Pluto flyover by New Horizons

[James Brown]

I very much doubt 1 inch story. First of all, such precision is not necessary and second, 1 inch with reference to what? surface of Pluto? but it's not defined that well. it has mountains and valleys mile(s) high/deep.

The more I think about it, barbos, the more I agree with you. I must have seriously misheard something, if what's quoted here is the same as what I heard on the (unfortunately deleted) documentary:

Nine and a half years and three billion miles later, NASA's New Horizons spacecraft will zoom past Pluto on Tuesday. And mission managers are confident that they have aimed precisely enough that the spacecraft, traveling 31,000 miles an hour, will pass through a rectangle just 60 miles by 90 miles at its closest approach to Pluto.

In terms of accuracy, that's like driving from New York to San Francisco and ending up within about five inches of the parking spot you had selected before setting out.

Pay no attention to me. My memory is clearly turning into a sieve.

Still. DAMN IMPRESSIVE WORK!

 

[Keith&Co.]

He's saying there still haven't been any probes beyond the moon.

But Tom and I are saying it doesn't make sense to assume that we'll NEVER have accurate images of Mars. Unless there's some sort of impenetrable wall around the Earth/Moon system that Cerberus hasn't told us about (though hinted at in Genesis), we'll get there eventually.
If the first (real) Mars mission finds proof of fraud, then all the other frauds will be revealed and generations of frauds will come crashing down. So the only way to ensure their jobs, and the jobs of the ones who came after them, would be to get real pictures for the fraudulent effort.

Thus we have no accurate images of Mars, the fake is fine.

Ticking Time Bombs of Exposure are not 'fine.' It makes no sense for a government agency to just go out and ensure that it will one day be proven a laughingstock.

 

[Loren Pechtel]

And from 'clutching at straws' we now descend into sarcasm. Well I always expect that - it's what those who realise they're losing an argument eventually resort to. Here are a few questions for you though, before I bow out - I'm intelligent enough to know that you can't argue against a closed mind - 1) Why didn’t NASA allocate more time for the probe do a few orbits of Pluto and take more photos – why just take the one with the ‘heart-shape’ in the momentary fly-by?

Energy. How do you propose that the probe stop to do those orbits? It's going like a bat out of hell, the fastest thing we have ever launched. To orbit it would have had to shed almost 8 miles/second of velocity. Pluto doesn't have enough atmosphere to do that with aerobraking, it would have to be done with rockets. Now, that's about the energy required to launch from Earth.

Now, New Horizons weighs 1,054 pounds. The third stage booster that boosted it after reaching escape velocity appears to weigh 4,660 pounds--thus the booster pushed 5,714 pounds to escape velocity. How much did that booster weigh?

1,291,400 pounds. Thus that booster weighed 226x the weight of what it launched. Want to stop at Pluto? You'll need to send along a booster with that much oomph. The third stage is long gone, we only need to look at New Horizons itself. 1,054 pounds * 226 = 238,204 pounds. The launch booster was 1225x the arrival weight, to launch something this heavy we need a booster of 291,799,900 pounds. That's about 1 1/2 aircraft carriers.

Oops the main engine of the Atlas is burns RP-1/LOX. RP-1 will freeze out by Pluto, the LOX will long since have evaporated. Neither propellant is useable in deep space. The LH2/LOX of the Centaur second stage fares even worse, both tanks boil dry.

In reality it carries hydrazine as it's propellant, using a catalyst to crack it in the rocket engine. This gives an ISP of about 220, 1/3 less than the performance of RP-1/LOX and half the performance of LH2/LOX. It has a performance similar to the strap-on boosters on the Atlas. Unfortunately, I don't have the overall ISP for the stack and I don't feel like taking the time to work the whole mess out. It's safe to conclude that it's well above the performance of the hydrazine, though--that means the rocket needs to be substantially larger.

Even without considering the effect of the weaker fuel we are still looking at around 3/4 of the total mass ever thrown into space to accomplish this. I would be very surprised if the actual answer came in less than the total amount ever launched into space. The rocket equation is absolutely brutal when dealing with delta-v requirements this high.

