I have a close friend that worked on the mars rover.
He uses me as a reference.
As soon as they start being like “can he use the latest android libraries and techniques” or some crap. I just shoot back:
“The man has code on another planet, he’s more than capable of picking up anything”
That would be a hilarious (and confusing) bumper sticker. When other parents say “my son is an honour student” you can smugly reply “yeah, but does he have code circling Jupiter?”
Congratulations, by the way. I’m being (trying to be) funny but I genuinely think that is cool and a reason to be proud.
I don't have code running on them, but I do have hardware designs aboard Pioneer 10 & 11. These were the first rocks we humans tossed high & fast enough from the Sun that they're never coming back. I'm a little proud of that.
Anybody with code circling Jupiter definitely has bragging rights and should be proud. If it were a just world, he/she wouldn't have to pay for a drink in a bar, ever.
These come from Juno, a mission sent in 2011 and orbiting Jupiter since 2016. Must say it wasn't really on my radar anymore, but looking at the timeline on Wikipedia, it's still going around and getting close ("perijove") every month and a week or so, at an ever-increasing longitude https://en.wikipedia.org/wiki/Juno_(spacecraft)#Timeline The planned end of the mission is in about a year. The camera was "included in the payload to facilitate education and public outreach [but] later re-purposed to study the dynamics of Jupiter's clouds"
Yeah, they had to fight so hard to get that camera on there! It was not included in the initial designs since it wasn't necessary for the science objectives.
Makes me wonder what it costs to send a "simple" camera along. Factors that make it probably not so simple: even 200 grams of camera (and extra solar panels to supply +10W while operating) probably costs many thousands of euros in rocket fuel and emission taxes. The engineering time to properly fixate it onto the spacecraft, integrate the software, and test the whole thing cost probably a few ten thousands in salaries. Radiation may be a big problem for what's otherwise off-the-shelf hardware, that might mean the hardware costs much more (tens of thousands instead of a couple hundred euros potentially?) and gets significantly heavier from shielding, but I wouldn't know how much. Is that about right, am I missing something major and/or am I off on orders of magnitude somewhere?
Yeah, you got a lot of it and the ripple effect of things that go out from it. In addition to the extra mass of the camera and solar arrays, there is extra mass for the harnessing to connect the camera to the computer and engineering design for that as well. Integration of anything else on the spacecraft will have to go through Failure Modes Effects and Criticality Analysis (FMECA). Basically, this gets in to pretty detailed circuit design analysis and makes sure that any failure on the camera itself (like a short circuit or babbling idiot data bus) won't impact the rest of the spacecraft.
Potential cost of increased storage onboard the spacecraft if it is significant data volume. Cost of downlinking the data to the ground, time on the DSN is expensive. I think the cost data sheets for DSN usage are online and it depends on data rate, what dish you are using, etc. but costs for usage are on the order of thousands per hour and data rates from Jupiter are pretty slow.
The cost of the camera itself is likely on the order of a couple hundred thousand. I've seen similar costs for small radiation hardened cameras and star trackers. The difference in parts cost for some things can be absolutely insane. Passive electrical components certainly cost more, but for active circuits it can be insane. A radiation hardened equivalent of a $20 FPGA can be something like $20,000.
All told, cost of integration and use over the mission is likely at least a few million. But on a $1.1 billion mission it still doesn't seem like a lot.
> A radiation hardened equivalent of a $20 FPGA can be something like $20,000
Has anyone actually tried putting up non-rad hardened equipment to measure how they perform? The Mars helicopter wasn't RAD hardened and used off the shelf parts & succeeded and the Mars atmosphere is not thick enough to meaningfully block the amount of cosmic rays hitting the surface.
I think NASA doesn't do a good job sometimes tolerating risk and then everything is treated as needing safety-levels of risk mitigation without considering that a 1/100th cost reduction will not generate as much in parts failures.
> I think NASA doesn't do a good job sometimes tolerating risk and then everything is treated as needing safety-levels of risk mitigation without considering that a 1/100th cost reduction will not generate as much in parts failures.
I do absolutely understand this impression of NASA. But I also think it gets inflated because the highest profile NASA missions that you hear about in the news are the most expensive and least risk tolerant missions. But there is pretty large spectrum in terms of cost caps and risk tolerance to NASA mission classes. I think generally in order of descending cost/risk tolernace it is: Human Spaceflight, Flagship (i.e. JWST, Mars Rovers), New Frontiers (Juno falls here), Discovery, Explorer, Mid-Explorer (MidEx), Small Explorer (SmEx), Venture.
For an example in the Venture class you can look at something like CYGNSS. Constellation of 8 spacecraft to better understand dynamics of hurricanes by looking at ocean wind speeds. This is done by mapping doppler delay of reflected GPS signals off of waves in the ocean. Important science, super cool technology with mostly automotive grade parts. ~$150 million for the whole mission that lasted about 7 years.
