https://en.wikipedia.org/wiki/Juno_(spacecraft)

Juno is a NASA New Frontiers mission currently en route to the planet Jupiter. Juno was launched from Cape Canaveral Air Force Station on August 5, 2011 and is projected to arrive on July 4, 2016.[4][5][6] The spacecraft is to be placed in a polar orbit to study Jupiter's composition, gravity field, magnetic field, and polar magnetosphere. Juno will also search for clues about how the planet formed, including whether it has a rocky core, the amount of water present within the deep atmosphere, mass distribution, and its deep winds, which can reach speeds of 618 kilometers per hour (384 mph).[7]

Juno will be the second spacecraft to orbit Jupiter, following the Galileo probe which orbited from 1995–2003.

The Juno spacecraft is powered by solar arrays, commonly used by satellites orbiting Earth and working in the inner Solar System, whereas radioisotope thermoelectric generators are commonly used for missions to the outer Solar System and beyond. For Juno, however, three solar array wings, the largest ever deployed on a planetary probe, will play an integral role in stabilizing the spacecraft and generating power.



Mission duration 6 years total

Cruise: 5 years
Science phase: 1 year
Spacecraft properties
BOL mass 3,625 kg (7,992 lb)[1]
Power 400 W; two 55-ampere-hour lithium-ion batteries[2]




Scientific objectives

The Juno spacecraft's suite of science instruments will:[23]

Determine the ratio of oxygen to hydrogen, effectively measuring the abundance of water in Jupiter, which will help distinguish among prevailing theories linking the gas giant's formation to the Solar System.
Obtain a better estimate of Jupiter's core mass, which will also help distinguish among prevailing theories linking the gas giant's formation to the Solar System.
Precisely map Jupiter's gravitational field to assess the distribution of mass in Jupiter's interior, including properties of its structure and dynamics.
Precisely map Jupiter's magnetic field to assess the origin and structure of the field and how deep in Jupiter the magnetic field is created. This experiment will also help scientists understand the fundamental physics of dynamo theory.
Map the variation in atmospheric composition, temperature, structure, cloud opacity and dynamics to pressures far greater than 100 bars (10 MPa; 1450 pound/sq inch) at all latitudes.
Characterize and explore the three-dimensional structure of Jupiter's polar magnetosphere and its auroras.[24]
Measure the orbital frame-dragging, known also as Lense–Thirring precession caused by the angular momentum of Jupiter,[25][26] and possibly a new test of general relativity effects connected with the Jovian rotation.





(Juno's highly elliptical orbits in relation to Jupiter's magnetosphere)


Juno's planned polar orbit is highly elliptical and takes it close to the poles—within 4,300 kilometers (2,672 mi) (Jupiter's radius ~70000 km)—but then far beyond even Callisto's orbit (that is over 2 mil km).[32] Each orbit takes 14 days and the spacecraft is expected to complete 37 orbits until the end of the mission.

This type of orbit helps the spacecraft avoid any long-term contact with Jupiter's radiation belts, which can cause damage to spacecraft electronics and solar panels.[32][33] The "Juno Radiation Vault", with 1-centimeter-thick titanium walls, will also aid in protecting and shielding Juno's electronics.[34] Despite the intense radiation, JunoCam and Jovian Infrared Auroral Mapper (JIRAM) are expected to endure at least eight orbits, while the microwave radiometer should endure at least eleven orbits.[35] In comparison, Juno will receive much lower levels of radiation than the Galileo orbiter at its equatorial orbit.


Let's see what new things we will find out with Juno orbiting so close to Jupiter's clouds at times.

I want Io and Europa porn, will this provide any? Doesn't sound like it will.

You will have to wait half a century for this one but it will follow humans everywhere eventually. For now Jupiter's aggressive radiation makes intimate encounters very risky there. It would take a really big budget studio production. Its doable though if it were a priority for less than $3 bil. Or less than 30 bil in current system. I bet its feasible within current technology and a couple experimental designs away that 1 bil can accelerate to perfection to send 2 there and then back fast. Ion propulsion and strong boosters initially in a small space station type habitat spaceship that is heavily shielded. On the way there they can practice forever lol. If Caligula lived today it might be seen as proper ritual appreciation for https://en.wikipedia.org/wiki/Juno_(mythology) and NASA forced to plan accordingly.