Yes, we could have sent it out slower so it didn't need so big a booster to stop. The same booster that launched it could have put it on a minimum energy transfer orbit which would have left it with enough to stop and orbit at the other end. Unfortunately, this would have taken 120 years. (The minimum energy orbit takes 1/2 the orbital period of the more distant body.)

2) What’s the difference between liquid water and er water? 3) If the ‘climates’ on Pluto and Mars are so hostile to life that mankind couldn’t live there, what was the point of the missions? Why not use the funding to build a colony on the moon? And the Philae thing - when it bounced after first landing on the asteroid, how come the asteroid was still there when it came back down when asteroids travel at 280.000mph? If I think of any more questions I'll get back to you!

Colonization isn't the only mission in space.

Also, note that a cold "climate" is no big deal for colonization on an airless body. The limits on colonization of the moon come down to the availability of certain elements--which are probably best obtained from the asteroid belt.

As for "liquid water" vs "water"--water in any form is fine for supplying raw materials for a colony. Also, planetary scientists are not going to refer to solid H20 as "ice"--there are plenty of other ices they deal with. They'll refer to it as "water ice", or in a situation where it's obviously frozen they might even just say "water".

 

[Loren Pechtel]

Good question!

http://www.skyandtelescope.com/astronomy-news/new-horizons-navigating-to-pluto-040320154/

Good answer. I'll simply add that New Horizons also has tiny engines that allow it to make simple course corrections if the engineers determine that it's getting off course.

But for the most part, New Horizons is a bullet with on-board cameras. I saw in a documentary last week that NASA engineers had estimated beforehand exactly where New Horizons would be when it reached Pluto. And after nine years of interplanetary travel and one Jupiter slingshot, the probe missed the target that they had estimated. . .

By one inch.

That is truly an impressive feat of engineering. I'm so glad I got to witness it.

Inch?

Then their location of Pluto was off because it missed it's target by several miles.

 

[Loren Pechtel]

The probe is moving, they have to take their measurements all at once. They can't wait 6 months like they do for parallax on nearby stars.

Two dishes/arrays at opposite ends of Russia could take measurements of the location of the signal simultaneously. The amount they disagree on the celestial coordinates of the source gives the parallax, which is then converted directly into minimum distance. This is not hard to do.

I'm not questioning this, I'm just questioning whether the accuracy is sufficient to put it near Pluto.

 

[skepticalbip]

Good answer. I'll simply add that New Horizons also has tiny engines that allow it to make simple course corrections if the engineers determine that it's getting off course.

But for the most part, New Horizons is a bullet with on-board cameras. I saw in a documentary last week that NASA engineers had estimated beforehand exactly where New Horizons would be when it reached Pluto. And after nine years of interplanetary travel and one Jupiter slingshot, the probe missed the target that they had estimated. . .

By one inch.

That is truly an impressive feat of engineering. I'm so glad I got to witness it.

Inch?

Then their location of Pluto was off because it missed it's target by several miles.

They weren't aiming to collide with Pluto. They were aiming for a close approach so they could take high resolution pictures as they zipped by. They must have been damned close to where/when they planned to be with respect to Pluto because Pluto was exactly where they expected it to be when they pointed the cameras there. All Pluto's moons were exactly where they were expected to be with respect to the probe too.

 

[skepticalbip]

Two dishes/arrays at opposite ends of Russia could take measurements of the location of the signal simultaneously. The amount they disagree on the celestial coordinates of the source gives the parallax, which is then converted directly into minimum distance. This is not hard to do.

I'm not questioning this, I'm just questioning whether the accuracy is sufficient to put it near Pluto.

The accuracy is sufficient for NASA to track and determine if or how steering correction is required.

 

[Malintent]

I very much doubt 1 inch story. First of all, such precision is not necessary and second, 1 inch with reference to what? surface of Pluto? but it's not defined that well. it has mountains and valleys mile(s) high/deep.

