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New Horizons Probe's Images of Jupiter

kdawson posted more than 7 years ago | from the by-Jupiter dept.

Space 86

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."

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Forget Jupiter (-1, Offtopic)

Anonymous Coward | more than 7 years ago | (#18325777)

I want new pictures of Uranus....

Re:Forget Jupiter (3, Funny)

Anonymous Coward | more than 7 years ago | (#18325915)

Here you go:

{_@_}

Acceleration (-1, Troll)

Anonymous Coward | more than 7 years ago | (#18325815)

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.

I use the same technique when walking around town. Walking's such a drag, but you find a fatty and if you time it right you can get a real boost when you pass them by.

Sucks when you mistime it and start orbiting them though. Especially the loud yanks... ...and this one time ... ah, i'm not saying anything more than 'black hole'.

Gravitational slingshot (5, Informative)

absolutely (1074008) | more than 7 years ago | (#18325861)

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] .

Re:Gravitational slingshot (1)

CrazyJim1 (809850) | more than 7 years ago | (#18325965)

It must be all that centrifical force :P

Re:Gravitational slingshot (4, Interesting)

Anonymous Coward | more than 7 years ago | (#18326199)

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.

Re:Gravitational slingshot (1)

inviolet (797804) | more than 7 years ago | (#18326531)

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.

Yes.

Furthermore, if the spacecraft in your example began with an initial speed into the gravity well, then it would not need a rocket boost in order to gain a net momentum from the passage through the well. 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.

That is why our space probes need not perform a burn during a slingshot maneuver.

Re:Gravitational slingshot (4, Interesting)

radtea (464814) | more than 7 years ago | (#18326737)

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.

Re:Gravitational slingshot (1)

More_Cowbell (957742) | more than 7 years ago | (#18326233)

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 suggesting the spacecraft was using a lasso?

Re:Gravitational slingshot (2, Informative)

camperdave (969942) | more than 7 years ago | (#18326853)

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 function of mass and velocity, and since neither the mass of Jupiter, nor of the probe is changed, the satellite's velocity boost comes at price of Jupiter's orbital velocity. So the original poster is correct.

Re:It's both, really (4, Informative)

Bastian (66383) | more than 7 years ago | (#18327083)

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.

Re:It's both, really (1)

Tablizer (95088) | more than 7 years ago | (#18327373)

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

Re:Gravitational slingshot (2, Funny)

absolutely (1074008) | more than 7 years ago | (#18327793)

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 Wikipedia article I linked to clearly states. Can't people read between the lines or do I have to spell out even the bleedin' obvious?

Re:Gravitational slingshot (1)

More_Cowbell (957742) | more than 7 years ago | (#18328539)

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

You must be new here.

Re:Gravitational slingshot (1)

Tim C (15259) | more than 7 years ago | (#18328917)

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 you didn't spell out exactly what's happening but left a little to interpretation?

(* And yet so often unwilling to use correct grammar, punctuation and spelling, apparently believing that it doesn't matter; the irony is not lost on me...)

the waiting game? (1)

rasputin465 (1032646) | more than 7 years ago | (#18325869)

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

A watched-probe never gets to pluto.

Re:the waiting game? (1)

QuantumG (50515) | more than 7 years ago | (#18325957)

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 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.

Re:the waiting game? (0)

Anonymous Coward | more than 7 years ago | (#18326111)

Not much, if most of the calculations and coding was done before launch/en route. You have guidance/nav/control people whose job it is to do this -- for every single spacecraft when needed. It's less of a "hey Bill, drop everything you're doing since we're getting damn close" and more of "hey Bill, in three year's you'll need to monitor some extra course corrections..."

Re:the waiting game? (-1, Offtopic)

Anonymous Coward | more than 7 years ago | (#18326425)

Riiiight, like Y2K. C'mon, am I the only one who made a few bucks fucking people over in 1999 "emergency"?

Re:the waiting game? (3, Insightful)

Beryllium Sphere(tm) (193358) | more than 7 years ago | (#18326257)

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

Re:the waiting game? (3, Informative)

David Jao (2759) | more than 7 years ago | (#18327953)

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."

