After Pluto... Options

[Guest_exobioquest_*]

After pluto and any other KBO its set to intercept, how far can NH go before it dies on use? Can it reach the heliopause? Does it have any means of analyzing the heliopause and interstellar wind beyond it?

[nprev]

Just to add another question, have any candidate KBOs been identified for NH yet?

[alan]

I wouldn't expect them to pick a KBO target right away. There are a couple of new survey telescopes under development which will significantly increase the options while New Horizons in on the way to Pluto. This one for example PAN-STARRS, projected to begin in 2009, is expected to find 20,000 KBO's.

[edstrick]

They said on a press breifing today that they'd start the active search for KB objects about 2012. Post Pluto-encounter, the delta-V capability with the expected onboard fuel is a 1/10 degree wide cone expanding from the point of pluto-intercept. It's not worth the effort to search now for KB objects that will be in that narrow cone after 2015, when things like the Synoptic Survey Telescope will be deep-scanning the sky for KB objects by the hundreds of thousands and more.

[nprev]

They said on a press breifing today that they'd start the active search for KB objects about 2012.  Post Pluto-encounter, the delta-V capability with the expected onboard fuel is a 1/10 degree wide cone expanding from the point of pluto-intercept.  It's not worth the effort to search now for KB objects that will be in that narrow cone after 2015, when things like the Synoptic Survey Telescope will be deep-scanning the sky for KB objects by the hundreds of thousands and more.

I see; thanks, Ed and Alan.

Makes sense; Pluto doesn't have enough mass to alter the spacecraft's course to any significant degree (ta-da, da!)

[abalone]

They said on a press breifing today that they'd start the active search for KB objects about 2012.  Post Pluto-encounter, the delta-V capability with the expected onboard fuel is a 1/10 degree wide cone expanding from the point of pluto-intercept.  It's not worth the effort to search now for KB objects that will be in that narrow cone after 2015, when things like the Synoptic Survey Telescope will be deep-scanning the sky for KB objects by the hundreds of thousands and more.

I think it is a bit more than that. Delta V of say 100-150m/s when travelling at 13km/s equates to a cone of more like 1 deg rather than 1/10 deg

[edstrick]

"....Pluto doesn't have enough mass to alter the spacecraft's course to any significant degree ...."

Even if it did.... the trajectory past Pluto is almost 100% "constrained". Primary mission science goals REQUIRE radio occultation by BOTH Pluto and Charon. There is essentially one trajectory that can give that result, with the main variation being which 6 1/2 <is that right> orbit of Chiron around Pluto puts it into the right position for the second occultation.

[abalone]

Quick calculation. Max Delta V anticipated is about 210 m/s, this post Pluto-encounter wide cone expanding from the point of pluto-intercept of almost exactly 2.0 deg. Compare this to the moon as visble from Earth being about 1/2 deg.

That makes a cone 4X that apparaent diameter of the moon. The reason they are not searching yet is twofold.

1. they dont know where that cone will be until after launch
2. just as importantly, even after launch and the cone can be determined, where do you search for an object that will be in this cone in 9 years time. That of course depends on its orbit. The longer you leave the search, the smaller the area that needs to be searched

[Holder of the Tw...]

They said on a press breifing today that they'd start the active search for KB objects about 2012.  Post Pluto-encounter, the delta-V capability with the expected onboard fuel is a 1/10 degree wide cone expanding from the point of pluto-intercept.  It's not worth the effort to search now for KB objects that will be in that narrow cone after 2015, when things like the Synoptic Survey Telescope will be deep-scanning the sky for KB objects by the hundreds of thousands and more.

When they do start that search, Pluto (and any KBO targets) will be smack in the middle of the milky way in Sagitarius. This is an area normally avoided by planetoid hunters in the past, because of the dense star field. I wonder how they're going to address this issue? You need very good resolution, on the order of nearly perfect seeing from the ground, to pull anything out of the background.

[ToSeek]

When they do start that search, Pluto (and any KBO targets) will be smack in the middle of the milky way in Sagitarius. 

Just because Pluto is there, does that mean that any KBO NH can fly by must also be there? I would think that with a years-long cruise ahead of it, there's a wide swath where a possible KBO could be, if it's at the right distance.

[ljk4-1]

Just because Pluto is there, does that mean that any KBO NH can fly by must also be there? I would think that with a years-long cruise ahead of it, there's a wide swath where a possible KBO could be, if it's at the right distance.

Here's some real heresy: Why flyby Pluto when more interesting KBOs will likely be discovered between now and 2015? Can NH be retargeted for them? How about some of the interesting ones we know now, including the one that is bigger than Pluto (I will NOT say its unofficial name)? I think we should use Jupiter to whip NH out of the ecliptic to it.

[abalone]

years-long cruise ahead of it, there's a wide swath where a possible KBO could be, if it's at the right distance.

Yes that is true but the wide swath where a possible KBO could is all will be smack in the middle of the milky way in Sagitarius. It is not until about 2011 that the target field has moved into a more favorable location

[Holder of the Tw...]

Just because Pluto is there, does that mean that any KBO NH can fly by must also be there? I would think that with a years-long cruise ahead of it, there's a wide swath where a possible KBO could be, if it's at the right distance.

New Horizons will not have many years to live after Pluto, so the KBO's have to be fairly close. They didn't get as much plutonium as they wanted for the RTGs, and there was some question early on as to whether the spacecraft would be at full power even at Pluto. Even if the rendezvous point with the KBO clears the milky way, the object is not stationary in the sky and will have moved there from a point that was in a fairly dense sky background (unless it's in some very weird retrograd orbit). You need to have located it by the time NH reaches Pluto in order for a course change to have maximum effect.

[ljk4-1]

New Horizons will not have many years to live after Pluto, so the KBO's have to be fairly close.  They didn't get as much plutonium as they wanted for the RTGs, and there was some question early on as to whether the spacecraft would be at full power even at Pluto.  Even if the rendezvous point with the KBO clears the milky way, the object is not stationary in the sky and will have moved there from a point that was in a fairly dense sky background (unless it's in some very weird retrograd orbit).  You need to have located it by the time NH reaches Pluto in order for a course change to have maximum effect.

Any other gas giant planets conveniently along the way where NH could get an extra boost?

[mchan]

Any other gas giant planets conveniently along the way where NH could get an extra boost?

After Jupiter, there are no gas giants to help further on the way to Pluto. Beyond Pluto, there are no known gas giants. It would be fantastic if a gas giant were to found beyond Pluto and that would be in the narrow cone of possble post-Pluto trajectories.