Yep, they do! I had some of this discussion on a thread talking about the Mars helicopter here that Goddard does a lot of radiation testing on commercial chips.
Lots of the new space, and smaller satellite companies use a lot of commercial parts. A lot of the flight data has shown even better results than the radiation testing (possibly due to added stress of testing at higher rates vs low rates over longer mission duration).
Generally speaking most of this is in LEO with a pretty low radiation environment. Whereas the area around Jupiter is one of the worst radiation environments in the solar system due to the radiation belts (like the Van Allen belts on steroids). This page on the Juno Radiation Vault says the spacecraft is exposed to an anticipated 20 Mrads of radiation. Whereas spacecraft in LEO are exposed to 0.1-10 krads per year depending on the orbit.
Also a fun fact, this is with Juno trying to limit exposure to the radiation belts as much as possible. [1]
Ok. That's a good point about the radiation belts. I hadn't considered that Jupiter's massive magnetosphere captures & concentrates a huge amount of solar energy & Juno is very close to it. Thanks for the additional info!
Lots of work on this in the High Energy Physics community. Big experiments can design their own rad hard silicon, but everyone else has to test. Lots of space rated electronics is also qualified at far lower levels than we need. Upside ia that people are happy to share what they find:
I guess we have grown used to this by now, but from the Moon landing pictures, to the Mars rovers and the various asteroid and planetary missions the objects of the Solar system are now vivid, complex and above all, "real" places.
I know what you mean - looking at planetary close-up images, I sometimes involuntarily get the feeling of what it would be like to be out there with the probe, lonely and desolate and millions of miles from home....
These kinds of images never fail to amaze me. I know there some editing going on to make them more visually accessible/impressive, but wow. Images are only going to get better, too.
It will be fascinating to see how the long running image of Jupiter, striated with a series of bands of distinct colour with a clear big "dot", will get replaced with more updated ones like this, chaotic, swirly, almost painterly in the ways the colours blend.
Beyond the appearance what always gets me is the scale. You see these beautiful swirls and then realize you could fit a planet in them. It’s mind boggling.
It's so scary! All those swirls are like planet size hurricanes. Had Jupiter been bigger, it would have been a star, and life on earth would not have existed. Gives me chills.
Also interesting to note that the combined mass of all planets in the solar system is only about 1.4 Jupiter masses (or 0.0014 Solar masses). The Sun did not leave us much to work with if we’re hoping to build a second star!
Earth's mass is something times 10^24. Jupiter's mass is 2 x 10^27. The smallest stars are 8 x 10^28.
On an exponential scale, Jupiter is closer to being a star than it is to being Earth. So... maybe you could say that Jupiter is almost a star. With such loose definitions talking about astronomical scales, there's a lot of room for interpretation and exaggeration.
I think the point is--in the spirit of appreciating Jupiter--Jupiter resembles the largest possible planets.
Anything that reminds me that we are living in an environment thin as an eggshell on a grain of sand surrounded by an infinite cold and deadly vacuum, punctuated by hellfires that would evaporate our hole planet if we got to close.
There are so preciously few places like Earth. How I wish more of us cared about it.
It doesn't care about us, and we don't need to "care" for it, it's going to be fine without us. What we don't do is care for ourselves, which is what you're really saying, self-preservation. The earth doesn't give two shits if it's 50 degrees warmer. You can't even say it's to protect life, because some forms of life will do way better in a warmer planet too. The universe / nature is gnarly already, much more than we can ever be, and plus, whatever we do, we're nature too. So in a way you're saying nature doesn't care for itself.
I can't help find such edgy cynism nothing else than juvenile. Yeah, sure, in the end nothing matters and the universe doesn't give a fuck about you.
And life on earth is just an accident, and that intelligence and consciousness exists here for a very brief time on the universe's path to heath death doesn't matter at all. Except of us poor conscious beings who find joy in being alive and actually have the capacity to marvel, because it is marvellous that we can, and we should.
And I care that it is us who inhabits the earth, and not slugs.
I thought my point flowed nicely from yours, sorry you didn't like it. For me it's about not having these visions of grandure about us as some protectors of the universe and instead accept our tiny place in all this. For example even your concept that our consciousness is more important than slugs or rocks, is all rationalization on your part to make your place in the universe have some meaning. Anyway, I don't then use this fun thought experiments to justify not recycling or denying human impacting climate change if that was what put you off.
> Had Jupiter been bigger, it would have been a star, and life on earth would not have existed.
Not sure a small star (e.g red-dwarf size) in Jupiter’s orbit would make much difference to Earth, other than it being brighter at night when it’s in the sky.
Jupiter's perihelion is only 5AU from the sun. I suspect that Jupiter could fall well short (mass-wise) of being a star, yet still be big enough to destabilize Earth's orbit.
