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Let's look at a transfer orbit, it's orbital velocity at apoapsis, escape velocity and exhaust velocity.

For an ellipse with periapsis and apoapsis $r_{peri}, r_{apo}$

$$a = \frac{r_{peri} + r_{apo}}{2}$$

$$ v_{apo} = \sqrt{G M_E \left( \frac{2}{r_{apo}} - \frac{1}{a} \right)} $$

$$ v_{circ} = \sqrt{ \frac{G M_E}{a}} $$

$$ v_{esc} = \sqrt{2}v_{circ} = \sqrt{ \frac{2 G M_E}{a}} $$

and the critical exchaust velocity is that which shooting out the back of a spacecraft at apoapsis, moving at $v_{apo}$ would still have escape velocity:

$$v_{ex, crit} = v_{apo} + v_{esc}$$

Plotting those, you can see that for the second impulse at apoapsis, for exhaust velocities of 2000, 3000 and 4000 m/s, (roughly Isp's of 200, 300 and 400), the exhaust would have escape velocity for apoapsese of roughly 80,000 130,00 and 260,000 kilometers.

There are certainly spacecraft put in Earth orbit out that far, but they are rare.

• What is the highest non-equatorial earth orbit used?
• What artificial satellite has the farthest orbit around the Earth?

For most satellites put in orbit closer to Earth, the exhaust does not reach escape velocity. Instead, the exhaust orbits the Earth and will slowly mix its momentum with other atoms of the atmosphere and begin to thermalize and mix physically with the atmosphere.

It's a whole 'nuther ball of wax for electric propulsion! Back at the "turn of the century" (i.e. 2001) satellites to GEO were all (or nearly all) sent with conventional chemical propulsion. These days all-electric GEO telecommunications satellites are all the rage because it saves so much weight. In addition to using electric propulsion for station keeping which was developed earlier using arcjets, now ion propulsion is common both for station-keeping and going from LEO to GEO by spiraling outwards.

You can estimate the exhaust velocity of an ion engine using

$$\frac{v}{c} = \sqrt{\frac{2E}{m_0 c^2}}. $$

Choose $E=$ 100 keV and $m_0 c^2=$ 931 MeV times 50 to 200 AMU and you get between 0.2 and 0.1% of the speed of light, which is way beyond escape velocity. You can safely assume that any angular momentum gained by electric propulsion in Earth orbit at or beyond reasonable LEO is compensated by an equal and opposite angular momentum of ions flying out of the back of the spacecraft directly into either the interplanetary magnetic field, or completely outside of the solar system.

A 20 meb (milli-envelope-back) calculation shows the Earth's magnetic field is way to small and weak to contain these in cyclotron orbits.

So I've just asked Where do ion propulsion's ions go? Do they remain in the solar system or shoot out into interstellar space?

Python script for math and plots: https://pastebin.com/47wBu6sJ

Let's look at a transfer orbit, it's orbital velocity at apoapsis, escape velocity and exhaust velocity.

For an ellipse with periapsis and apoapsis $r_{peri}, r_{apo}$

$$a = \frac{r_{peri} + r_{apo}}{2}$$

$$ v_{apo} = \sqrt{G M_E \left( \frac{2}{r_{apo}} - \frac{1}{a} \right)} $$

$$ v_{circ} = \sqrt{ \frac{G M_E}{a}} $$

$$ v_{esc} = \sqrt{2}v_{circ} = \sqrt{ \frac{2 G M_E}{a}} $$

and the critical exchaust velocity is that which shooting out the back of a spacecraft at apoapsis, moving at $v_{apo}$ would still have escape velocity:

$$v_{ex, crit} = v_{apo} + v_{esc}$$

Plotting those, you can see that for the second impulse at apoapsis, for exhaust velocities of 2000, 3000 and 4000 m/s, (roughly Isp's of 200, 300 and 400), the exhaust would have escape velocity for apoapsese of roughly 80,000 130,00 and 260,000 kilometers.

There are certainly spacecraft put in Earth orbit out that far, but they are rare.

• What is the highest non-equatorial earth orbit used?
• What artificial satellite has the farthest orbit around the Earth?

