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Old 9th March 2021, 11:06 AM   #201
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Rather timely given this thread.

https://www.wired.com/story/we-shoul...opes-in-space/

NASA looking into building large telescopes in orbit.
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Old 9th March 2021, 11:47 AM   #202
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Originally Posted by Myriad View Post
All that is clearly talking about the limits of what is achievable within the overall envelope of a single launch vehicle and the already-designed mission framework that fits within that envelope. That's why they're talking about things like optimizing the timing and navigational precision, rather than building anything besides the lander any bigger.

They're saying, you can't add fifty more passenger seats (or even 2 more) in a Honda Odyssey, no matter how much you redesign the interior to eliminate unneeded ashtray space. Fine, no argument there. But that doesn't mean designing and building a bus is impossible. Not if we can put modules together in Earth orbit, which we obviously can if they're designed as modules to begin with, and have done since the Gemini program.
This is wrong. They are clearly talking about the limits of using a sky-crane EDL system to land an object on Mars. They actually state this

"2.4 Mass Delivery Capabilities of the MSL-Derived Sky Crane"

"the delivery mass capability is estimated to be 1,050 kg"

What this means is that ANY system derived from the sky-crane EDL, no matter how big and powerful you make it, has a limit to how much mass can be landed on the surface of Mars and that limit is about 1100 kg using currently available materials and technology. It does not matter whether you use a single launch vehicle or 10 launch vehicles and make the sky-crane 10 times bigger and more powerful - 1100 kg is about the limit, and the factors affecting that limit are mainly the thickness and density of the atmosphere, and the minimum possible velocity at atmosphere interface. Its the same reason why a micrometeor big enough to survive atmospheric entry intact lands relatively gently on the surface on the earth, but a ten ton meteor smashes into the earths surface - because the Earth's atmospheric thickness and density is sufficient to slow down the former but not the latter.

Do you understand why they went to using Sky-crane in the first place? Its because the MSL rover was too heavy to use the previous EDL system, airbags and lithobraking. Spirit and Opportunity (each weighing about 180 kg) were encased in air bags, then landed by bouncing on the surface and rolling to a stop to dissipate impact. But that approach wouldn’t work for Curiosity, which weighs five times more than Spirit or Opportunity.

In engineering, whether it be aeronautical (my field) or aerospace, every system has its limits. Sometimes, those limits are due to engineering principles such as the square-cube law and Tsiolkovsky's rocket equation, sometimes they are due to the limits of materials science, sometimes they are imposed by environmental considerations, and sometimes by combinations of the aforementioned.
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Old 9th March 2021, 11:48 AM   #203
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Originally Posted by smartcooky View Post
That either means your initial rocket has to be bigger, or you will need a third launch to bring that extra fuel into orbit.
Isn't Starship supposed to get refueled six times in orbit?

Think of it as a slightly more elaborate form of staging.

I'm working from two premises:

1. The goal is more science.

2. A larger mass of payload enables more science.

We both want to increase the science payload mass significantly. You want to do so by adding humans to the payload, along with their added mass of consumables and safety margins.

Your argument about mass limits from the Earth's surface is entirely spurious. Your own vision requires numerous additional launches per mission. And all current proposals envision some sort of orbital assembly or refueling process.

So we can dispense with that objection right now.

What's left is deciding what's the best use of our increased payload mass. Humans? Or robots? As far as I can tell, the main argument for humans is an appeal to emotion.
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Old 9th March 2021, 12:29 PM   #204
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Originally Posted by theprestige View Post
Isn't Starship supposed to get refueled six times in orbit?

Think of it as a slightly more elaborate form of staging.

I'm working from two premises:

1. The goal is more science.

2. A larger mass of payload enables more science.

If you want to do more science, why would you build one big rover that can only go to one place rather than multiple rovers that go to multiple places.. for the same or a cheaper price! Seems like your premise defeats its own purpose

Originally Posted by theprestige View Post
We both want to increase the science payload mass significantly. You want to do so by adding humans to the payload, along with their added mass of consumables and safety margins.

Your argument about mass limits from the Earth's surface is entirely spurious. Your own vision requires numerous additional launches per mission. And all current proposals envision some sort of orbital assembly or refueling process.

So we can dispense with that objection right now.

What's left is deciding what's the best use of our increased payload mass. Humans? Or robots? As far as I can tell, the main argument for humans is an appeal to emotion.
Then you are telling wrong.