Re:the waiting game? (0)

Anonymous Coward | more than 7 years ago | (#18333833)

In addition to what others have pointed (reduced chance of the probe dying, more substantial atmosphere), the Jupiter flyby also served as a dry run for the Pluto flyby. They only get one chance to do it, so they want to make sure it works. Your $650 million probe isn't worth much if you don't find a software bug until it gets there, or one of the instruments is on the fritz and you only have 2 weeks to get it working when it should be taking measurements continuously, as opposed to 8 years. It's a good dry run for the science team, too.

Plus, scientists are genuinely interested in seeing more closeup data from the Jupiter system. It's been 10 years since the Galileo mission ended, and no mission has had the opportunity to fly down Jupiter's magnetic tail, where New Horizons is now.

Besides, you're talking about a couple weeks of increased operations for a relatively large crew for the Jupiter flyby, compared to 3 years of extra project time for the smaller crew in charge of babysitting it during the flight. I doubt financially it works out much worse than even, but when you add in the extra experience operating the probe and the science return from Jupiter, it turns into a killer deal.

No time to market? Well, sort of. No one really wants to wait too long for data, plus you can expect some of project team members to migrate to other projects/organizations over 8-11 years. It's not critical if you have good documentation and procedures, but it's helpful to have the guys who built the thing around during crunch time.

Obligatory answer (0, Offtopic)

EmbeddedJanitor (597831) | more than 7 years ago | (#18325873)

No it does not run Linux.

Re:Obligatory answer (-1, Offtopic)

Anonymous Coward | more than 7 years ago | (#18325907)

No it does not run Linux.


Yes, but I can still imagine a beowulf cluster of these probes snapping pictures of Natalie Portman in Soviet Russia.

Re:Obligatory answer (0, Offtopic)

dreamchaser (49529) | more than 7 years ago | (#18325987)

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

Re:Obligatory answer (1, Funny)

Anonymous Coward | more than 7 years ago | (#18326011)

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 the DRM would not allow viewing unless they called 1-800-MICROSOFT and obtained a new key...

Problem is the license sticker is ON THE SPACECRAFT!

Re:Obligatory answer (1)

Rashdot (845549) | more than 7 years ago | (#18329093)

And the probe won't go near Uranus either.

Re:Obligatory answer (0)

Anonymous Coward | more than 7 years ago | (#18334129)

No, but it does run Unix [kinetx.com] .

Great! (-1, Troll)

Aladrin (926209) | more than 7 years ago | (#18325877)

Great, so we'll have crappy black & white photos of the non-planet Pluto as well! I -so- can't wait!

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!?

Re:Great! (5, Insightful)

suv4x4 (956391) | more than 7 years ago | (#18326015)

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! (0, Troll)

Aladrin (926209) | more than 7 years ago | (#18326095)

It was launched last year. If my $450 cellphone can have a color camera with decent resolution, so can this gajillion dollar probe. (Excuse me, it was only $650 million. Yeah, definitely couldn't have afforded a color camera.)

If this probe had been launched a decade ago, I'd have thought nothing of a B&W camera with shitty pics. But last year? Give me a freaking break.

And yes, I'm fully aware of what the original computers looked like. We passed that stage LONG ago for computers, rockets, and cameras.

Re:Great! (5, Informative)

Karthikkito (970850) | more than 7 years ago | (#18326157)

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.

Re:Great! (1)

CaymanIslandCarpedie (868408) | more than 7 years ago | (#18326391)

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

Re:Great! (4, Informative)

Fweeky (41046) | more than 7 years ago | (#18326411)

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! (4, Insightful)

iamlucky13 (795185) | more than 7 years ago | (#18327105)

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.

Re:Great! (1)

topical_surfactant (906185) | more than 7 years ago | (#18326457)

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-bound power sources, being replaceable, being disposable, not needing to survive the massive g-forces associated with a rocket launch, and being mass-produced.


Go build your shitty cell phone camera, from scratch, with the above restrictions, and get back to us on the cost.

You forgot one... (1)

benhocking (724439) | more than 7 years ago | (#18330469)

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! (3, Insightful)

Bad D.N.A. (753582) | more than 7 years ago | (#18326473)

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! (0)

Anonymous Coward | more than 7 years ago | (#18328431)

complete with realistically behaving crowd

Wow! They throw their beer cans at you? Anybody up in the stands flashing their titties for the camera?

plants

Roll up a fatty

and atmospheric effects.

It wasn't me, I swear.

