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> We're not going to have bits of data. We're going to have gigabits of data," said Philip Baldwin, acting director of the network services division at JPL. "I
by dmix 3y ago
> We're not going to have bits of data. We're going to have gigabits of data," said Philip Baldwin, acting director of the network services division at JPL. "I don't want 1080p for video resolution. I want 8K video."
Is this a reason why India's moon craft had such low resolution images? I checked and the rover only has 2x 1 megapixel cameras for some 3d stuff. The pictures from the lander were the usual low res generic stuff we've always gotten.
Why cant they put a 4k lense on these things? That has to have scientific value even for looking at their own rovers/landers for defects.
- squigaviator 3y agoThe problem with newer sensors and such is that they're not designed to handle the stress of going into space as well withstanding the greatly increased radiation exposure on Mars and the Moon. The missions to send stuff up into space is already expensive and so you'll have to reduce the chances of the gear you're sending up of failing. Unless you can afford to keep making trips to Mars until you get something there that works and then stays working long enough to do viable work.
- bozhark 3y agoThat seems so counter productive
- yencabulator 3y agoThe experimental helicopter on Mars might start to change the equation though -- it's built with many commercial grade components, instead of fancier things, and has worked well above expectations. The CPU is just a regular Snapdragon, like in phones. https://spectrum.ieee.org/nasa-designed-perseverance-helicopter-rover-fly-autonomously-mars https://spectrum.ieee.org/nasa-designed-perseverance-helicop...
- dr_orpheus 3y ago> Why cant they put a 4k lense on these things Bigger focal plane means more power, more data processing/storage means more power. More power means more solar arrays/batteries. More solar arrays/batteries means more mass. More mass means larger actuators to move it around. Larger actuators means more power...all of the above means more money. I can't give a specific reason why, but there are likely cascading effects and system impacts to the mission. Its not like larger space rated focal planes, larger data storage and high powered amplifiers to get more data down don't exist. But at some point you do just have to call it "good enough" or "meets requirements" to avoid the system spiraling out of control.
- Salgat 3y ago4K cameras are tiny, and you could only turn them on for a brief moment to take a picture.
- JoeAltmaier 3y agoIt's all about bandwidth. Pictures are nice but command and control are vital, so more bandwidth is given over to that. The bandwidth depends upon the power levels, antenna size, signal strength and the noise level. See the Shannon-Hartley theorem for details. This means from a small lander on the moon all the way back to earth the bandwidth is small. Sure put a big camera on there, but it'll take weeks to send one picture in its entirety. The Indian lander only has like 2 weeks of life total.
- croutonwagon 3y agoSure but I would assume they would eventually have some type of relay, like lunar gateway. Allow the landers to sip power and send to the relay, probably more a series of satellites in more eccentric orbits, and let those use their bigger solar panels and higher power to transmit/recieve back to ground stations. I mean, how would we communicate with Mars colonies when the earth and mars are at opposite sides of the sun without some series of satellites in a elliptical orbit possibly at angle perpendicular to our general orbital planes?
- pjc50 3y agoThe limit seems to be not the cameras, but the downlink.
- squigaviator 3y agoI think they're pushing for funding to upgrade the bandwidth. More channels, more data we can get at once.
- dmurray 3y agoYou can trade off resolution for time, though. Surely high resolution photos would be useful for some purposes, even if it means you only get a few of them in a day.
- GrinningFool 3y agoSeems like even that would come at the cost of other data that may be more critical (sensors, telemetry, etc).
- wolfram74 3y agoBut if the network is as a whole pushing full capacity, spreading out the load won't help because there's barely any slack to spread it into. You could get 4x resolution, but you'll only get 1/4th the amount of footage.
- dylan604 3y agoLet's face it, we don't really need 24fps+ footage from the moon. Nothing is changing on a timescale that would be interesting. Even if the cameras are on a rover, take high quality panoramic 360 stereoscopic images every time the rover moves to a new destination. During the course of the next move, it can be uploading that data. But who are we kidding? A group of internet forum nerds coming up with something that the people at NASA/JPL/ESA/etc haven't already considered?
- justin66 3y ago
- i-use-nixos-btw 3y agoI always wondered the same thing. But my theory wasn’t bandwidth, it was power, cost and (perhaps) weight. I had no idea that we still monitored these things from the ground.
