New Horizons Probe's Images of Jupiter

SeaDour writes "The Pluto-bound New Horizons space probe, launched a little over a year ago, recently succeeded in passing through a narrow navigational keyhole by Jupiter. Using the gas giant's tremendous gravity, the craft now has a significant boost toward its final destination, shaving three years off the time it would otherwise spend en-route. As it passed through the Jovian system, the probe took some fantastic images of the neighborhood, including detailed observations of erupting volcanoes on Io, time-lapse photography of Jupiter's tumultuous atmosphere, and the faint ring system that was first discovered in Voyager photography. These new images prove the capabilities of the small probe, which is set to reach Pluto in 2015."

Gravitational slingshot

And as we all know, it is Jupiters orbital velocity that gives the spacecraft its speed boost, not Jupiter's gravitational field. See: here [wikipedia.org].

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It must be all that centrifical force :P

Re:Gravitational slingshot

You don't know what you are talking about, and the Wikipedia article is screwed up as well. The Wikipedia article claims that no momentum can be gained passing by a stationary massive object. I'll give a simple counterexample. Drill a bore straight through the diameter of the Earth. If you pull a vacuum in this theoretical bore and drop a spacecraft into it, it will exhibit simple harmonic motion. What is interesting is that the object will have the greatest absolute momentum at the center of the Earth. Now take a rocket and fire only towards the center of the planet when you pass outwards from the center--not inwards. If you do this long enough you will reach escape velocity and say bye bye to the planet. Do your math calculating the momentum and you will find that you have got more absolute momentum that just from the rocket alone.

Why is this so? First, momentum is conserved, the extra momentum is in the Earth in the opposite direction. Second, you were able to amplify your momentum because you minimized the time that your spacecraft felt the strongest gravitational fields pulling it back towards the planet when you were heading outwards (by using your rocket). But you maximized the time that your spacecraft felt the strongest gravitational fields pulling you into the planet when you were heading inwards coasting (because your rockets only fire when you are heading outwards). Strictly speaking the Earth does not give a great example of how this would work since the highest gravity of the non-uniform density Earth is about 1000 miles under the surface (and is 0 at the core due to Gauss' Law). But it may be more obvious if you arbitrarily move the 'bore' or path of the spacecraft so that its closest approach to the Earth is 2000 km above the surface. In this case it is obvious that you would coast until you got to the closest approach to the Earth and then fire your rockets for a few minutes to minimize your time in the highest gravitational field.

This is sort of what a flyby could do if it didn't use its rockets and the planet had a high orbital velocity. Due to the orbital velocity alone you could target your spacecraft so that the planet recedes minimizing your gravitational interaction on the flip side (which requires you to fly by close enough to change paths a little bit since no path change would not do anything even with a high speed massive object). Of course using rockets and this method together are better.

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You don't know what you are talking about, and the Wikipedia article is screwed up as well. The Wikipedia article claims that no momentum can be gained passing by a stationary massive object. I'll give a simple counterexample. Drill a bore straight through

Re:Gravitational slingshot

This is for the same reason as you give: it spends less time being slowed on the way out because its speed was higher than when it was falling inward.

Nope. Think about it in terms of potentials and you'll see why this is not correct. The rocket's loss in gravitational potential energy coming out of the hole is exactly equal to the gain it got going in. It doesn't matter how fast it was moving at the start: the potential changes are determined solely by the source configuration because gravity is a velocity-independent force.

Remember: Newtonian energy change is equal to the integral of force over distance, not time.

The GP is correct in that mass discharged by a rocket deep in a gravity well has an added benefit. In terms of energetics you can think of this as being due to the gain in energy you get as the expended fuel falls into the well that you don't have to pay back when the spacecraft comes out of it.

But there it is also the case that the orbital velocity of the planet generally gives a larger effect, although of course it would be misleading and silly to claim that this is not due to the planet's gravity, because what else would be causing the interaction between the planet and the spacecraft? It is true that if the planet had no orbital velocity nothing very interesting would happen, but the same would be true if it had no gravity. Not that either condition is likely to pertain to real planets.