Re:Great! (5, Funny)

psaunders (1069392) | more than 7 years ago | (#18326019)

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.

Re:Great! (1)

Tablizer (95088) | more than 7 years ago | (#18327757)

But I hear Pluto is a dwarf planet...the pictures probably won't show much, since dwarves live underground.

So do slashdotters.
     

Re:Great! (1)

Chmcginn (201645) | more than 7 years ago | (#18326061)

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) (5, Insightful)

posterlogo (943853) | more than 7 years ago | (#18326071)

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.

Re:Great! (You must be joking) (1)

glittalogik (837604) | more than 7 years ago | (#18326203)

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

Interesting info though, thanks. Someone mod parent up.

Re:Great! (You must be joking) (1)

Aladrin (926209) | more than 7 years ago | (#18329927)

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 are than the color, and you are correct that I was worried about color because I thought it was important. Optics is obviously not my field because I never considered taking images from several wavelengths (I had completely ignored things outside the human-visible range) and using them individually, instead of combining the data all at once.

On the other hand, 'pretty pictures' are an essential part of this mission as well. The ignorant public (apparently including me) doesn't feel the immediate impact of the mission without them. If we want to keep sending gajillion dollar probes, the public needs to see immediate and long-term benefits both. Immediately meaning pretty pictures and preliminary analyses, and long-term meaning real-world applications for the knowledge gained. PR is an unfortunate necessity for any business, including the government.

Re:Great! (You must be joking) (1)

Hynee (774168) | more than 7 years ago | (#18333933)

You obviously looked at the Jupiter Ring photo [jhuapl.edu] , it's faint, so the noise tells you they had push the camera to its limits to get that one. They probably had to process out the glow from Jupiter too, which adds extra noise.

Your cell phone has a small lens (low light) and small CCD (susceptible to noise), and must take the shot in milliseconds, so it will be noisy for the same reasons.

Re:Great! (0)

Fry-kun (619632) | more than 7 years ago | (#18326435)

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).

Re:Great! (0)

Anonymous Coward | more than 7 years ago | (#18326641)

Correction: gravitational slingshot does not save time, it WASTES time. Fastest method is Hohmann transfer but it requires prohibititive amounts of energy (rocket fuel).
Please be careful and read the articles you link to before you make claims.

From your wikipedia link it also states:

A Hohmann transfer orbit will take a spacecraft from low Earth orbit (LEO) to geosynchronous orbit (GEO) in just over five hours (geostationary transfer orbit), from LEO to the Moon in about 5 days and from the Earth to Mars in about 260 days. However, Hohmann transfers are very slow for trips to more distant points, so when visiting the outer planets it is common to use a gravitational slingshot to increase speed in-flight.
Last time I checked, Pluto was an outer planet (dwarf).

Re:Great! (1)

odyaws (943577) | more than 7 years ago | (#18327057)

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 to get from one elliptical orbit to another. You could clearly do it arbitrarily faster if you had unlimited fuel. Furthermore, if you're going to the outer planets and so have convenient targets to utilize (such as Jupiter), the gravitational slingshot can hugely reduce travel time without the penalty of using massive amounts of fuel (since you're robbing a bit of energy from the body you're slingshotting about). In the absence of such a slingshot the Hohmann transfer will be most fuel-efficient for a given specific impulse, but you're probably better off with an ion drive (a la DS-1 and the upcoming Dawn mission) with huge Isp, but not enough thrust to do a Hohmann transfer (since the HT assumes all your transfer impulse is applied at one instant). Then you just thrust continually at a low level for a long time.

Re:Great! (0)

Anonymous Coward | more than 7 years ago | (#18327523)

"(rocket fuel)."

I know this is proper and correct and all, but it just seems, looking at it; 'rocket fuel', so 1950s. Makes me want to dig out my Doc Smith paperbacks. Some day I'll look in the mirror and the fact that I'm over fifty will finally hit me. Won't be pretty...

Re:Great! (1)

uofitorn (804157) | more than 7 years ago | (#18328065)

According to the article you cited:

"...Hohmann transfers are very slow for trips to more distant points, so when visiting the outer planets it is common to use a gravitational slingshot to increase speed in-flight."

