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r4pt0r

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Yea I'm just saying it IS possible to put a probe into the Plutonian ( that was cool to type ) orbit. But yes it'd take a big rocket and big money.

Because here's the thing. I do this all the time in RSS. Take the FASA SaturnV, retrofit the SIVB with hypergolic engines and fuel. And that's it. The probe core IS the probe. The only payload is the power source. So you have this ejection stage with massive DV numbers I can take anywhere.

What about the science?

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76 AU is a lot harder to manage than 32 AU. And even at 32, we're only getting a few hours of flyby. But who knows what the next 10-15 years will bring as far as technology and understanding. And we may have the technology to make a Sedna mission feasible within the next 20 years or so, but Sedna may not be as an attractive target by then.

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Engineering wise almost anything is possible. If you factor in probe durability (since not flying by takes considerably more time), financial cost and political support, things become very complicated. The fact that you have a mission reaping rewards half a century later (meaning more than a career later) will greatly reduce people's preparedness to engage such a project. I am not even talking about the chances of things breaking permanently during that period. Reducing the time span quickly adds cost.

No you shoot the probe out on the same trajectory as NH. Just with a REALLY large ejectionn stage that stays with it for ten years.

@Nibb31 - Badum Ts.

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No you shoot the probe out on the same trajectory as NH. Just with a REALLY large ejectionn stage that stays with it for ten years.

@Nibb31 - Badum Ts.

The problem is building an ejection stage with 10km/s of Delta-V that will reliably reignite after ten years, and is lightweight enough to actually be put onto a 10 year transfer orbit.

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Here is the 2013 NASA planetary science division decadal survey, where a bunch of scientists get together and decide what NASA's priorities should be in this area for the next decade. I recommend anyone rooting for a Sedna probe to read through it to see how much interest they have in one, or to just Ctrl+f 'Sedna' if they're impatient.
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Yea I'm just saying it IS possible to put a probe into the Plutonian ( that was cool to type ) orbit. But yes it'd take a big rocket and big money.

Because here's the thing. I do this all the time in RSS. Take the FASA SaturnV, retrofit the SIVB with hypergolic engines and fuel. And that's it. The probe core IS the probe. The only payload is the power source. So you have this ejection stage with massive DV numbers I can take anywhere.

it is possible if you want to wait 100 years such that the apoapsis is so close to pluto the dV required to match speed is low enough. Put a whole bunch of stages around Diemos at 70% of SOI, then join the stages together us a minimal amount of thrust and mostly gravity turns, ION burn approaching pluto and correct orbit with close approach retro burn to maximum stable elliptical orbit, the ION drive burns off of carry on power supply. {it works in KSP}

Im suprised this thread has not migrated to manned missions and warp drives, yet.

So why would you only want to put the probe core, and if it was only the probe core how would you know you achieved orbit?

Is there some reason of value to go to orbit Pluto or go to Sedna? Any possible reward for the investment, the energy density of post plutonium orbit compared to earth/mars transition is almost zero, every ounce of power you would need you would have to take with you. There is no power to land or sample, you could blast a probe into the planet, but you would need a huge IR power supply and receiver to characterize the ejecta.

Before we talk about fancy mission to the outer planetoids, lets talk about ways to improve power generation efficiency per mass of long-lived spacecraft.

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Also, is Pluto really that bright? Or is the contrast exaggerated to make the surface features more visible?

Rather than contrast, I guess it looks so bright because of the exposure time, but I could be wildly wrong.

Strangely enough, NASA has published these photos in a press release but hasn't uploaded them to the LORRI "raw" image depository yet

And here's a cropped version so you don't have to zoom in. I knew Charon was very big compared to the Earth-Moon system, but damn, that's big big. (don't worry, they actually aren't so close to each other)

zoom.png

- - - Updated - - -

Five days to closest approach...!

And less than two days only to our last ever look at the opposite hemisphere!

- - - Updated - - -

Doesn't Pluto resemble a vintage-Mars?

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Are those actual sizes and distances?

I guess distance is a bit shaky anyway, since perspective can be tricky.

Also, is Pluto really that bright? Or is the contrast exaggerated to make the surface features more visible?

Brightness is not an intrinsic property, it depends on exposure time and camera technology. Even the human eye does not see the same thing every time and from person to person.

Though it should be noted that the sun is actually visibly present that far away. It weakens to about 1/1500th of Earth's brightness, but that is actually quite a bit brighter than you would intuitively expect. According to Phil Plait, that is actually about 150 to 450 times (depending on its position in orbit) as bright as full Moon as seen from Earth. A good full Moon casts shadows, allows you to read a book without other light and is easily captured on film/sensor. Something 250 times brighter means a moderately decent amount of light being about.

As it turns out, the Sun is a rather big lump of radiation :D

Such a wholesome coloration, and the surface is starting to get crisp! Charon is like a dull kid who eats glue next to Pluto's splendor :P

It is pretty neat they are so different, especially since sources seem to indicate the current concensus is that Charon and Pluto came from the same collision event. I wonder whether that theory will need revisiting.

Edited by Camacha
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Are those true colors (or at least a calculated "true colors" image from sensor data)?

This brown color is weird. I expected more grey. And more black.

Judging from what we saw from Hubble, some colour was to be expected.

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It is pretty neat they are so different, especially since sources seem to indicate the current concensus is that Charon and Pluto came from the same collision event. I wonder whether that theory will need revisiting.

That big "crater" we saw a few weeks ago (which will sadly be on the other side of Pluto during the encounter) also complicates things. :huh:

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Only two specific wavelength (something red and blue ?), the other (green ! yellow ! purple !) is interpreted from visual wavelengths (mind, wavelengths) minus the available filters. Probably that's why it's pretty red IMHO.

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Only two specific wavelength (something red and blue ?), the other (green ! yellow ! purple !) is interpreted from visual wavelengths (mind, wavelengths) minus the available filters. Probably that's why it's pretty red IMHO.

In the latest New Horizons Reddit AMA I asked: "How are you able to create true color images despite the lack of a green filter onboard New Horizons? Thanks."

New Horizons postdoc Amanda Zangari replied: "Pluto’s spectrum is pretty boring in the visible, we can interpolate what the green should be, especially if we know what kind of ice we’re looking at. The blue and red channels include the green information which helps. The IR is harder to extrapolate, and actually tells us stuff about what Pluto is made up off (in conjunction with the methane), which is why we got that instead."

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Still, that's not a good enough reason not to include just one more filter. It's not like it would gonna complicate the mission.

But this will have to do. So far it looks spectacular. I can't believe we're actually seeing this after so many decades. What makes me even more joyfull is the fact I've always imagined it looking like this.

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Still, that's not a good enough reason not to include just one more filter. It's not like it would gonna complicate the mission.

The quote above your posts seems to strongly suggest they had to make a choice between the two. Even without the quote it would probably be safe to assume NASA deliberated long and hard what to include and what to leave at home.

Have you written that letter yet? I would love to hear what NASA has to say :)

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The quote above your posts seems to strongly suggest they had to make a choice between the two.

Yes, they did have to make a choice. Not exactly sure why, but probably room constraints on the chip. It's a pushbroom sensor like HiRISE, not a filter wheel.

---- not related ----

Interesting. Aside from the SOFIA airborne telescope's recent Pluto occultation, it turns out a few other robotic eyes around the solar system will be pointed towards Pluto: on encounter day, Cassini; starting July 23rd and for a week, Spitzer; starting in October, for nearly 3 months and every 30 seconds, Kepler K2.

http://solarsystem.nasa.gov/news/display.cfm?News_ID=49449

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