Jupiters sphere of influence is full of radiation, meaning the sat needs a lot of shielding which makes it very heavy. Additionally, you need a lot of thrust to not only get to Jupiter, but to be able to get into a geosync orbit around a planet other than earth, so youre gonna need a lot of fuel. And finally, time... Europa Clipper just left earth, it will be 8 years before it arrives at jupiter. The windows for launch are long but very spread out, so mission timing would be important too.
And, funfacts time.. Clipper is going to europa but will be spending much of its time in orbit around jupiter, passing closely to europa every orbit. This was done to limit the amount of radiation the sat will get during its mission, and that orbit is uuuge, in order to avoid as much of the radiation as possible.
The area of Jupiter and its moons is probably one of the most hostile space environments in our system, catching asteroids, radiation, huge planet full of gasses that would corrode you and your ship if you dipped in, and a huge gravity well that makes it difficult to leave again once youre there. Not many other planets in our system are as dangerous as jupiter and friends.
I was under the impression that we now know how to do low-fuel paths through the solar system using gravity. It's more a question of how long do you want to take to get where you're going.
If you want to go faster, you need more fuel, and eventually you max out the biggest rocket available. Clipper is the most massive planetary probe ever-- they had to use falcon heavy in fully expendable mode to get it up there.
Yep, for reference Europa Clipper is 6,065 kg [0]. It is an absolutely massive interplanetary probe. It is getting close in size to some of the largest GEO communication satellites. And to get it out to Jupiter they definitely need some of the gravity assist trajectories.
On the opposite end of the spectrum, New Horizons was only 478 kg [1] and still holds the record for the fastest thing ever launched from Earth. It also did a gravity assist flyby around Jupiter and it still took 9 years to get to Pluto.
> New Horizons ... still holds the record for the fastest thing ever launched from Earth.
To expand on this a bit, it's the fastest launch. The unqualified speed record goes to the Parker Solar Probe in 2018, and was previous held by Helios B way back in 1976.
The distinction here is that New Horizons has spent it's life traveling away from the Sun, and it costs energy and thus speed to do so. Meanwhile, solar probes gain speed during their fall towards the Sun.
Yes, this specific specific duration has to do with the choice of launch vehicle. (No shade for any particular program as all have different tradeoffs and I'm gratified to see the probe successfully on its way.)
The SLS option would have entailed a direct trajectory to Jupiter taking less than three years. ... The move to Falcon Heavy saved an estimated US$2 billion in launch costs alone. NASA was not sure an SLS would be available for the mission since the Artemis program would use SLS rockets extensively, and the SLS's use of solid rocket boosters (SRBs) generates more vibrations in the payload than a launcher that does not use SRBs.
Not silly at all! There's actually a lot more being done here than just cropping...
> The image is reprojected according to a preliminary geometrical camera model, cleaned from some of the camera artifacts, approximately illumination adjusted with a 3rd degree polynomial BRDF over the cosines of the incidence and emission angle
Check out the "Source Image(s)" link attached to each pic, it should give you a much better idea what the camera is actually seeing. Scroll to the bottom of the source image and you can see the different color channels as well as how it's interleaved for transmission. Here's the example I pulled that description from and it's source:
Not a silly question. I don't think the images are actually cropped. JunoCam is described as a "push broom" imager [0]. The camera takes pictures as the spacecraft turns. So it's more like you are looking at a stitched together panorama and not a cropped version of a larger image.
If the variation of color are indicative of a similar variation in density, why is there so much turbulence in Jupiter, why are the upper layers not more consistent? Tidal motion? Anyone know?
In this post[1] there's a JunoCam picture from a previous flyby, which has been adjusted to be roughly as a human would see it. Still a lot of color though!
This[2] paper studies the ovals but has some details on the atmosphere, including the colors:
The reddish color is usually attributed to red “chromophores”, which are products of a series of complex chemical reactions, such as the UV photolization of ammonia with acetylene. These chromophores can act as coating material for the ammonia particles.
The cloud structure of the Jupiter's atmosphere, and in particular the nature of vortex features, as the [Great Red Spot] and the white ovals, is still puzzling.
This[3] paper tries to reproduce the reactions in the lab and compare them with the observed colors. It goes into some more details around the potential color formation.
I also want to just include this picture[4] because I just love the tiny fluffy clouds, which shadows provides amazing depth feeling.
[3]: https://doi.org/10.1016/j.icarus.2016.03.008Chromophores from photolyzed ammonia reacting with acetylene: Application to Jupiter’s Great Red Spot (use the hub of science for full paper)
It says exaggerated color/contrast. It seems to be a trend lately like the recent images of the Moon and Pluto. They might even be translating non-visible spectra to color so the material composition can be distinguished better, like they do with nebula and such.
It is well intentioned, it makes the images much more informative, and they are just really cool, which helps with public support. But it is also a bit misleading and confuses people.
Breathtaking! Just imagine, a century from now, maybe later or sooner, we could visit planets like Jupiter, that once, we could only look at them from the photo. I hope the humanity lives on, and strives forward in engineering.
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