Bleh whatever, they did Cassini Huygens for that amount of money 10 years ago, surely even if the U.S. won't do it some other country's space agency could prioritize Europa and Io missions.

Hey wait is this happening? https://en.wikipedia.org/wiki/Europa...-Flyby_Mission That's enough for a semi chub at least.

To be fair i will be shocked if we ever found life independent of earth (not taken there i mean by some space debris from here millions of years ago) in any of these systems that people fantasize about.

The universe would be full of life if that were the case. It would also be a very depressing outcome hinting intelligent life dies soon after technology, although other possibilities still exist but they require some universal coordination to remain secretive about it lol.

I don't care about finding life on Europa, it's just geologically interesting and Io ever more so.

Thats why they speak about life because of this activity (tectonics and tidal effects from Jupiter). You definitely need interesting chemical environments before life has any chance to start as it probably requires specific rare combinations of conditions to enhance certain probabilities.

Europa and Enceladus is said to have a lot of water (ice and maybe liquid due to tidal heating). Io is very interesting too.

To be fair i think if life existed in any of these systems in all likelihood it would be at least a few bil years old and in that time frame it would have had a chance to alter the moons further chemically and even have consequences on the surface and atmosphere. Life tends to find a way to adapt to harder environments or change them in order to do so lol.

Look at earth. The current result started from very hostile conditions that were gradually manipulated by life itself even if unconsciously. I think if it can start then it can go places and change some habitat substantially.

The heavy radiation there is a problem but below surface its a lot better even if still cold. Maybe near a volcano it can get interesting.

If indeed there are regions that the temperature is enabling liquid water below the surface and there is active chemistry with dependable energy sources one may argue that current extremophiles from earth would survive there without any need for solar radiation.


I want to imagine for example how life could alter the atmosphere of these systems (at rates higher than they lose it to space - these moons are like the size and gravity of our moon) trapping heat inside and assuming the internal heat generation methods with tidal effects.

Then conceivably after hundreds of millions of years the conditions for further diversity in life would become possible due to this gradual large scale action of the earlier life raising temperatures and altering radiation effects by thickening atmosphere. It happened that way here actually. Early very primitive but persistent in action life made possible future life with more interesting properties by simply modifying the initial environment towards directions that further chemical interactions became possible. So over time maybe the surface is altered that way even if all started inside. Solar radiation at this distance is about 30 times weaker than earth. But even that is something if the right atmosphere existed if the interior is losing energy at significant rates to create equilibrium at much higher temperatures.

I wonder how far one could take these systems using primitive life reactions in the right direction. I want to imagine the system starts with limited possibilities and over time life opens up further doors. There seems to be so much complexity that can emerge out of this if only the first steps were there.

Enceladus of course is in the Saturnian system so i only spoke about it because of the similar issues regarding tectonic activity, the water below surface possibly in liquid form and the unexplained internal heating. It is of course a much smaller moon (only 250km radius) so it couldnt sustain an atmosphere like the others if a biological process existed to supply the gases.

In these very cold systems internal heating is very important as the temperatures observed are at places higher than what solar radiation would justify so far from the sun. If for some reason there is a place in the moon that there is trapping of heat from other (internal) regions directed there due to the differential insulation in place you could have local regions of significantly elevated temperature vs the avg, possibly due to radioactive decay or tidal heating and maybe even some chemical processes, although these would have to be short lived and occasional/opportunistic/rare.

