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Perseverance rover’s descent and touchdown on Mars [video]

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Re: Perseverance rover’s descent and touchdown on Mars [video]

#51

Post by ckosidows »

spookthesunset wrote: post #31

As it got closer to the ground, it seemed really hard to get a sense of scale with that downward camera. It felt like the ground just kind of "appeared" right before the sky crane did its thing. How big are the rocks under it? It felt like they were either big (1+ meter) or just little pebbles. I really couldn't tell. Either way, this is seriously the coolest video I think I've ever seen. I cannot wait for more.

Agreed with both. I hope someone can eventually put an estimated 3D model of something familiar, like a person or a school bus or something, for scale in the image video.

And this is one of the coolest videos I've ever seen. I had a huge smile watching all of it. I can't even fathom how elated the whole JPL team must have been as these videos came in.

Re: Perseverance rover’s descent and touchdown on Mars [video]

#52

Post by djxfade »

krm01 wrote: post #29
O5vYtytb wrote: post #5

I don't know why I'm surprised at the amount of footage and the quality, but I am. This is really setting a new bar for missions like this, similar to what SpaceX has done in recent years. Stuff like this has got to be huge for getting interest and excitement from the general public and especially kids.

It would be great to see some startups work on interplanetary video streaming tech. If you're building an other video streaming service, stop what your doing, and give this a try. I know I know. Very, very hard to solve and all, and this is totally a fanboy speaking, but it would have been awesome if we could have seen this footage in (as close as possible to) real-time when the landing happened.

So, the minimum delay between Mars and Earth is around 11 minutes, usually higher. And the bandwidth is something like 60 MiB/Sol. This is just totally unrealistic with any known tech for the foreseeable future

Re: Perseverance rover’s descent and touchdown on Mars [video]

#53

Post by joeyh »

This was recorded by a computer running Linux, using ffmpeg. Embedded Intel system with fairly stock cameras.

"the first open source linux box running on the surface of Mars"

"thank you to the open source community for allowing us to use your amazing software"

Per their press conference today, in the Q&A section. https://youtu.be/gYQwuYZbA6o?t=4025

Re: Perseverance rover’s descent and touchdown on Mars [video]

#54

Post by Trasmatta »

spookthesunset wrote: post #31

As it got closer to the ground, it seemed really hard to get a sense of scale with that downward camera. It felt like the ground just kind of "appeared" right before the sky crane did its thing. How big are the rocks under it? It felt like they were either big (1+ meter) or just little pebbles. I really couldn't tell. Either way, this is seriously the coolest video I think I've ever seen. I cannot wait for more.

At about 2:57 the operator says the rover is about 20 meters off the surface, if that helps at all. I agree it got really hard to get a sense of the scale once the thrusters started blowing up dust.

Re: Perseverance rover’s descent and touchdown on Mars [video]

#55

Post by jandrese »

wycy wrote: post #39
aosaigh wrote: post #15

In case the other thread doesn't make the front page, they also added a microphone to this lander and managed to capture the sound of Mar's wind, which to me is almost more amazing: https://soundcloud.com/nasa/first-sounds-from-mars-filters-o...

Pretty cool, although it's so hard to really get a sense of sound of wind with a microphone. I guess the takeaway is that Mars is super quiet.

1% atmospheric pressure would do that. Sound won't travel very well through the Martian atmosphere.

Re: Perseverance rover’s descent and touchdown on Mars [video]

#56

Post by wycy »

jandrese wrote: post #55
wycy wrote: post #39

Earlier quoted context omitted.

Pretty cool, although it's so hard to really get a sense of sound of wind with a microphone. I guess the takeaway is that Mars is super quiet.

1% atmospheric pressure would do that. Sound won't travel very well through the Martian atmosphere.

Wow, very interesting. I had a pre-conceived notion that Martian atmospheric pressure was something like 20% of ours, but you're right, it's quite a bit lower than even that.

Re: Perseverance rover’s descent and touchdown on Mars [video]

#57

Post by tppiotrowski »

Can someone comment on why this is the first time I'm seeing videos from Mars versus previous missions.

Did the memory write speeds increase, more sensitive CCD sensors, easier to send data back to Earth?

I'm sure there must be some technological reason this wasn't done before because it's simply stunning...

Re: Perseverance rover’s descent and touchdown on Mars [video]

#58

Post by yazaddaruvala »

udev wrote: post #24

There is this emotion, not sure it has a name, which I am sure many engineers know -- when you prepare your system for a long time and then send it into the real world and watch it work... You can feel it in this video, e.g when you see the crane fly away after accomplishing the mission. If we don't have a name for this emotion yet, I hope the japanese or the germans invent one. :)

I think its similar enough to "closure" to re-use that word.

Re: Perseverance rover’s descent and touchdown on Mars [video]

#59

Post by giantrobot »

krm01 wrote: post #29
O5vYtytb wrote: post #5

I don't know why I'm surprised at the amount of footage and the quality, but I am. This is really setting a new bar for missions like this, similar to what SpaceX has done in recent years. Stuff like this has got to be huge for getting interest and excitement from the general public and especially kids.

It would be great to see some startups work on interplanetary video streaming tech. If you're building an other video streaming service, stop what your doing, and give this a try. I know I know. Very, very hard to solve and all, and this is totally a fanboy speaking, but it would have been awesome if we could have seen this footage in (as close as possible to) real-time when the landing happened.

Nothing about "interplanetary streaming" needs to be invented. The limiting factor is the size and power of the transmitter on Mars (or wherever). The MRO orbiter for instance is the highest bandwidth probe we've sent to Mars and it maxes out at about 4Mbps when Mars is closest to Earth. When Mars is farther it can only do about 500Kbps. That relatively prodigious rate requires the use of 34m receiving antennas on Earth.

So if you wanted to stream video from a GoPro on a Mars orbiter you could do so with current technology, you'd just need to build some big-ass antennas on Earth and then build and launch the Mars orbiters. Besides being technically difficult (because rocket science) it would be really expensive.

Re: Perseverance rover’s descent and touchdown on Mars [video]

#60

Post by ctdonath »

udev wrote: post #24

There is this emotion, not sure it has a name, which I am sure many engineers know -- when you prepare your system for a long time and then send it into the real world and watch it work... You can feel it in this video, e.g when you see the crane fly away after accomplishing the mission. If we don't have a name for this emotion yet, I hope the japanese or the germans invent one. :)

“It worked! On to the next task...”
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