.. with respect to the planned path...

It does sound to me like 1 inch is beyond the degree of numerical significance.

"missed it by an inch" is also a common expression for "soooo close". So I would not discount the possibility that someone (as usual) takes common expressions as scientific explanations and rejects claims based on common alternatives of the meaning of expressions.

"You can't measure distance to that degree of precision" as a response to "we missed our mark by an inch"
may be like...
"the big BANG couldn't have happened" as a response to "sound cannot travel in a vacuum"

 

[Malintent]

For anyone that is interested in really learning about how hard it is to travel throughout our solar system in a very fun way, check out the FREE demo of the space simulation game, Kerbal Space Program (KSP) here -> https://kerbalspaceprogram.com

It is a fantastic game (available on Steam, by the way), lots of mods available, but the base game is simply fantastic.

Suffice to say, without reading about orbital mechanics, you will be hard pressed to so much as get a rocket out of atmosphere... never mind establishing a circular orbit, performing rendezvous, plotting transfer orbits to the moons (yes, I said moons - their star system is a bit different than ours, heh), landing in various gravities and atmospheres, returning home, transferring to other planets... mining resources to produce fuel, creating satilites for science and research, creating space stations....

And all of that has to be built from basic parts unlocked by doing science missions from an extensive tech tree.

best.space.game.ever. And super accurate. Just look at the "readme" patch notes. Exceprt (to see the level of detail in this):

Bug Fixes and Tweaks:
Thermal:
* Vessels which are splashed will now have much higher convective coefficients making them cool to ambient temperature faster.
* Removed node size from being taken into account for stack occlusion. Added custom drag cubes for remaining hollow parts.
* Parachute heating/burning.
* Fix for bug in FI dealing with unpacking vessels at analytic warp (>=1000) rates.
* Fixed conduction on service bays. Added Module Conduction Modifier to help service bays not incinerate their contents & configs updated
* Updated emissivity for spaceplane configs.
* Lowered heat production on LV-N.

Resources:
* Replaced overheat mechanic of the ISRU and drills with a skill-based mechanic.
* Removed Overheat Throttle mechanic.
* Increased mass of Ore tanks to match wet/dry ratio of stock tanks.
* New values for physics global drag and lift multipliers.
* Added a CoP offset calculation to procedural fairings
* Fix for the aero debug drag arrows switching directions. Added body lift arrows (cyan)
* Fixed occlusion on mk2 docking port.
* Fix for Laythe's atmosphere.

Solar Panels:
* Solar panels now use the proper inv square from FI's solar flux.

... snip ....

 

[Shadowy Man]

Two dishes/arrays at opposite ends of Russia could take measurements of the location of the signal simultaneously. The amount they disagree on the celestial coordinates of the source gives the parallax, which is then converted directly into minimum distance. This is not hard to do.

I'm not questioning this, I'm just questioning whether the accuracy is sufficient to put it near Pluto.

I stated in an earlier post the parallax for Pluto across a Russian baseline.

 

[GenesisNemesis]

Have I talked about how conspiracy theorists are paid shills yet?

 

[Loren Pechtel]

Inch?

Then their location of Pluto was off because it missed it's target by several miles.

They weren't aiming to collide with Pluto. They were aiming for a close approach so they could take high resolution pictures as they zipped by. They must have been damned close to where/when they planned to be with respect to Pluto because Pluto was exactly where they expected it to be when they pointed the cameras there. All Pluto's moons were exactly where they were expected to be with respect to the probe too.

They were aiming for a point in space a certain distance from Pluto. They didn't hit that to within an inch, they couldn't even measure whether they hit it to an inch.

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I'm not questioning this, I'm just questioning whether the accuracy is sufficient to put it near Pluto.

The accuracy is sufficient for NASA to track and determine if or how steering correction is required.

NASA has the take from it's on-board cameras and can actually understand the signals. I'm figuring Russia has neither of these.