Here is how small Enceladus is by the way (brief break excuse for a cool pic for this minor tangent from the Jovian system exploration that is the main issue of the thread)



https://en.wikipedia.org/wiki/Enceladus
( 0.75 mil km^2 surface area so say 3 times the area of UK or a bit larger than Texas , still possibly prime real estate eventually due to water)

See how much larger is eg Io ;



https://en.wikipedia.org/wiki/Io_(moon)

Io (40 mil km^2 area or as much as the 2 American continents) enjoys by the way much more significant tidal friction heating, 200 times larger than the radioactive decay heat rate generation or about 10^14W total that is significant when compared with say the solar radiation power of ~4.4*10^14W at this distance which if you take into account its significant albedo of 0.63 (see how bright it is) it's only 1.8*10^14W from the sun that is absorbed. This implies that tidal heating alone is 30-40% of the total heat supplied to this system from sun or internal friction. This of course is all radiated back to space in thermal spectrum at the equilibrium temperature the system reaches locally at surface say 90-130K. Below surface its much warmer than that though.

(that was ~ 5 mil Km away ~5 days ago)

http://www.nasa.gov/image-feature/pi...-in-on-jupiter

"In the evening of July 4, Juno will perform a suspenseful orbit insertion maneuver, a 35-minute burn of its main engine, to slow the spacecraft by about 1,212 miles per hour (542 meters per second) so it can be captured into the gas giant’s orbit. Once in Jupiter’s orbit, the spacecraft will circle the Jovian world 37 times during 20 months, skimming to within 3,100 miles (5,000 kilometers) above the cloud tops. This is the first time a spacecraft will orbit the poles of Jupiter, providing new answers to ongoing mysteries about the planet’s core, composition and magnetic fields."

Live update now for the next few hours. It probably has started already in Jupiter but it takes 45-60 min for signals/information to get here or so.

http://www.nasa.gov/mission_pages/juno/main/index.html (press the video)

Welcome to Jupiter.

I did a brief calculation estimate using the details provided on how close it will be orbiting briefly Jupiter at times and it comes out having a speed of 60 km/sec at these close encounters basically lasting ~1 hour per close turn (periapsis) with distance only ~75000 km from Jupiter's center flying so low(4-5k km above clouds) and apoapsis over 2-3 mil km away in this extreme eccentricity orbit. That is some huge speed by the way briefly while there for a few hours so close to Jupiter until it makes a complete turn back away again for a few days back to apoapsis. Jupiter will be filling literally all the sky on one side there. Its similarly to how earth looks like from space station (in scale).

Also check out on Europa; (and some AI based future i imagine getting started there)

https://en.wikipedia.org/wiki/Europa_(moon)

"Subsurface ocean
Two possible models of Europa

Scientists' consensus is that a layer of liquid water exists beneath Europa's surface, and that heat from tidal flexing allows the subsurface ocean to remain liquid.[13][54] Europa's surface temperature averages about 110 K (−160 °C; −260 °F) at the equator and only 50 K (−220 °C; −370 °F) at the poles, keeping Europa's icy crust as hard as granite.[7] The first hints of a subsurface ocean came from theoretical considerations of tidal heating (a consequence of Europa's slightly eccentric orbit and orbital resonance with the other Galilean moons). Galileo imaging team members argue for the existence of a subsurface ocean from analysis of Voyager and Galileo images.[54] The most dramatic example is "chaos terrain", a common feature on Europa's surface that some interpret as a region where the subsurface ocean has melted through the icy crust. This interpretation is controversial. Most geologists who have studied Europa favor what is commonly called the "thick ice" model, in which the ocean has rarely, if ever, directly interacted with the present surface.[55] The best evidence for the thick-ice model is a study of Europa's large craters. The largest impact structures are surrounded by concentric rings and appear to be filled with relatively flat, fresh ice; based on this and on the calculated amount of heat generated by Europan tides, it is estimated that the outer crust of solid ice is approximately 10–30 km (6–19 mi) thick,[56] including a ductile "warm ice" layer, which could mean that the liquid ocean underneath may be about 100 km (60 mi) deep.[38][57] This leads to a volume of Europa's oceans of 3 × 10^18 m^3, between two or three times the volume of Earth's oceans.[58][59]