Re:Great! (0)

Anonymous Coward | more than 7 years ago | (#18328219)

Er ... no. A Hohmann transfer is the slowest and most fuel-efficient orbit possible in the absence of a gravitational slingshot. If you can use a slingshot, you may be able to reduce your trip time or fuel consumption - or, possibly, both. Without a slingshot, you always have the option of using more fuel in order to make the trip faster than a Hohmann orbit (until, of course, you run out of fuel).

Re:Great! (0)

Anonymous Coward | more than 7 years ago | (#18331823)

Methinks you ought to read that article again. Hohmann transfers are minimum-energy orbits which take lots of time, but use the least amount of energy to get there.

Sheesh.

Re:Great! (1)

ArbitraryConstant (763964) | more than 7 years ago | (#18326917)

"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.

Re:Great! (1)

odyaws (943577) | more than 7 years ago | (#18327103)

"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...

Re:Great! (2, Informative)

necro81 (917438) | more than 7 years ago | (#18331371)

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 $3.5-4 billion over the whole mission. The wildly successful Mars Exploration Rovers, especially since their mission has been extended much longer than expected, are about $1 billion. Mariner 4, the first probe to do a flyby of Mars (a significantly less-sophisticated mission), was about $100 million in 1960s dollars. $650 million is about as much that's lost to graft, corruption, fraud, and bribes in Iraq each month.

Aside from the probes that we have lost outright, the probes that have reached their destination intact have yielded mountains of data and plenty of pretty pictures. There will be much more data coming back to earth from the flyby in the coming weeks. But keep in mind that, over the vast distances and relatively weak signal from New Horizons, the connection is fairly low-bandwidth. By the time of the Pluto flyby, you can expect that it will takes months or years to download the full dataset. So, please, have some patience.

joke's on them (1)

ILuvRamen (1026668) | more than 7 years ago | (#18325969)

I'm gonna build a faster probe and send it to laser etch "I'm a planet, dammit" in Pluto's crust before this one gets there hehehehe. Discover that!

asteroid field (0)

Anonymous Coward | more than 7 years ago | (#18326093)

Do these probes that are sent out towards pluto and further face any real dangers when passing through the asteroid field that exists between Mars and Jupiter? I haven't heard much concerning this before and Starwars would have me believe that the chance of successfully navigating an asteroid field is 1 in 43 million.

Re:asteroid field (0)

Anonymous Coward | more than 7 years ago | (#18326843)

in space, a bunch of asteroids packed "close" to each other are tens of millions of miles apart. not a real big chance of them sneaking up on you.

Re:asteroid field (1)

Tablizer (95088) | more than 7 years ago | (#18327621)

in space, a bunch of asteroids packed "close" to each other are tens of millions of miles apart. not a real big chance of them sneaking up on you.

I suppose it is *possible* for them to be close together like they are in movies, but not in our solar system. Well, except for the rings of saturn perhaps.

The Pioneer 10 and 11 probes to Jupiter were explicitly designed to test the passability of the asteroid field. Although they detected more dust grains, probes can generally survive. The debri there is spread rather thin from a probe's perspective. Smaller particles are probably washed away via gravity from bigger asteroids, Jupiter's gravity disturbance (resonance), and radiation pressure from the sun.
       

Re:asteroid field (4, Funny)

regularstranger (1074000) | more than 7 years ago | (#18327059)

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.

Re:asteroid field (0)

Anonymous Coward | more than 7 years ago | (#18327411)

Space probes are "unmanned", but not unpersoned. They are actually flown by annoying little boys who are very good at piloting due to their having a very high count of an impronouncable symbiotic organism that makes no sense and generally spoils the plot of the original trilogy.

Mushroom cloud? (0, Offtopic)

Dunwich (155562) | more than 7 years ago | (#18326183)

Did anyone else spot the mushroom cloud at "9 o'clock?"

Re:Mushroom cloud? (0)

Anonymous Coward | more than 7 years ago | (#18326305)

3rd paragraph?

Re:Mushroom cloud? (1)

christheday (683048) | more than 7 years ago | (#18327265)

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.

Re:Mushroom cloud? (1)

Tablizer (95088) | more than 7 years ago | (#18327683)

Did anyone else spot the mushroom cloud at "9 o'clock?"

Hmmm. Maybe Io's vulcanos are really a nuclear war? The moon does indeed look like [wikipedia.org] somebody nuked the bloody hell out of it. Perhaps we can use it for a new peace poster: "This is your planet on nukes".
     