 

[barbos]

There is no real need to understand the signal to triangulate the position. As I calculated, it's perfectly doable to put the source of the signal into vicinity of Pluto (with 1% or better accuracy) using few radio-telescopes over Russia. As for precise tracking and navigation, then it's clearly not enough for that.

 

[Cerberus]

Cerberus, where's your proven and tangible evidence for the claims you've made about CGI graphics, jobs for the boys, that all NASA (and other space agencies) probes beyond the moon don't actually exist, about the hiring process at NASA, etc.?

Why do you refuse to provide any evidence for any of your many claims after you specifically stated that you only believe things that you have proven and tangible evidence for?

One can't prove a negative - it's up to you to convince me I'm wrong.

 

[Cerberus]

Good question!

http://www.skyandtelescope.com/astronomy-news/new-horizons-navigating-to-pluto-040320154/

How do we navigate and home in on the aim point? First, we must determine where the spacecraft is — and where it's going — to high accuracy. To achieve this, we combine radio tracking of the spacecraft's trajectory (using NASA's Deep Space Network of tracking antennas) with a technique called optical navigation, in which New Horizons uses an onboard imager called LORRI to record the precise positions of Pluto and its satellites against background stars.

Thanks for that, but I'm simply unable to get my head around 'the value of the occultation of Earth'. Does it involve using radio waves? If so, who is the transmitter for radio-wave occultation/bending experimentation, New Horizons or Earth? High-gain as Earth-based dishes may well be, there’s got to be a significant wide 'beam' by the time Pluto is reached. But another question (well you did say 'feel free to ask'). Returning to the Philae: you gave me the scenario whereby if I jumped in an equatorial locale (where the Earth is rotating at c. 1000mph), I'd come down on precisely the same spot; but would I not come down on a different spot if I could jump say, a mile high? The reason I ask is because (as I understand it) the lander first had to locate the asteroid, then catch up with it - which begs the question If the asteroid is travelling at 280.000mph, how fast would the craft itself need to be travelling to catch up with it? - then need to slow down to match the speed of the asteroid at the moment prior to landing, then presuming the 'bounce' timeline was measured in terms of minutes the craft would have lost momentum whereas the asteroid didn't, meaning that the craft would need a restoration of thrust in order to catch up with the asteroid again? So presuming the required alteration would need to be via radio signal from the control centre, which evidently takes some hours, how much further did the asteroid travel before the lander was able to make its final landing?

 

[bilby]

Good question!

http://www.skyandtelescope.com/astronomy-news/new-horizons-navigating-to-pluto-040320154/

Thanks for that, but I'm simply unable to get my head around 'the value of the occultation of Earth'. Does it involve using radio waves? If so, who is the transmitter for radio-wave occultation/bending experimentation, New Horizons or Earth? High-gain as Earth-based dishes may well be, there’s got to be a significant wide 'beam' by the time Pluto is reached. But another question (well you did say 'feel free to ask'). Returning to the Philae: you gave me the scenario whereby if I jumped in an equatorial locale (where the Earth is rotating at c. 1000mph), I'd come down on precisely the same spot; but would I not come down on a different spot if I could jump say, a mile high? The reason I ask is because (as I understand it) the lander first had to locate the asteroid, then catch up with it - which begs the question If the asteroid is travelling at 280.000mph, how fast would the craft itself need to be travelling to catch up with it? - then need to slow down to match the speed of the asteroid at the moment prior to landing, then presuming the 'bounce' timeline was measured in terms of minutes the craft would have lost momentum whereas the asteroid didn't, meaning that the craft would need a restoration of thrust in order to catch up with the asteroid again? So presuming the required alteration would need to be via radio signal from the control centre, which evidently takes some hours, how much further did the asteroid travel before the lander was able to make its final landing?

Lost momentum to what? Your grasp of physics seems to be between 400 and 4000 years out of date. Momentum is conserved in a closed system; space is a vacuum. Objects in space do not lose momentum. They can change their momentum only by impacting with other objects, interaction with the gravitational field of other objects, or ejecting parts of themselves. In all of these cases, the total momentum of the system (ie of all of the parts) before and after remains the same (a rocket gains momentum only because its propellant gains equal and opposite momentum, for example).