The thin-ice model suggests that Europa's ice shell may be only a few kilometers thick. However, most planetary scientists conclude that this model considers only those topmost layers of Europa's crust that behave elastically when affected by Jupiter's tides. One example is flexure analysis, in which Europa's crust is modeled as a plane or sphere weighted and flexed by a heavy load. Models such as this suggest the outer elastic portion of the ice crust could be as thin as 200 metres (660 ft). If the ice shell of Europa is really only a few kilometers thick, this "thin ice" model would mean that regular contact of the liquid interior with the surface could occur through open ridges, causing the formation of areas of chaotic terrain."

See also

https://en.wikipedia.org/wiki/Extrat...l_liquid_water

Can you imagine how important this is longer term (100-200 years from now) for civilization if indeed it has 2+ times more water than Earth? Water means fusion eventually due to Deuterium, it means rocket propulsion also in conventional sense by electrolysis or other chemical means, it means heat as much as you want locally and other fast operations as fuel (H2/O2) , it means here we go with space colonies and real estate material in a freezing hell world but which with technology and energy you can turn locally into whatever you like. It doesnt have to be that humans live there either in anything more than key heavily shielded positions below surface depending on AI developments. Radiation is bit of a problem at surface. "The radiation level at the surface of Europa is equivalent to a dose of about 5400 mSv (540 rem) per day,[40] an amount of radiation that would cause severe illness or death in human beings exposed for a single day"

All you need is a stream of automatic spaceships that carry all this precious cargo in a self sustainable energetically process to wherever you like in safer regions around Jupiter or on Mars, Venus even or other space colonies very far (it doesnt matter how far if you get an endless stream of round the clock ships many arriving every day etc) .

Now think in terms of energy requirements and the pace they are needed. It is much easier to take off material from Europa and Jupiter's gravity well at this distance into space destinations than from earth by many times over (the effective boost needed to take off from Europa near term is small - easier than the moon - so that ion propulsion gradually can take you out once in orbit). By that i mean that of course the escape velocity from this system (if you were to start fast) is still larger than earth even at this distance (say 100 times the earth radius but Jupiter has 318 times the mass of earth), however what matters when you have plenty of energy and are already in orbit around the main body is the near term boosting to access space and this is much easier from such smaller escape velocity satellite than earth itself at the beginning of it. After you are in space in orbit around Europa/Jupiter you can do other slower steady progress things to get to what you need in speeds to escape for good in a couple days or weeks. You can do that at your pace with ion propulsion (supported by on-board reactor fusion power), no need to do it in minutes real fast in huge rockets because g is locally significant and air resistance substantial like on earth. This is why taking off from the moon was so easy (no huge rockets and everything) compared to taking off from earth for eg the Apollo missions.

Also gravity at Europa is such that space elevators can be built there that are much easier to realize (in terms of available strength materials) than on earth. Once you are out of the satellite one way or another you can use ion propulsion to go in time to wherever you like if you have fusion for power and eventually much better net delta-v than chemical rockets, longer term acceleration methods can take you to huge speeds if needed over 100-200 km/sec (50-100 days to earth orbit and basically most inner solar system in months). The brief exit part to space in orbit around Jupiter is easier to get to with conventional boosting through Hydrogen/Oxygen or space elevators. Space elevators of course will facilitate the transfer of cargo to ships around Europa in a much more economic sense. Still however fusion is so lucrative that it can even justify chemical launch from the surface at 0.13g and no air resistance. Once in orbit you can load ships and start ion propulsion out of the system. This all sounds expensive (from today's pre-fusion perspective) but its not an issue if it is energetically favorable by a huge margin.

So an automated AI industry can exist that mines Europa icy crust at surface and even lower for water, H2/O2 and deuterium and other materials and then takes them wherever it's needed in the solar system in a few months time all financed by deuterium found in that water.

