Mars rover perseverance live stream - Page 1
Forum section: electronics / general

author: ali_asadzadeh
author_rank: Super Contributor
timestamp: February 25, 2021, 11:02:49 am
content: Hi,I want to know if is there any live video stream from the rover?do we have this luxury?

author: Gyro
author_rank: Super Contributor
timestamp: February 25, 2021, 11:10:22 am
content: I think the data rate is too slow. Nasa need to buffer it and then release occasional video clips. There must be lots of the available bandwidth that they are using for other'science'instrumentation related purposes too.

author: Psi
author_rank: Super Contributor
timestamp: February 25, 2021, 11:17:35 am
content: Nope.That would use way to much bandwidth.The rover can only communicate with earth at decent speed (max 250KBytes/s) for a short time per day when a mars comms satellite is overhead to relay it to earth, NASA use all of the time to send back still images and data.During other times the rover can communicate directly to earth if it needs but it's super slow, under 400 bytes per second.Livestreaming video from mars isn't going to happen until there is a communications satellite constellation around mars.I'd be surprised if SpaceX doesn't already have a plan to put some modified Starlinks sats around mars. They could be at a much higher altitude as latency wouldn't be an issue. Higher altitude would mean much less sats are needed to get coverage of the entire planet.My guess is they plan to do that as one of the early starship test missions to mars.

author: Gyro
author_rank: Super Contributor
timestamp: February 25, 2021, 11:29:40 am
content: Quote from: Psi on February 25, 2021, 11:17:35 amJust think of the backlash when the first inhabitants found that they couldn't get the internet.

author: nali
author_rank: Frequent Contributor
timestamp: February 25, 2021, 11:34:29 am
content: Quote from: Gyro on February 25, 2021, 11:29:40 amOr more likely the first inhabitants have decent streaming speeds whilst rural areas here still struggle with dialup speeds

author: ali_asadzadeh
author_rank: Super Contributor
timestamp: February 25, 2021, 12:42:43 pm
content: QuoteNice info, where did you get these communication Speed info? I thought it must be way more higher, because it's outer space and nothing is in it's way.

author: daqq
author_rank: Super Contributor
timestamp: February 25, 2021, 01:14:01 pm
content: QuoteKeep in mind the insane distances and limited power.

author: Psi
author_rank: Super Contributor
timestamp: February 25, 2021, 09:39:43 pm
content: Quote from: ali_asadzadeh on February 25, 2021, 12:42:43 pmFrom NASA perseverance page here.I summarized and converted from bits to bytes.https://mars.nasa.gov/mars2020/spacecraft/rover/communications/

author: Psi
author_rank: Super Contributor
timestamp: February 25, 2021, 09:49:17 pm
content: The main limiting factors for higher speed is- Limited size at the rover for having a huge dish or phased array antennas to send direct back to earth at high speed.- Limited speeds of the existing comms satellites that are already in orbit around mars.- Limited CPU speed on the rover. it's a radiation hardened CPU and doesn't run super fast, around 200mhz. So it's not going to be realtime encoding 1080p in h264Best option for improving speeds in the future is bigger/better sats around mars and a phased array antenna, similar to starlink, on the rover.

author: ajb
author_rank: Super Contributor
timestamp: February 26, 2021, 03:16:23 am
content: Quote from: Psi on February 25, 2021, 09:49:17 pmOne of the interesting tidbits about the mission is that the little flying drone, being a technology demonstration mission, has much higher tolerance for failure than the primary rover mission and also has to run some pretty fast control loops what with having to be an autonomous rotorcraft and on a planet with different gravity and atmospheric conditions than here on earth. So they're using a standard mobile SoC, a Snapdragon 801, which has VASTLY more raw processing power than the entire rest of the mission hardware combined. It also sports a rangefinding part purchased off-the-shelf from Sparkfunhttps://www.fierceelectronics.com/electronics/drone-helicopter-to-land-mars-attached-to-belly-perseverance-rover

author: floobydust
author_rank: Super Contributor
timestamp: February 26, 2021, 06:49:49 am
content: Computing power aside, I can't see a BGA-packaged part in the drone surviving the temperature swings of Mars

author: SiliconWizard
author_rank: Super Contributor
timestamp: February 26, 2021, 11:45:01 pm
content: Beyond the technical limitations... let's assume for a moment it was at all possible to do a live stream from Mars. I doubt the NASA would let that stream publicly for all to see, unattended...There may be some critical stuff done during the mission that they don't want people to see, at least not in "real time" and before they would have processed the images as they see fit. There may be occasional mishaps (there always is!) that they wouldn't want the public to see either. Imagine how quickly things escalate on social media these days. That could literally ruin NASA's efforts and the public opinion. There may also be discoveries that they don't want to unveil immediately, etc.That's just not going to happen even if some day that became actually feasible. Or they would control the streaming and would let it happen only under strict supervision and for limited amounts of time.The day we have free live streams from cameras on Mars - it probably will be when we have already colonized it. If it ever happens, and if there are people left on Earth after that.

author: T3sl4co1l
author_rank: Super Contributor
timestamp: February 27, 2021, 12:05:03 am
content: Eh, I doubt they would worry about it. Astronauts can hardly take a piss without mission control having planned it out beforehand.Streaming video of a preprogrammed autonomous vehicle is about as close to "Reality TV" (read: scripted and/or heavily edited pseudo-organic drama) as it can get, eh? Honestly, if something unexpected "slips" out in such a case, I'd think they'd be thrilled; it's an opportunity to spin it into real drama (a problem in need of a solution), or it's an opportunity to show the scientific process, a teachable moment (sometimes unexpected things happen; sometimes tools break, sometimes you discover aliens, you know, whatever). Any producer would be thrilled to have their own microcosm of Apollo 13 (the movie), right?Mostly though, it'd just be supremely boring... these are not powerful vehicles, travel is almost as fast as paint drying. I mean, they can still give a schedule for expected highlights ("drill arm will be active tonight at X, check it out"..), and there'll always be a few people watching any time day or night, and sometimes they'll spot something odd and get some Internet Points from it.Heck, maybe in say the next decade, we'll be far enough along that this sort of thing is actually feasible, who knows. Or if not on Mars, then on the Moon surely, or when they get down to mining asteroids perhaps...Tim

author: MikeK
author_rank: Super Contributor
timestamp: February 27, 2021, 01:11:52 am
content: I remember seeing live stream of some shuttle missions - perhaps they were ones of Hubble repair. They were boring as hell. I don't know why many things need to be live streamed.

author: Brumby
author_rank: Unknown
timestamp: February 27, 2021, 02:19:09 am
content: Quote from: MikeK on February 27, 2021, 01:11:52 amBecause they are new, interest will be high - and that's when you want to service the demand in order to maximise public engagement.The trouble is things get boring very quickly when you deliver the same sort of material over and over. Take the movie Apollo 13 for example. There is a scene before the explosion where the crew were doing a "live stream" and the TV channels were not running it. Al that changed when the disaster happened, but until that point, it was rather hum-drum.As mentioned (several times) above, the bandwith/distance/power elements make this a major challenge which is impractical - but even were we to develop such capability, the video stream is going to be very boring to the vast majority of viewers - very quickly. Imagine a commentator saying, "Let's pan right to get a closer look at that rock - and then you have to wait half an hour (depending on Earth/Mars separation) to see that happen. You ask for it now - but realities like this would sour your interest in very short order.I am much more in favour of the experts managing the raw data and presenting a far more concise and meaningful piece of media that delivers the level of information we expect in a time frame we are used to.