Juno successfully enters orbit around Jupiter

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Juno successfully entered orbit around Jupiter this evening.

NASA will shortly have a press conference with more details about the spacecraft’s status.


  • wayne

    >During the live presser, after opening statements, they did show some short video that was taken 5 days ago, before they turned off all the instruments. Shows the moons orbiting. >Very cool.

  • Alex

    Congratulations! That kind of robotic interplanetary missions belongs to best things what USA delivers to world. I would like to see also an Uranus orbiter in next decade to deliver insight in composition and internal structrue of Uranus, which is a ice giant. Why not build another copy of Juno spacecraft, which is slightly modified?

  • Alex

    Oh, I am sorry and I am “stupid”. Clearly, missions beyond Jupiter’s realm need RTG as power supply. Therefore required modifications of Juno S/C as an Uranus orbiter are somewhat larger as thought.

  • LocalFluff

    I’m surpised they shut down the instruments. Even a failed orbital insertion could have a given great flyby measurment of the magnetic field. Failed orbital insertions are not uncommon in Earth orbit, at Mars and at Venus.

  • wayne

    Juno’s Approach to Jupiter

  • wodun

    Why not build another copy of Juno spacecraft, which is slightly modified?

    Why not build different classes of satellites in large production runs and have constellations over every planet, certain moons, and asteroids?

    Every satellite is always a one off, maybe with a backup in case the first suffers a launch failure.

    Standardization will impact specialities but in the long run, it would be worth it.

  • Localfloff

    Uranus is probably the next big robotic mission for NASA. It should be (as long as they keep ignoring Venus, the obvious target). But more than ten years from now, I think that the distance makes it hard to organize people to do this. Imagine building your career on something which might happen late next decade, unless something goes bad on the way.

    Why do they not mass manufacture space probes?
    Because physics is about pushing the limit. You always need the most recent invention to try to capture the most exotic thing, or unthing. Those who go into physics are not very interested in teaching latin the same way as it was thought thousands of years ago. They want to find something new. New. As in infrared mirrors made out of beryllium cooled by helium and put in some abstract Lagrange orbit around nothing far far away. That kind of stuff. Catching every photon is not enough for todays brilliant students, they think of gadgets greater than the cubic kilometer neutrino observatory in the Antarctic, than the accelerator in Geneva, than the very large baseline interferometer with its radio telescope out to a lunar distance, than the planned space laser interferometer. Something even greater. Another Hubble would be boring. Need something new. It is all about motivation. Why take another step if it was not interesting?

    They did use to make them in pairs, like Voyager and Pioneer and Viking. And the MSL rover has its twin going to Mars in a few years, we hope. The marginal cost for a doublette should be low. But I think they did it back then because stuff were blown up or crashed down during the crazy space race. Not at all as often as they feared, at least on the right side of the iron curtain. But now one can actually count on stuff working, and they really do, so the economics has changed. Quantity has lost its value, you gotta be unique, the best ever.

    The mad astronomologist, wearing his wizard hat, cries:
    – Magic mirror mirror in the sky, tell me what is furthest away!

    And the black emptyness answeres in its mathematical hieroglyphs:
    – The first of things and nothings are what are the furthest away. Of all.

  • Alex

    Localfloff: Yes, Venus and Uranus are very important scientific targets (and somewhat “forgotten”) to understand not only our own solar system ‘s (incl. Earth’s) creation, but also for understanding and modeling exoplanets. Jupiter stands for the category gas giants, Uranus for ice giants and Earth/Venus for rocky planets, whereas in last case it is important to understand what made Venus to “hell” and Earth to “paradise”, despite its similarity in size, mass, position and composition. Also very important for exoplanet science.
    Why not use an armada of very small, cheap space probes (may be even cubesat type), arranged in a huge network, where the loss of some is not important and information is transferred from one to the other?

  • Edward

    Venus is not exactly ignored. The Japanese have a satellite there as we read and write. The US sent a few satellites there, and the Soviets even took a photo of the surface, before their lander gave out. (The pressure and the heat at the surface makes it a big deal that their lander survived long enough to get a photo.)

    Another reason for duplicates of Pioneer and Voyager were that they were fly-by missions (similar to New Horizons at Pluto and any other object it is directed to study), obtaining only a little information in the short time that they were near their target planets. Unlike modern orbiters, they would not stay with their target planets long enough to get much information, but they were able to get enough to make the following probes more profitable. Each early probe discovered new information that helped scientists figure out what they wanted to concentrate on for future missions. Probes such as these taught us a great deal about space navigation within the solar system and about making reliable hardware for the journey and the science missions.

    “Because physics is about pushing the limit.”
    It is not worth the cost and effort if all you are going to get is the same information, time after time. An advantage to creating a constellation of satellites around another planet is to get planetary coverage, information about what is happening all over the planet at the same time (which is really just a global weather report, but that could help us develop reliable weather and climate models).

    When Mariner 9 reached Mars, we learned a lot about the planet, relative to what had been known up to then. Later satellites had better cameras and different instruments, and we learned even more. Various landers and rovers have given us even more information about Mars.

    Cubesats and small satellites can give us additional simultaneous coverage, but their size limits the number, size, and capabilities of their instruments. All these things need to be considered when planning a space mission. The following link may give an idea of how a mission is planned and executed (if you are interested in the subject, I recommend taking the time, over the next few weeks, to read the whole “primer”):

    “Another Hubble would be boring.”

    It is less about excitement and more about getting our money’s worth. If it is a choice between building another Hubble and going to Uranus or Venus, the decision makers/financiers want to know which will give the better* new information. Budgets are for a reason (if you don’t have them, then a country could easily spend tens of trillions of dollars more than it has, borrowing more than it can repay), so there is only a limited amount from which all missions, present and future, can be funded.

    * The word “better” can have a fuzzy meaning. It may mean discovering the origin of life, the origin of the solar system, or the origin of the universe. Different scientists, foundations, and government agencies may have different ideas as to what new information is “better.”

  • Localfluff

    Exoplanets give a context to Solar system exploration which I think makes atmospheres more important to investigate. All planets have atmospheres, except for the smallest one. And exoplanetary atmospheres can be observed at other stars. And they are pretty complicated systems, climate science hasn’t exactly been very successful with its forecasts even on Earth.

    Duplicates are rivaled by rovers. Opportunity going to a new place is about as good as a new stationary lander, or even better because the rover has a context of exploration. I think balloons can become a big thing in planetary exploration, Soviet/ESA used balloons at Venus in the 1980s, and all the outer planets and Titan are like made for it. It won’t work at Mars, but I think that future probes somehow must swim around in atmospheres. Planting a flag and leaving a foot print is romantic and local, but most planets don’t have solid surfaces.

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