So you can use Europa for water and fusion and sacrifice some minor satellite out of the dozens there for other raw materials while in this system before leaving with all the materials (it will be even easier to mine and load to ships there than Europa). Then import all this to another location that doesnt have water but its much friendlier in other terms (closer to sun, warmer/ more light for solar power etc). Basically its less expensive and far less limited in terms of altering respected environments to carry water and other resources to these places this way than take it from earth, because local gravity well is harder at the beginning and the atmosphere is a problem until ion propulsion can take over. Also space elevators are harder in terms of materials needed on earth but much more feasible in satellites.

You use water itself for fuel (the fusion of its deuterium) to finance all this mega engineering process as the base of the economy. Eventually you can start extracting Deuterium directly from Jupiter's clouds that has endless supplies of Hydrogen and more Deuterium than any other place in this system but at much harder gravity, requiring far better spaceship technology not available for a while (very demanding so close to it). The point is Europa can be the starting point for all this eventually because it's much easier to begin this exponential expansion there. See how harder it is on Mars or Venus without water for any of this. Mars And Venus can go places with lots of Hydrogen provided (they have O2).

Do not think in terms of how hard this all looks now. Of course it does because we are not a machine based fusion economy yet with a stupid inept politics, selfish capitalist system and endless infighting factions that doesn't aim at high technology without someone profiting from it at the local expense of others. Of course it creates progress anyway (and is batter than other tried systems) but we can do so much better. The only obstacle is energy really and self sustainable high technology for automation because this is mega engineering requiring plenty of muscle power at the base (that cant be human anymore). If you can solve the energy problem with fusion of Deuterium (plus other fusion ideas may emerge too using other elements) found in water (say 1 part in 10000 or a bit more in general wherever you have Hydrogen) then the very fact you have access to plenty of water becomes the real game changer in these celestial bodies for all kinds of mining/extraction. The energy from fusion is more than enough per unit of mass to process the raw material and get more fuel for fusion many times over and then take it even out of the system to any distant destination.

You get basically 0.5%, call it 0.25% with efficiency issues, of mc^2 out of it via fusion. By contrast taking that mass out of the Jovian system after electrolysis and separation of D (that is the most expensive part of the processing of eg Deuterium, normal Hydrogen and O2 is the useful byproducts) and other chemical processes is many thousands of times less demanding than that. This is why all this extravagant idea can take place very cheaply with proper technology devoted to it that is obviously financed (ie it becomes important to others there so that they have incentive to start it) by deuterium trading to any destination of interest itself. The point is all that energy can more than cover the requirements to build all the technology many times over. This is why it becomes an exponential self sustainable process that ultimately can create a mega population of huge cargo ships. It doesnt even matter how fast these are (so we can make the process even cheaper i mean) if they operate in a clockwork fashion.

These places eventually have available energy that is thousands of times more than earth itself can offer in more accessible forms (less local gravity). This is why they can essentially finance the longer term redevelopment of the solar system into thousands of colonies of unimaginable diversity and technology. Think Elysium habitats thousands of times larger, looking inside like earth all created by machines and the energy sources suggested in many different locations of interest.

This is why water in significant size that has deuterium in typical 1 in 10k or 100k parts is a very important asset anywhere in the solar system. It can help you create anything elsewhere giving legitimacy to the excessively ambitious engineering. All this can alter eg Venus creating super worlds in its atmosphere for example if you import it there constantly in a permanent stream cycle of thousands of ships, hundreds arriving every day there in various points in orbit around Venus and then down to the atmosphere at thousands of processing sites. You do not even need to have space colonies for this idea. All you need is lots of water that is missing in Venus and you have a second earth and then some (many times over - huge atmosphere compared to earth). In the CO2 atmosphere of Venus you can build floating worlds at the altitude of ~50km (with gravity, temperature and solar radiation similar to earth there) many times larger than earth cities, provided you have the technology, energy and raw resources to do it. Basically what this world needs is Hydrogen, fusion, AI based technology and a few rare elements and the rest can be built there with organic chemistry from its atmosphere. Imagine light structures with outdoors pressure close to atmospheric, allowing access to outside areas with proper oxygen support (much friendlier than diving in the ocean in a suit). Indoors you will have normal atmospheric air in the floating structures because external CO2 is much heavier than normal air so big light weight organic compound structures with plenty of volume can float. Obviously you will have heavy equipment there in places too (like local industry) but overall the system will be floating if big enough. Most of buildings are empty space anyway. It will take some creative design too.