For most satellites put in orbit closer to Earth, the exhaust does not reach escape velocity. Instead, the exhaust orbits the Earth and will slowly mix its momentum with other atoms of the atmosphere and begin to thermalize and mix physically with the atmosphere.

It's a whole 'nuther ball of wax for electric propulsion! Back at the "turn of the century" (i.e. 2001) satellites to GEO were all (or nearly all) sent with conventional chemical propulsion. These days all-electric GEO telecommunications satellites are all the rage because it saves so much weight. In addition to using electric propulsion for station keeping which was developed earlier using arcjets, now ion propulsion is common both for station-keeping and going from LEO to GEO by spiraling outwards.

You can estimate the exhaust velocity of an ion engine using

$$\frac{v}{c} = \sqrt{\frac{2E}{m_0 c^2}}. $$

Choose $E=$ 100 keV and $m_0 c^2=$ 931 MeV times 50 to 200 AMU and you get between 0.2 and 0.1% of the speed of light, which is way beyond escape velocity. You can safely assume that any angular momentum gained by electric propulsion in Earth orbit at or beyond reasonable LEO is compensated by an equal and opposite angular momentum of ions flying out of the back of the spacecraft. Depending on the scenario they could become trapped by the Earth's magnetic field and spiral into Earth's poles, thereby assuring that the angular momentum is transferred to the Earth's solid body, or if far enough away, leak out into the solar system after bending in the Earths' magnetic field, making it more complicated.

So I've just asked Where do ion propulsion's ions go? Do they remain in the solar system or shoot out into interstellar space?

Python script for math and plots: https://pastebin.com/47wBu6sJ

Let's look at a transfer orbit, it's orbital velocity at apoapsis, escape velocity and exhaust velocity.

For an ellipse with periapsis and apoapsis $r_{peri}, r_{apo}$

$$a = \frac{r_{peri} + r_{apo}}{2}$$

$$ v_{apo} = \sqrt{G M_E \left( \frac{2}{r_{apo}} - \frac{1}{a} \right)} $$

$$ v_{circ} = \sqrt{ \frac{G M_E}{a}} $$

$$ v_{esc} = \sqrt{2}v_{circ} = \sqrt{ \frac{2 G M_E}{a}} $$

and the critical exchaust velocity is that which shooting out the back of a spacecraft at apoapsis, moving at $v_{apo}$ would still have escape velocity:

$$v_{ex, crit} = v_{apo} + v_{esc}$$

Plotting those, you can see that for the second impulse at apoapsis, for exhaust velocities of 2000, 3000 and 4000 m/s, (roughly Isp's of 200, 300 and 400), the exhaust would have escape velocity for apoapsese of roughly 80,000 130,00 and 260,000 kilometers.

There are certainly spacecraft put in Earth orbit out that far, but they are rare.

• What is the highest non-equatorial earth orbit used?
• What artificial satellite has the farthest orbit around the Earth?

For most satellites put in orbit closer to Earth, the exhaust does not reach escape velocity. Instead, the exhaust orbits the Earth and will slowly mix its momentum with other atoms of the atmosphere and begin to thermalize and mix physically with the atmosphere.

It's a whole 'nuther ball of wax for electric propulsion! Back at the "turn of the century" (i.e. 2001) satellites to GEO were all (or nearly all) sent with conventional chemical propulsion. These days all-electric GEO telecommunications satellites are all the rage because it saves so much weight. In addition to using electric propulsion for station keeping which was developed earlier using arcjets, now ion propulsion is common both for station-keeping and going from LEO to GEO by spiraling outwards.

You can estimate the exhaust velocity of an ion engine using

$$\frac{v}{c} = \sqrt{\frac{2E}{m_0 c^2}}. $$

Choose $E=$ 100 keV and $m_0 c^2=$ 931 MeV times 50 to 200 AMU and you get between 0.2 and 0.1% of the speed of light, which is way beyond escape velocity. You can safely assume that any angular momentum gained by electric propulsion in Earth orbit at or beyond reasonable LEO is compensated by an equal and opposite angular momentum of ions flying out of the back of the spacecraft directly into either the interplanetary magnetic field, or completely outside of the solar system.

A 20 meb (milli-envelope-back) calculation shows the Earth's magnetic field is way to small and weak to contain these in cyclotron orbits.