Another time-saving measure (4, Funny)

Kingrames (858416) | more than 7 years ago | (#18326185)

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.

Re:Another time-saving measure (1)

camperdave (969942) | more than 7 years ago | (#18326945)

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.

Re:Another time-saving measure (1)

RoboRay (735839) | more than 7 years ago | (#18328727)

It's certainly possible to put a probe in orbit about Pluto, but to do so would require either: A) Travelling so slowly that it would take a decade or more longer for the probe to even GET to Pluto, or B) Carrying so much deceleration propellant that you would need a Saturn V (at least) to get the thing off the ground to begin with. Due to cost and time constraints, neither of those options were viable for this mission. But, maybe someday things will be different.

Re:Another time-saving measure (1)

trongey (21550) | more than 7 years ago | (#18331177)

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 in time it would be sending back the pix of Pluto before it took them. For that kind of money nobody wants blank negatives. Duh.

Damn (1)

Sloppy (14984) | more than 7 years ago | (#18326213)

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? (1)

pair-a-noyd (594371) | more than 7 years ago | (#18326387)

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 professional grade pair of 3D glasses for viewing it.

Re:Stereo images? (0)

Anonymous Coward | more than 7 years ago | (#18327291)

Here [putnamfurniture.com] you go.

Re:Stereo images? (1)

Tablizer (95088) | more than 7 years ago | (#18327499)

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 get close enough to the moons to really see mountains and craters in stereo, at least not dramatically. It generally takes a close, slow pass for good geography stereography.

Plus, the atmosphere of jupiter would probably move between frames to mess up visual triangulation. More interesting are movies of jupiter's atmosphere. I've seen some drafts from N.H., and they are pretty cool.

I have yet to see any color images, but it may be that nobody has got around to layering and calibrating the different filter images. (Most space space probes use filters to get different colors, not color-sensative pixel detectors. This both increases the resolution and allows more than just 3 colors.)
     

Re:Stereo images? (1)

networkBoy (774728) | more than 7 years ago | (#18328617)

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

Immature Joke Warning (-1, Redundant)

jmac1492 (1036880) | more than 7 years ago | (#18326779)

How long until there's pictures of Uranus?

Re:Immature Joke Warning (1, Funny)

Tablizer (95088) | more than 7 years ago | (#18327521)

How long until there's pictures of Uranus?

Boys, you know what to do...
   

To the Slashdot editors (-1, Offtopic)

babasyzygy (786926) | more than 7 years ago | (#18327295)

Please print this informative, helpful poster [angryflower.com] out and display it prominently in your offices.

Re:To the Slashdot editors (1)

Tablizer (95088) | more than 7 years ago | (#18327549)

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...

Re:To the Slashdot editors (1)

SeaDour (704727) | more than 7 years ago | (#18328115)

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

Re:To the Slashdot editors (1)

babasyzygy (786926) | more than 7 years ago | (#18329735)

Bah. The editors fixed the headline.

They're already welcoming probe overlords (1)

Tablizer (95088) | more than 7 years ago | (#18327817)

The probe is already so popular that they formed a religion around it [nhmin.org] .

moid 0p (-1, Flamebait)

Anonymous Coward | more than 7 years ago | (#18328325)

dying. SSe? It'js

Ha-Ha! (0)

Anonymous Coward | more than 7 years ago | (#18331193)

" At the time of the launch, Pluto was the only planet in the Earth's solar system that had not been visited by a spacecraft. However, seven months afterwards, Pluto was demoted to a dwarf planet (per the official definition of the International Astronomical Union), leaving the solar system with only eight major planets. About two-thirds the size of the Earth's Moon, relatively little is known about distant Pluto when compared to closer neighbors of the Earth. "

So we start out for the only planet that WE discovered, and it turns out it's not a planet at all!

Incidentally, I regularly drive my car home and 'pass through a narrow navigational keyhole ' (my garage) every day. It's easy if you are allowed to make course corrections during the journey. Does someone think that probes are aimed from the earth? What gives with this idea that getting a self-steering robot to hit a target as big as a planet is difficult?

Re:Ha-Ha! (1)

bzipitidoo (647217) | more than 7 years ago | (#18340631)

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. Mission Accomplished! That's what I call killer project management and innovative thinking! Only thing left is for the government to cut some waste by stopping the funding on this now unnecessary project. ;)
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