 

[DBT]

Cerberus, where's your proven and tangible evidence for the claims you've made about CGI graphics, jobs for the boys, that all NASA (and other space agencies) probes beyond the moon don't actually exist, about the hiring process at NASA, etc.?

Why do you refuse to provide any evidence for any of your many claims after you specifically stated that you only believe things that you have proven and tangible evidence for?

One can't prove a negative - it's up to you to convince me I'm wrong.

You happen to be making a positive claim: that space exploration beyond the moon has all been faked. As it is you making the claim, it is you who should be backing your claim with evidence.

 

[Cerberus]

Thanks for that, but I'm simply unable to get my head around 'the value of the occultation of Earth'. Does it involve using radio waves? If so, who is the transmitter for radio-wave occultation/bending experimentation, New Horizons or Earth? High-gain as Earth-based dishes may well be, there’s got to be a significant wide 'beam' by the time Pluto is reached. But another question (well you did say 'feel free to ask'). Returning to the Philae: you gave me the scenario whereby if I jumped in an equatorial locale (where the Earth is rotating at c. 1000mph), I'd come down on precisely the same spot; but would I not come down on a different spot if I could jump say, a mile high? The reason I ask is because (as I understand it) the lander first had to locate the asteroid, then catch up with it - which begs the question If the asteroid is travelling at 280.000mph, how fast would the craft itself need to be travelling to catch up with it? - then need to slow down to match the speed of the asteroid at the moment prior to landing, then presuming the 'bounce' timeline was measured in terms of minutes the craft would have lost momentum whereas the asteroid didn't, meaning that the craft would need a restoration of thrust in order to catch up with the asteroid again? So presuming the required alteration would need to be via radio signal from the control centre, which evidently takes some hours, how much further did the asteroid travel before the lander was able to make its final landing?

Lost momentum to what? Your grasp of physics seems to be between 400 and 4000 years out of date. Momentum is conserved in a closed system; space is a vacuum. Objects in space do not lose momentum. They can change their momentum only by impacting with other objects, interaction with the gravitational field of other objects, or ejecting parts of themselves. In all of these cases, the total momentum of the system (ie of all of the parts) before and after remains the same (a rocket gains momentum only because its propellant gains equal and opposite momentum, for example).

That's interesting, and I'd like to learn more about it. Can you recommend a link please?

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One can't prove a negative - it's up to you to convince me I'm wrong.

You happen to be making a positive claim: that space exploration beyond the moon has all been faked. As it is you making the claim, it is you who should be backing your claim with evidence.

I can't prove my theories any more than you can.

 

[barbos]

To slow down from 14 km/sec one would need to increase mass of the probe by a factor of exp(14./4.4)=24.09.
4.4 is a exhaust velosity for H2+02 engines.
So everything would have to be at least 25 times heavier (in reality 50 times). Nobody have such rockets.

The only viable way to get to land/orbit Pluto in reasonable amount of time is nuclear propulsion.

Mercury is pretty close but it has the similar problem where you have to slow down somehow and unlike Pluto there is no option of slow speed launch because it's inner planet and potential energy is lower there compared to Earth. So it took very fancy trajectory with bunch of gravity assists using Venus and Mercury itself to get to orbit it.

So if NASA claimed orbiting Pluto that would have been clear indication of fraud unless they show they can build descent nuclear propulsion.

 

[bilby]

Lost momentum to what? Your grasp of physics seems to be between 400 and 4000 years out of date. Momentum is conserved in a closed system; space is a vacuum. Objects in space do not lose momentum. They can change their momentum only by impacting with other objects, interaction with the gravitational field of other objects, or ejecting parts of themselves. In all of these cases, the total momentum of the system (ie of all of the parts) before and after remains the same (a rocket gains momentum only because its propellant gains equal and opposite momentum, for example).

That's interesting, and I'd like to learn more about it. Can you recommend a link please?

Sure.