Even taking into account that humans require additional support materials, they can still do vastly more than our current robotic exploreres will ever be able to do. Until we are capable of building robots along the lines of Asimov's fictional AI, free thinking robots, capable of totally autonomous functioning (which I seriously doubt we will be able to do, at least in the foreseeable future) this will always be the case.

As I said earlier, our current robot explorer technology has to be controlled and driven, programmed what to do and what to look at. When Harrison Schmidt discovered the famous "orange soil" on the moon, that was because he saw something interesting, it caught his eye, and he went to investigate. That discovery changed our understanding of the formation of the solar system... it never would have been discovered by a robot unless it had been specifically programmed to look for that, and that is the problem with robots - they can only do what they are programmed to do - they don't have decision making capability or intuition - they cant look behind things or look around and see something that is interesting and decide to to go over and have a look.

At our current level of robotic technology, humans will always be able to do far more science than robots can do, and will always be able to do it far more quickly. It will take a colossal advance in robotics before this will change.
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Old 9th March 2021, 12:57 PM   #205
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Originally Posted by smartcooky View Post
This is wrong. They are clearly talking about the limits of using a sky-crane EDL system to land an object on Mars. They actually state this

"2.4 Mass Delivery Capabilities of the MSL-Derived Sky Crane"

"the delivery mass capability is estimated to be 1,050 kg"

I don't think they're clearly stating that at all. What do you think the phrase "MSL-Derived" means in the quoted title? It's a rather important qualifier. Comparable to what "Honda Odyssey-derived" would mean in my earlier analogy. I think if they actually meant "Mass Delivery Capabilities to Mars' Surface of Any Feasible Sky Crane" they'd have said something more like that.
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Old 9th March 2021, 01:15 PM   #206
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Anyhow, the discussion at this point has gone way past the skycrane issue, which came up in the context of "rovers are so limited and it's impossible to even land a less limited one that would be heavier," as if landing manned craft and facilities would be any easier.

As we all seem to agree, even if the mass of Perseverance were some kind of fundamental limitation on the mass of a surface landing, there's no reason more of them couldn't be landed. Rovers could be landed near stationary sample-testing instruments. If multiple rovers were landed close together along with stationary base station(s), some of them could be equipped with in situ experiments like Perseverance is, while others were specialized for collection and delivery of samples to the stationary lab(s).

There's a time delay, but wouldn't humans watch the feeds and still be able to notice some funny colored soil along the way? Then instruct the robots to go back and check it out?
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Old 9th March 2021, 02:35 PM   #207
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Futher to my most recent post, lets compare like with like, the robotic Surveyor Program v the manned Apollo program. Its a fair comparison because both programs were

1. Contemporaneous

2. Carried out by the same organisation

3. Similar in the technology they used for launch and landing

4. Sent to the same destination.. the Moon

5. Subject to the similar budget authorizations and constraints

The Surveyor program cost $599 million in 1973 dollars. It launched seven robot landers to the Moon, two of which failed, leaving five successes (that's $120m per successful lander). Each Surveyor carried a camera and a soil scraper. The science it did (outside of its own rocket science such as proving it was possible to do what it did) was pretty much limited to taking a few photographs and scraping up some lunar soil in order to study soil mechanics.

The Apollo Program cost $25.4 billion in 1973 dollars. It launched 27 humans to the Moon and returned them to the earth. It planned to land 14 of them on the Surface, but two failed. That is about $2.1 billion per landed astronaut or 17.5 times the cost per Surveyor robot. The lunar astronauts brought back 382 kg of lunar rocks and soil to Earth, greatly contributing to our knowledge of the Moon's composition and geological history. Their discoveries changed our understanding of the solar system.

Convince me that the humans on the Moon did less than 17.5 times the science that the Surveyor robots did.

Incidentally, Apollo also spurred advances in many areas of technology incidental to rocketry and human spaceflight, including avionics, telecommunications, and computers. The smartphone you carry in your pocket is largely a result of the Apollo program as is your laptop, your desktop computer and a number of other technologies - digital flight control systems, emergency (space) blankets, quake-proofing, rechargeable hearing aids, improved dialysis, quartz crystal clocks, heart pacemakers and improved thermal protection for firefighters are just a few.

