactory to whom?
Last I checked, it has been fully accounted for by thermal recoil - no anomaly remains.

Lucretius
2015-Nov-19, 04:32 PM
The short answer is yes. With the right combination of maneuvers (both fuel- and slingshot-induced), it is quite possible to send a probe out of the system parallel to the sun's axis.


Could the Sun itself be used as a slingshot? Which combination of maneuvers would give the probe (yes, I muffed the title and the OP–probe, not satellite) the highest velocity?

antoniseb
2015-Nov-19, 05:05 PM
Could the Sun itself be used as a slingshot? Which combination of maneuvers would give the probe (yes, I muffed the title and the OP–probe, not satellite) the highest velocity?
No. Orbital mechanics allow some slingshot maneuvers using bodies that orbit larger bodies. If something were in a highly elliptical galactic orbit, a close pass of the Sun could change that orbit. A probe starting out at the Earth could not use the Sun to do a slingshot maneuver.

Jeff Root
2015-Nov-19, 06:49 PM
The Sun could be used, but to get close enough to the Sun
you'd probably have to go by Jupiter first. I think you'd
need a rocket with an enormous fuel supply (that keeps well)
because you'd first have to thrust at Jupiter to slow down
and fall toward the Sun, then thrust again while going past
the Sun to speed up as much as possible. Of course, doing
it without the gravity assists would require even more fuel.

-- Jeff, in Minneapolis

whybother2
2015-Nov-20, 04:30 AM
The Pioneer anomaly has not been explained satisfactorily. If we sent a probe out of the solar system along the polar axis, my theory says that the probe would experience an anomalous "speeding up," meaning that gravity does not always and everywhere conform to perfect Newtonian concepts.

I believe it is already well established that gravity does not always and everywhere conform to Newtonian concepts, but no matter.

I don't see this one getting off the ground either, but if we were to imagine that it were, then I see some issues. If I am understanding correctly, you have a theory of gravity that is different than the standard theory, and the difference would manifest itself in the direction of the "poles" of the solar system.

If this theory is wrong, then there is nothing to find.

If this theory is correct, then the extant theories of gravity are wrong, and the people who are telling you how to design the mission are using those extant theories. In particular, they will tell you that, to achieve your desired trajectory, you need to send the spacecraft near one of the "poles" of a large planet. So, if you don't believe their theory, should you believe what they tell you about how to target your spacecraft?

Unless the differences between your theory and the extant theories were to be very small. In that case, the errors introduced by the people who are designing mission trajectories for you will also be very small, and perhaps negligible. But then, very accurate measurement of the progress of your spacecraft would be required to evaluate your theory, as would very accurate modelling of the predictions of the two theories (yours, and the extant theory). If you need help designed the trajectory of your spacecraft, are you going to need help evaluating the data that come in?

It seems to me that being sufficiently proficient to design a mission trajectory would be a good idea - if you can't do that, how are you going to evaluate the data when it comes in? It would also allow you to do things like predict the motion of earth-orbitting satellites, some of which are in polar orbits, and determine whether your theory could be tested just as well (or perhaps even more easily) by analysis of the motion of existing satellites, without any new mission at all. I am not familiar with your theory, so I can't tell how large any anomalies in the motion of earth-orbitting satellites or sun-escaping hyperbolic satellites would be.

tusenfem
2015-Nov-20, 07:46 AM
I don't see this one getting off the ground either, but if we were to imagine that it were, then I see some issues. If I am understanding correctly, you have a theory of gravity that is different than the standard theory, and the difference would manifest itself in the direction of the "poles" of the solar system.



Okay and that's where it stops, there is NO DISCUSSION OF ATM IDEAS IN Q&A.
Thread closed for the moment.