- dmix 3y agoThe power/weight thing is largely solved thanks to cell phones. But they probably can't just buy it from industry, it has to be custom made for the project, with some gov-heavy regulation no doubt. But surely they could do far better than 1 megapixel.
- wongarsu 3y agoLots of space stuff is 10-20 years behind what we use on the ground because of radiation hardening. Both because volume is so low that radiation hardened electronics have a very slow update schedule, and because older technology is inherently more radiation tolerant (higher voltages, larger process nodes, etc). The ISS has off-the-shelf notebooks, but apart from that the uptake of regular non-hardened hardware is relatively recent and quite slow. I think the Falcon 9 has a couple non-hardened systems, and of course Ingenuity has lots of regular off-the-shelf hardware. That was one of the big reasons the predicted lifespan of Ingenuity was so low, but software mitigations (like the ability to reboot mid-flight) have proven very effective.
- dylan604 3y agoSo you take the miniaturization gains from cell phones, and then replace the size/weight by encasing it within a sphere of water to protect it.
- falcolas 3y agoYou'll need a ton (well, probably several tons) of water. https://space.stackexchange.com/questions/1336/what-thickness-depth-of-water-would-be-required-to-provide-radiation-shielding-i https://space.stackexchange.com/questions/1336/what-thicknes... ^^ Interesting read on this very topic.
- marsRoverDev 3y agoOur connectivity to mars is on the order of 12kbps, presumably better for the moon. My other question would be whether this is due to the need to radiation harden stuff? We were developing for what effectively was equivalent to an arduino in terms of processing power due to the need for radiation hardening (and other legacy / slow moving reasons).
- jsbisviewtiful 3y ago> whether this is due to the need to radiation harden stuff? It's been a very long time since I read about it so I cannot provide my source but yes that is likely part of it. There's also the resilience of the components to trauma to consider.
- dreamcompiler 3y agoOne of the key techniques for radiation hardening is big transistor geometries. Big transistors are less susceptiple to SEU (single event upset) caused by cosmic rays [0]. Unfortunately big transistors are old transistors. Modern 7 nm geometries are much too small to be rad-hard. Rad-hardness needs big 20-year-old geometries or even older. That also implies slower clock speeds. [0] https://en.m.wikipedia.org/wiki/Single-event_upset https://en.m.wikipedia.org/wiki/Single-event_upset
- JoeAltmaier 3y agoSurely redundant transistors would also be a useful technique. E.g. have an array of transistors at the current geometry, all doing the same function. The chance of a single event upsetting them all becomes unlikely.
- dotnet00 3y agoYes, the strategy IIRC SpaceX's Dragon uses is to have 3 more modern CPUs tied together, such that they're all running the same operation and checking each other. It mitigates errors without as much of a performance penalty.
- 3y ago
- kaliqt 3y agoThat doesn't make sense. Even if the speed is low right now, I don't see why you'd gimp the hardware. You can take higher res pictures and transfer them over longer periods of time.
- unnouinceput 3y agoWhile in the article said "8k video", I suspect he meant 8k live streaming. Which means right now or lose it forever. You can do hybrid if you want. Local cache on hardware that records on 8k, and streams live to 1k, so bandwidth is not exceeded.
- irrational 3y agoYou might run out of local disk space while waiting for whatever is there to transfer. Assuming you are continuing to take more pictures/videos and want to save them until they can be transferred.
- hutzlibu 3y agoI think disk space is cheap as well. Radiation hard electronics are not. And you don't have to send everything high quality. But at least some shiny pictures would be nice.
- anigbrowl 3y agoI don't buy that when you can buy 32gb of storage on a card the size of your pinkie nail for under $10.
- Arrath 3y agoSure but what does it cost for 32gb of space rated, radiation hardened memory? Maybe even in triplicate for a consensus system!
- dr_orpheus 3y agoI've got a quote in front of me right now for a ~1 TB data recorder for just shy of $4 million. Also keep in mind this isn't even for the highest class parts, this is more in line for something like a NASA Explorers program level [0]. Something you would get for a JWST or an Artemis level of program would be even more $$$ https://explorers.gsfc.nasa.gov/index.html https://explorers.gsfc.nasa.gov/index.html