So I've just asked Where do ion propulsion's ions go? Do they remain in the solar system or shoot out into interstellar space?

Let's look at a transfer orbit, it's orbital velocity at apoapsis, escape velocity and exhaust velocity.

For an ellipse with periapsis and apoapsis $r_{peri}, r_{apo}$

$$a = \frac{r_{peri} + r_{apo}}{2}$$

$$ v_{apo} = \sqrt{G M_E \left( \frac{2}{r_{apo}} - \frac{1}{a} \right)} $$

$$ v_{circ} = \sqrt{ \frac{G M_E}{a}} $$

$$ v_{esc} = \sqrt{2}v_{circ} = \sqrt{ \frac{2 G M_E}{a}} $$

and the critical exchaust velocity is that which shooting out the back of a spacecraft at apoapsis, moving at $v_{apo}$ would still have escape velocity:

$$v_{ex, crit} = v_{apo} + v_{esc}$$

Plotting those, you can see that for the second impulse at apoapsis, for exhaust velocities of 2000, 3000 and 4000 m/s, (roughly Isp's of 200, 300 and 400), the exhaust would have escape velocity for apoapsese of roughly 80,000 130,00 and 260,000 kilometers.

There are certainly spacecraft put in Earth orbit out that far, but they are rare.

• What is the highest non-equatorial earth orbit used?
• What artificial satellite has the farthest orbit around the Earth?

For most satellites put in orbit closer to Earth, the exhaust does not reach escape velocity. Instead, the exhaust orbits the Earth and will slowly mix its momentum with other atoms of the atmosphere and begin to thermalize and mix physically with the atmosphere.

It's a whole 'nuther ball of wax for electric propulsion! Back at the "turn of the century" (i.e. 2001) satellites to GEO were all (or nearly all) sent with conventional chemical propulsion. These days all-electric GEO telecommunications satellites are all the rage because it saves so much weight. In addition to using electric propulsion for station keeping which was developed earlier using arcjets, now ion propulsion is common both for station-keeping and going from LEO to GEO by spiraling outwards.

You can estimate the exhaust velocity of an ion engine using

$$\frac{v}{c} = \sqrt{\frac{2E}{m_0 c^2}}. $$

Choose $E=$ 100 keV and $m_0 c^2=$ 931 MeV times 50 to 200 AMU and you get between 0.2 and 0.1% of the speed of light, which is way beyond escape velocity. You can safely assume that any angular momentum gained by electric propulsion in Earth orbit at or beyond reasonable LEO is compensated by an equal and opposite angular momentum of ions flying out of the back of the spacecraft directly into either the interplanetary magnetic field, or completely outside of the solar system.

A 20 meb (milli-envelope-back) calculation shows the Earth's magnetic field is way to small and weak to contain these in cyclotron orbits.

So I've just asked Where do ion propulsion's ions go? Do they remain in the solar system or shoot out into interstellar space?

Python script for math and plots: https://pastebin.com/47wBu6sJ

Let's look at a transfer orbit, it's orbital velocity at apoapsis, escape velocity and exhaust velocity.

For an ellipse with periapsis and apoapsis $r_{peri}, r_{apo}$

$$a = \frac{r_{peri} + r_{apo}}{2}$$

$$ v_{apo} = \sqrt{G M_E \left( \frac{2}{r_{apo}} - \frac{1}{a} \right)} $$

$$ v_{circ} = \sqrt{ \frac{G M_E}{a}} $$

$$ v_{esc} = \sqrt{2}v_{circ} = \sqrt{ \frac{2 G M_E}{a}} $$

and the critical exchaust velocity is that which shooting out the back of a spacecraft at apoapsis, moving at $v_{apo}$ would still have escape velocity:

$$v_{ex, crit} = v_{apo} + v_{esc}$$

Plotting those, you can see that for the second impulse at apoapsis, for exhaust velocities of 2000, 3000 and 4000 m/s, (roughly Isp's of 200, 300 and 400), the exhaust would have escape velocity for apoapsese of roughly 80,000 130,00 and 260,000 kilometers.

There are certainly spacecraft put in Earth orbit out that far, but they are rare.