Basically all but Hydrogen is available there. Over time this infrastructure gives you access to the hostile surface below and you can do even more then locally using further resources/raw materials of this system not available in the atmosphere initially. On earth we develop in the ground and cant build in height as much. But in a floating world of many km effective altitude the volume you have access to is much larger than on top of earth's lithosphere (300m from ground typical modern skyscraper cities at best). You can build habitats over 5-10km of height and there is plenty of sunlight, C and O2, N2, S, Ar but limited Hydrogen for organic chemistry and water synthesis. Energy from deuterium and solar radiation (that requires materials like Si and better ideas by then to work of course) and Hydrogen and other elements imported is a game changer in the Venusian atmosphere. You can get a second earth economy started there.

With imported Hydrogen/Deuterium and other needed elements from other distant places (where you started the whole operation based on water) you can do all kinds of things in Venus by synthesizing again water (and getting the energy released by it too) using the Oxygen in CO2. You can finance this with solar energy there and the deuterium fusion for demanding tasks.

See, suddenly a few key hostile in general (cold/radiation) destinations in the solar system like the Jovian system with plenty of water/ice can turn other places (that are much friendlier but lack some essential details) to very interesting real estate and create a new economic human solar system AI supported empire in the process. Extravagant as this sounds it's nothing if there is an energy logic behind it, creating an exponential process that eventually reaches mega engineering levels. Machines will be doing all this not humans.

One may ask why bother even when we have so much on Earth. But because we need to get to the stars eventually. This is how it happens in steps. We need to make it less likely to go extinct and we need the innovation in technology and compact manufacturing all this demanding engineering will deliver. And because with proper extravagant usage of technology and energy we can indeed create worlds of amazing prosperity for billions of humans without taxing earth any further.

I hope they find water.

Not that exciting but first pictures from Juno of Jupiter and its moons.

nasas-jupiter-probe-sends-first-pics-of-planet-from-orbit

juno-makes-closest-jupiter-flyby Aug 27




NASA's Juno Probe Buzzes Jupiter in Its First (and Closest) Flyby


NASA's Juno spacecraft whizzed by Jupiter on Saturday (Aug. 27), successfully completing the first — and closest — of 36 orbital flybys planned for the duration of the probe's mission.

Juno arrived at Jupiter July 4 after a five-year journey, and this will be the closest approach of the entire mission, with the spacecraft grazing over the tops of Jupiter's clouds at a distance of just 2,600 miles (4,200 kilometers) at a speed of 130,000 mph (208,000 km/h).


During this encounter, Juno had every single one of its science instruments up and running for the first time in the mission. But it will be some time before most of the data and images from the flyby will be available to the public, researchers said.


"We are getting some intriguing early data returns as we speak," Scott Bolton, principal investigator of Juno from the Southwest Research Institute in San Antonio, said in a statement. "It will take days for all the science data collected during the flyby to be downlinked and even more to begin to comprehend what Juno and Jupiter are trying to tell us."

The first flyby data to be released will be high-resolution photographs from JunoCam, the spacecraft's visible-light camera. NASA will likely release those photos in the next couple of weeks. Images from JunoCam will offer the closest and most detailed views of Jupiter's atmosphere, NASA officials said.


"We are in an orbit nobody has ever been in before, and these images give us a whole new perspective on this gas-giant world," Bolton said.

Juno will continue to collect data on Jupiter's atmosphere, weather, magnetic fields and formation history until 2018. Then, the spacecraft is scheduled to plunge to its death into Jupiter's atmosphere, taking measurements all the while. But NASA says scientists will have enough data about Jupiter to study the gas giant for for years to come.

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