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Perseverance Rover lands on Mars [video]

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Re: Perseverance Rover lands on Mars [video]

#281

Post by chasd00 »

WJW wrote: post #39
shadowgovt wrote: post #36

Earlier quoted context omitted.

Upright and in one piece. :) No, but seriously: amazing engineering and amazing work. So great to see the images streaming in already.

The skycrane system is just SO COOL. It's also one of those things that is super easy to explain but incredibly difficult to actually construct, let alone have it work well after flying all the way to Mars.

i can't believe it works. Those thrusters making all that turbulence and racket. Then the cables have to unwind without getting tangled and at the same rate. Then, finally, at the end, they have to detach the cables and fly away. It's pretty nuts.

Re: Perseverance Rover lands on Mars [video]

#282

Post by Nzen »

koheripbal wrote: post #165
tectonic wrote: post #14

You can also watch an EDL visualization in your browser: https://eyes.nasa.gov/apps/mars2020/#/home And read about how it will use Terrain Relative Navigation to find a safe landing spot: https://www.jpl.nasa.gov/news/a-neil-armstrong-for-mars-land... Perseverance is phenomenally complex, its Sample Caching System alone contains 3,000+ parts and two robotic arms. So exited for all the sciencing this nuclear-powered,…

Any idea when they will start experimentation? I want to find microbial life!

I don't know in general, but JPL published a video [0] yesterday of three interviews. One of the systems engineers for the MOXIE (atmospheric oxygen separation) unit will wait several weeks after landing before their first experiment. Actually, scientific american has published a timeline that seems to corroborate that [1].

[0] https://youtu.be/TUd604rBR6I?t=643

[1] https://www.scientificamerican.com/article/the-first-100-day...

Re: Perseverance Rover lands on Mars [video]

#284

Post by ape4 »

interestica wrote: post #241
huhtenberg wrote: post #32

First surface photo is in too! https://i.imgur.com/C2s1job.jpg

NASA is making the raw images of everything available: https://mars.nasa.gov/mars2020/multimedia/raw-images/

Today's images are from Sol 0. Zero-based counting rules.

Re: Perseverance Rover lands on Mars [video]

#285

Post by garden_hermit »

spullara wrote: post #132
garden_hermit wrote: post #44

Watching these is always a stressful experience, I can't imagine what it would be like sitting in that room, praying that the object you spend years of work on is able to land by itself 7 light-minutes away. I'm looking forward to what Perseverance will teach us.

Right now it is 11 minutes away!

I was still under the assumption of Curiosity's 7 minutes! Thanks for letting me know

Re: Perseverance Rover lands on Mars [video]

#286

Post by m4rtink »

Sharlin wrote: post #171
unanswered wrote: post #167

Something I don't understand: when they say "X is 1 minute from happening", does that mean it's really 1 minute from happening or does that mean "in 1 minute we'll receive the signal that X has happened"? Maybe my question makes more sense in the case of "X is happening right now", because then I should either understand "we infer that X should have happened right about now" or "we have confirmed via signal that X ha…

Yes, those are all Earth Receive Time, that is, when they were saying that eg. entry interface is two minutes away, in reality the rover was already sitting on the surface and we were just waiting for the radio signal to get here.

The local Czech stream (20k viewers!) I watched went over the events in real time and then commented how events were happening as signals were received on Earth - with the final confirmation of successful landing coming first via Twitter, no less! :)

Still a very nice yet nerve wrecking idea to do it like this - you know the lander is on Mars now. But is it safely on the ground or is there a third Shapirelli crater now ? You don't know! A huge relief in the end. :)

Re: Perseverance Rover lands on Mars [video]

#287

Post by electriclove »

mu_killnine wrote: post #31

The Nasa person they have helping narrate what's going on is so genuinely happy the landing went well. It made me kinda tear up. It's infectious just how excited all these people are about this project. Also, I was a bit worried he was going to pass out. 10/10, would watch again (and probably will with my kids)

This guy? https://www.youtube.com/watch?v=gm0b_ijaYMQ&t=1h41m36s

That is Rob Manning, an absolute legend! Here is an interview with him from a few years back: https://solarsystem.nasa.gov/people/2280/rob-manning/

He also wrote this great book: https://www.amazon.com/Mars-Rover-Curiosity-Curiositys-Engin...

Re: Perseverance Rover lands on Mars [video]

#289

Post by m4rtink »

whuffman wrote: post #179
handedness wrote: post #103

Earlier quoted context omitted.

The world is a complicated place, Hobbes.[1] The lower "HazCams" hazard avoidance cameras (which captured those initial photos) are there to detect hazards (rocks, trenches, etc.). They are stereoscopic, lightweight, and high resolution. My guess is that using color sensors would have either increased the 3D mapping precision or added weight/power/bandwidth requirements, or otherwise been less robust in that environm…

FYI - the HazCams on Perseverance are in fact in color (this is new, they were black and white on Curiosity)! Stereo precision was a concern based on the switch to color sensors, so there was some algorithmic work done to make sure it wouldn't cause an issue. (Source: https://link.springer.com/article/10.1007/s11214-020-00765-9 - "The Mars 2020 Navcams and Hazcams offer three primary improvements over MER and MSL. Th…

Wow, real upgrades all around compared to Curiosity!

What are they going to do next ? Put on board a solar powered Mars helicopter ?? ;-)

Re: Perseverance Rover lands on Mars [video]

#290

Post by m4rtink »

zokier wrote: post #261
kibwen wrote: post #145

Earlier quoted context omitted.

Here's a page with data about the Deep Space Network: https://mars.nasa.gov/msl/mission/communications/#data "The data rate direct-to-Earth [from Mars] varies from about 500 bits per second to 32,000 bits per second"

Clarification, that is for the old Curiosity rover. The page for Perseverance has some additional information > 160/500 bits per second or faster to/from the Deep Space Network's 112-foot-diameter (34-meter-diameter) antennas or at 800/3000 bits per second or faster to/from the Deep Space Network's 230-foot-diameter (70 meter-diameter) for high-gain antenna, and > Approximately 10 bits per second or faster from the D…

Maybe it was the low gain antenna but via MRO or other orbiter? 30 bits per second seems like a bit too slow to get even the two small images back so quickly.
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