• What is the highest non-equatorial earth orbit used?
• What artificial satellite has the farthest orbit around the Earth?

For most satellites put in orbit closer to Earth, the exhaust does not reach escape velocity. Instead, the exhaust orbits the Earth and will slowly mix its momentum with other atoms of the atmosphere and begin to thermalize and mix physically with the atmosphere.

It's a whole 'nuther ball of wax for electric propulsion! Back at the "turn of the century" (i.e. 2001) satellites to GEO were all (or nearly all) sent with conventional chemical propulsion. These days all-electric GEO telecommunications satellites are all the rage because it saves so much weight. In addition to using electric propulsion for station keeping which was developed earlier using arcjets, now ion propulsion is common both for station-keeping and going from LEO to GEO by spiraling outwards.

You can estimate the exhaust velocity of an ion engine using

$$\frac{v}{c} = \sqrt{\frac{2E}{m_0 c^2}}. $$

Choose $E=$ 100 keV and $m_0 c^2=$ 931 MeV times 50 to 200 AMU and you get between 0.2 and 0.1% of the speed of light, which is way beyond escape velocity. You can safely assume that any angular momentum gained by electric propulsion in Earth orbit at or beyond reasonable LEO is compensated by an equal and opposite angular momentum of ions flying out of the back of the spacecraft directly into either the interplanetary magnetic field, or completely outside of the solar system. So I've just asked Where do ion propulsion's ions go? Do they remain in the solar system or shoot out into interstellar space?

Let's look at a transfer orbit, it's orbital velocity at apoapsis, escape velocity and exhaust velocity.

For an ellipse with periapsis and apoapsis $r_{peri}, r_{apo}$

$$a = \frac{r_{peri} + r_{apo}}{2}$$

$$ v_{apo} = \sqrt{G M_E \left( \frac{2}{r_{apo}} - \frac{1}{a} \right)} $$

$$ v_{circ} = \sqrt{ \frac{G M_E}{a}} $$

$$ v_{esc} = \sqrt{2}v_{circ} = \sqrt{ \frac{2 G M_E}{a}} $$

and the critical exchaust velocity is that which shooting out the back of a spacecraft at apoapsis, moving at $v_{apo}$ would still have escape velocity:

$$v_{ex, crit} = v_{apo} + v_{esc}$$

Plotting those, you can see that for the second impulse at apoapsis, for exhaust velocities of 2000, 3000 and 4000 m/s, (roughly Isp's of 200, 300 and 400), the exhaust would have escape velocity for apoapsese of roughly 80,000 130,00 and 260,000 kilometers.

There are certainly spacecraft put in Earth orbit out that far, but they are rare.

• What is the highest non-equatorial earth orbit used?
• What artificial satellite has the farthest orbit around the Earth?

For most satellites put in orbit closer to Earth, the exhaust does not reach escape velocity. Instead, the exhaust orbits the Earth and will slowly mix its momentum with other atoms of the atmosphere and begin to thermalize and mix physically with the atmosphere.

It's a whole 'nuther ball of wax for electric propulsion! Back at the "turn of the century" (i.e. 2001) satellites to GEO were all (or nearly all) sent with conventional chemical propulsion. These days all-electric GEO telecommunications satellites are all the rage because it saves so much weight. In addition to using electric propulsion for station keeping which was developed earlier using arcjets, now ion propulsion is common both for station-keeping and going from LEO to GEO by spiraling outwards.

You can estimate the exhaust velocity of an ion engine using

$$\frac{v}{c} = \sqrt{\frac{2E}{m_0 c^2}}. $$

Choose $E=$ 100 keV and $m_0 c^2=$ 931 MeV times 50 to 200 AMU and you get between 0.2 and 0.1% of the speed of light, which is way beyond escape velocity. You can safely assume that any angular momentum gained by electric propulsion in Earth orbit at or beyond reasonable LEO is compensated by an equal and opposite angular momentum of ions flying out of the back of the spacecraft directly into either the interplanetary magnetic field, or completely outside of the solar system.

A 20 meb (milli-envelope-back) calculation shows the Earth's magnetic field is way to small and weak to contain these in cyclotron orbits. 

So I've just asked Where do ion propulsion's ions go? Do they remain in the solar system or shoot out into interstellar space?