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Um... what? IANAPhysicist, but it seems to me the link you provided explains exactly that the gravitational field is used in this maneuver. True that it is combined with the orbital velocity, but without the gravitational pull, you have nothing.

Or were you

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Gravity is definitely involved, of course. However, it is just the "medium" through which the change in momentum is transferred. Jupiter's orbital momentum is reduced by the amount same amount as momentum gained by the satellite. Since momentum is a fun

Re:It's both, really

If Jupiter didn't exhibit a strong gravitational pull on the probe, it wouldn't be able to have a significant impact on the probe's orbital velocity.

If Jupiter were not moving w/r/t the sun and the probe, the probe's velocity w/r/t the sun would be no greater after the flyby than before.

The way I see it, both gravity and orbital velocity are necessary components of the gravitational slingshot, so it's fair to say that it's a combination of the two that give the spacecraft its speed boost.

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Agreed. Let's just see a pebble, or even an asteroid, in the same orbit do the same thing.

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Crikey, i never said Jupiter's gravitaional field wasn't a factor. But it's the orbital velocity that gives the spacecraft the extra push. Of course Jupiter's gravitational field is necessary to pull the spacecraft along in the first place, as the Wikipedi

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Can't people read between the lines or do I have to spell out even the bleedin' obvious?

You're posting on a site full of techies, well known for their pedantry and exhaustive attention to detail*, and you're surprised that people are pulling you up because

the waiting game?

So... what do the scientists do while they're waiting for the darn thing to get there?

A watched-probe never gets to pluto.

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Kinda makes you wonder right.. Unfortunately, the probe doesn't fly itself. It needs occassional course corrections and all that stuff is worked out on the ground. So how much money did it cost to pull staff off other projects and put em on this Jupiter

Re:the waiting game?

Probe has a finite design life. Save three years, improve the chance it will work when it's needed.

Re:the waiting game?

So how much money did it cost to pull staff off other projects and put em on this Jupiter diversion? Is it really economical to pop by just to pick up 3 years? It's not like there's a time to market here.

There is a deadline here, and the deadline is a natural one. Right now Pluto is near its perihelion, which means it is (just barely) warm enough to have an atmosphere. There are many many things you can learn scientifically from an atmosphere. However, if the space probe takes too long to arrive at Pluto, the atmosphere will be gone by the time it gets there. In that case, we'll have to wait a cool 200 years before Pluto comes around to perihelion again.

Quoting space.com [space.com]:

Scientists believe that as Pluto continues its 248-yearlong orbit around the sun, its tenuous atmosphere eventually will freeze and collapse to the surface. Pluto has been racing away from the sun since its closest approach in 1989 and scientists do not know how much time remains before Pluto's atmosphere collapses. Once that happens its atmosphere is not expected to re-emerge for about 200 years.

"Some people think its 20 years off and some people think its five years off," said Stern. "No one really knows when Pluto's atmosphere will snow out and collapse."

Obligatory answer

No it does not run Linux.

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Nope, but if it ran windows, it would have crashed into the sun on it's last maneuver...

Which is good because if windows was installed, the photos taken would not be viewable after downloading them as the owners certificate would not match the original and

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I can't imagine that at all without an old korean holding a bowl of hot grits.

Another time-saving measure

Whoop-de-do, slingshotting around Jupiter. They could have shaved a lot more time off the trip by slingshotting around the sun. :)

But that method is usually only reserved for Starfleet emergencies.

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I only wish they were doing some sort of "counter-slingshot" manoeuvre once they got to Pluto so the probe could stick around and study the planet, instead of merely flying by and heading out of the solar system.

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Whoop-de-do, slingshotting around Jupiter. They could have shaved a lot more time off the trip by slingshotting around the sun. :)

But that method is usually only reserved for Starfleet emergencies.

Oh yeah, like that would work. After the probe went back i

Damn

I always thought of New Horizons as an outer system probe. But with all that lag time, I should have realized..

(wait for it)

..it was Io-bound too!

Stereo images?

