[X] My Assistant

[hal_9000]

I can not find NH's trajectory on ssd.jpl.nasa.gov and others..
Can anyone post it here?
Thanks!!

[SpaceCat]

Ultimate Trajectory Question:

Will NH leave the solar system and continue outbound as Pioneer & Voyger have--- or eventually end up in a long 'comet-type' elipse around the sun?

[Greg Hullender]

Will NH leave the solar system and continue outbound as Pioneer & Voyger have--- or eventually end up in a long 'comet-type' elipse around the sun?

Using the current positon and velocity from the "where is NH" page:

http://pluto.jhuapl.edu/mission/whereis_nh.php

And the standard gravitational parameter for the Sun, from Wikipedia

http://en.wikipedia.org/wiki/Standard_grav...ional_parameter

We can figure the "hyperbolic excess" (the velocity at infinity) which I estimate at 12.7 kps.

Or, in other words, "that baby's never coming back!"

--Greg :-)

This page has some other interesting equations:

http://en.wikipedia.org/wiki/Hyperbolic_trajectory

[brellis]

Questions come to my feeble mind: how does the trajectory of the Sun around the Milky Way play into the escape velocities of spacecraft like the Voyagers, Pioneers and NH? At what point would it figure into the equation?

[dmuller]

Questions come to my feeble mind: how does the trajectory of the Sun around the Milky Way play into the escape velocities of spacecraft like the Voyagers, Pioneers and NH? At what point would it figure into the equation?

No. At launch, every spacecraft already has the orbital velocity of the Sun around the Milky Way center. Similar to leaving Earth orbit: the escape speed is the same regardless of which direction (towards [like Venus Express] or away [New Horizons] from the Sun) you launch your spacecraft out of the Earth parking orbit.

However, if you want to leave the Milky Way, then it comes into play as you'd launch a spacecraft in the direction of the Sun's movement to make full use of its orbital speed. Also, if you fly in the direction of the Sun's movement, then you'll reach the bow shock and other solar system border areas sooner (because they're closer to the Sun there).