I hope they have some or will have some.
I was looking around the many NASA pages and discovered that there are a LOT of 3D stereoscopic images online from Mars, the new Solar STEREO twin satellites, etc.. I found so much stuff that I decided to order a pr

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I don't think Jupiter is that suitable for stereographs. From the probe's perspective, the atmospheric features are generally pretty flat. Look at those near the edge of the sunlight portion (sunset or sunrise): they barely show any relief. And, it didn't

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In fact they often use deep depleted CCD's for those lovely images. Broad spectral response from deep IR *(not heat) through UV. Slice in 5 filters and you cover a lot of ground optically.
-nB

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Here you go:

{_@_}

Re:Great!

Seriously? We launch a gajillion dollar probe, chance it in a sling around the largest planet in our solar system to only save 3 years, and we get black and white photos that have more noise than my cell-phone's camera!?

This is how the first computers looked like [epemag.com]. And this is how their "hard drives" looked like [fireinthevalley.com].

It was expensive as hell, and the returns were minimal. They dared to do it first, and to improve upon their experience, so today the neighbor kid can whine how he has to wait entire 7 seconds for his physically accurate and photo realistic 3D racing car simulator game to load the entire race track, complete with realistically behaving crowd, plants and atmospheric effects.

NASA reached Pluto with a remotely controlled probe deep in space. You ranted in Slashdot. Congratulations to both for your great achievements.

Re:Great!

From the JPL website:

"This is the last of a handful of LORRI images that New Horizons is sending "home" during its busy close encounter with Jupiter - hundreds of images and other data are being taken and stored onboard. The rest of the images will be returned to Earth over the coming weeks and months as the spacecraft speeds along to Pluto."

Wait some time for the high-res...they're more interested in making sure the thing works above all else.

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Believe it or not the goal of these missions is to gather scientific data, not provide you with a pretty screen saver ;-)

Re:Great!

Ralph: A Visible/Infrared Imager for the New Horizons Pluto/Kuiper Belt Mission [swri.edu]

"MVIC is composed of 7 independent CCD arrays on a single substrate. It uses two of its large format (5024x32 pixel)
CCD arrays, operated in time delay integration (TDI) mode, to provide panchromatic (400 to 975 nm) images. Four
additional 5024x32 CCDs, combined with the appropriate filters and also operated in TDI mode, provide the capability
of mapping in blue (400-550 nm), red (540-700 nm), near IR (780-975 nm) and narrow band methane (860-910 nm)
channels."

You did know that cameras like this take colour shots by merging multiple exposures with different filters applied, right? They're probably using their limited bandwidth to retrieve single exposures from each shot to get a quicker overview of what they've got.

Re:Great!

Ding, ding, ding!

NASA (tag-teaming with fweeky): 1
Slashdot armchair cynic: 0

I don't suppose the GP has ever tried taking a picture of Jupiter with his fancy camera phone, either. He might find it a little blurry, very grainy, and surprisingly dark. Add in a little radiation and interference from moving through Jupiter's magnetic field and then transmit it 150 million miles, and layer on top of it spectrographic and radar data from the other instruments and you realize the OP's $450 (mass-produced price) cell phone with it's 3mm lens doesn't even count as a toy in comparison.

When you consider that the best images we have of Pluto currently (from the Hubble) are about 0.0005 megapixels of surface data and that New Horizons will pass a fraction of the distance from Pluto that it did from Jupiter, you begin to understand how much bang-for-the-buck this mission has to offer in understanding a body that may be one of the most numerous and least understood type of objects (KBO's) in our solar system.

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Your $450 dollar cellphone has the collective design advantages ("shortcuts," from a spacecraft design POV) of not dealing with hard radiation, operating in a very small temperature range, having heat dissipation via air, recharging frequently from earth-b

You forgot one...

Also, and perhaps most importantly, prior to use, it can be tested in an environment very similar to the one in which it will operate. For space probes - not so much. That's one reason why they are so very, very conservative.

Re:Great!

Man... I guess that all of these scientists are really dumb and they should start taking your opinion seriously... right?

You do not launch a god dam cell phone camera on a billion dollar mission and hope to hell that it works.

Do you have any idea at all what it costs to qualify flight hardware?

Take your cost, no matter what it is, and add a couple of million to it. That is at best a starting point. That includes the fact that your cell phone would not work in a high radiation environment. The CCD would be blasted by the radiation environment.

Remember that the launch cost alone is outrageous. The instrument costs are a very small part of the total cost of the mission. A typical instrument costs around 15 million. That includes the design, development, construction, qualification, and scientific analysis of the data.

Before you pass judgment on what is and is not acceptable, please acknowledge that you are not qualified to pass such judgment.

Re:Great!

I was actually looking forward to seeing what comes back from the probe. But I hear Pluto is a dwarf planet...the pictures probably won't show much, since dwarves live underground.

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Because if you don't get immediate benefit from it, it must be crap?

Remember, once upon a time, when space was exciting & people wanted to learn about it, and send people there, and get some rocks back?

Re:Great! (You must be joking)

You're kidding right? All high-end scientific cameras are monochromatic (cameras for microscopy and astronomy). This is because a "color" CCD is essentially just an approximation of what a RGB image would look like. For scientific purposes, you do NOT want a fixed color imager to be adding or subtracting data. You want imaging at particular visible wavelengths (as directed by specific filters). If you want to make a color image, you can individually take pictures at 3 visible wavelengths (e.g. RGB) and combine them. This is what the Mars rovers do. Color doesn't automatically equate mean better. Sometimes it means you get prettier images, but they're rarely more valuable than imaging with specific filters. For example, infrared and UV can also be used to image. You don't get the pretty pictures except by false coloring, but you sure as heck get a lot of valuable measurements.

Nice attempt at a rant/trolling, but maybe you don't know what you're talking about.

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I think GP was ranting about the lack of entertainment value.

Interesting info though, thanks. Someone mod parent up.

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Congratulations. You have the distinction of being the only reply to my (apparently trollish) comment with any real information whatsoever. Everyone else just said, 'it costs a lot of money, duh!'

I was actually more worried about how grainy the images ar

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Seriously? We launch a gajillion dollar probe, chance it in a sling around the largest planet in our solar system to only save 3 years...

Correction: gravitational slingshot does not save time, it WASTES time. Fastest method is Hohmann transfer [wikipedia.org] but it requires prohibititive amounts of energy (rocket fuel).

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Correction: gravitational slingshot does not save time, it WASTES time. Fastest method is Hohmann transfer [wikipedia.org] but it requires prohibititive amounts of energy (rocket fuel).

Nope. The Hohmann transfer is generally the most fuel efficient way

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"Seriously? We launch a gajillion dollar probe, chance it in a sling around the largest planet in our solar system to only save 3 years"

a) slightshots are a pretty well tested maneuver

b) it provides additional observations that are valuable in themselves,

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"Seriously? We launch a gajillion dollar probe, chance it in a sling around the largest planet in our solar system to only save 3 years"

a) slightshots are a pretty well tested maneuver

b) it provides additional observations that are valuable in themselves, eg features on Io that have changed since Galileo last observed them.

c) 3 years gives us a chance to study Pluto's atmosphere before it freezes out as Pluto moves away from the sun.

d) How would you get there faster, Mr. Smarty Pants? I'm sure the good folks at NASA would love for you to enlighten them. They definitely haven't thought carefully about efficient travel across the solar system...

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If you're going to criticize the cost of the mission, perhaps you should put a more informed number to it: $650 million over some 15 years [wikipedia.org].

Relax, that's only moderately expensive as interplanetary probes go. Cassini-Huygens will top out at around $3

Re:asteroid field

The asteroid fields in Star Wars are not representative of any asteroid fields we are familiar with, just like Natalie Portman isn't representative of any woman who has ever talked to me.

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Yeah, 3rd paragraph from the article

The image also shows the much smaller symmetrical fountain of the plume, about 60 kilometers (or 40 miles) high, from the Prometheus volcano in the 9 o'clock direction.

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How long until there's pictures of Uranus?

Boys, you know what to do...
   

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I am hesitent to click any suspicious links regarding any probe going anywhere near that green planet that starts with a "U". I'll let somebody else test the link this time...

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wtf? I've always loved that poster, but where is there a misused apostrophe anywhere in the posting?

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We're on a mission to explore all the planets of our solar system. The project is scheduled to finish in 9 years time when a probe reaches the last unexplored planet. But, 7 months later, the IAU redefines the term "planet", and Pluto no longer counts.