Convince me that the results and benefits of sending humans to the moon could all have come from sending robots, and that it wasn't worth the risk or the money!
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Old 9th March 2021, 06:30 PM   #208
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Originally Posted by smartcooky View Post
The Tyranny of the Rocket Equation
"'the rocket' is taken to mean 'the rocket and all of its unburned propellant'.
"...there is a limit to the amount of payload that the rocket can carry, as higher amounts of propellant increment the overall weight, and thus also increase the fuel consumption."
"The rocket equation can be applied to orbital maneuvers in order to determine how much propellant is needed to change to a particular new orbit, or to find the new orbit as the result of a particular propellant burn. When applying to orbital maneuvers, one assumes an impulsive maneuver, in which the propellant is discharged and delta-v applied instantaneously."
I'm aware of the rocket equation, so I don't see why you're telling me this.

Quote:
Asad's answer from a few years back on Stack Exchange pretty much sums it up

https://physics.stackexchange.com/qu...ig/88163#88163

"Upper limit on payload:

A very interesting thing happens near the inflection point of the rocket mass - fuel mass curve. Before the inflection point, adding more fuel allowed us to hoist a larger payload to the desired velocity.

However, somewhere around 4⋅106 kg of fuel mass (for our selected parameter values) we discover that adding more fuel starts to decrease the payload that can be hoisted! What is happening here is that the cost of the additional fuel having to fight against gravity begins to win out against the benefit of having a high fuel to payload mass ratio.

This shows there is a theoretical upper limit to the payload that can be hoisted on Earth using the propellant technology we have available. It is not possible to simply keep increasing the payload and fuel masses in equal proportion in order to lift arbitrarily large loads, as would be suggested by using the Tsiolkovsky equation with no extra terms for gravity."
This is talking about launching payloads from the earth. I'm not exactly sure what constrains are leading to that inflection point, but we're talking about a completely different issue of payloads, after assembly in LEO

Your claim is that two payloads launched from earth will get to mars, but if assembled into a single payload in LEO they won't have enough fuel to get to Mars.

The fuel was enough to get them there separately. So how exactly do they need more fuel when assembled and put on a single rocket?

Quote:
If the payload weighs X, you need Y amount of fuel to get it to LEO.

From there, if you need to go anywhere else MEO, GEO, SSO, the Moon, Mars or another planet, value of Y (the amount of fuel you need) is greater, so you need bigger fuel tanks to carry the additional fuel into orbit. This increases the weight of of the rocket so you need even more fuel.
Of course. But we're talking about two payloads that both already have enough fuel to get to Mars independently. So this isn't a difference between separate launches and assembly in orbit into a single payload.

Quote:
The same applies to boosting an object from LEO to another orbit, including a transfer orbit to another body... the greater the mass of the object, the more inertia you have to overcome to move it to its new orbit and that means more fuel and therefore, more weight. You have to get that extra fuel into LEO somehow, so one or both of your two launches that you used to put the components of your bigger Mars rover and EDL into LEO also has to carry this extra fuel. That either means your initial rocket has to be bigger, or you will need a third launch to bring that extra fuel into orbit.
We have the equivalent of 2 perseverance missions. It will need more fuel than one perseverance mission. You haven't given an argument for why it will need more fuel than two perseverance missions.
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Old 10th March 2021, 04:02 AM   #209
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Originally Posted by theprestige View Post
IRRC, Hubble wasn't actually designed to be repaired in orbit. Massimo was struggling because nothing had been designed with his task in mind. That he accomplished it at all is pretty amazing, IMO.

And also let's note that he carried out these repairs outside of a clean room.

*snip*
Ehr, in orbit? Would be hard to find a cleaner room than that.

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Old 10th March 2021, 04:29 AM   #210
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Originally Posted by Roboramma View Post
I'm aware of the rocket equation, so I don't see why you're telling me this.
Really?

Originally Posted by Roboramma View Post
This is talking about launching payloads from the earth. I'm not exactly sure what constrains are leading to that inflection point, but we're talking about a completely different issue of payloads, after assembly in LEO
You missed this bit

Originally Posted by smartcooky View Post
"The rocket equation can be applied to orbital maneuvers in order to determine how much propellant is needed to change to a particular new orbit, or to find the new orbit as the result of a particular propellant burn. When applying to orbital maneuvers, one assumes an impulsive maneuver, in which the propellant is discharged and delta-v applied instantaneously."
I guess you don't understand the rocket equation as well as you thought you did.

Originally Posted by Roboramma View Post
Your claim is that two payloads launched from earth will get to mars, but if assembled into a single payload in LEO they won't have enough fuel to get to Mars.

The fuel was enough to get them there separately. So how exactly do they need more fuel when assembled and put on a single rocket?
You appear to be misunderstanding the issue.

Launching two payloads A(X+Y) and B(X+Y) to Mars appears superficially the same as taking one of the payloads - A - splitting it into X and Y and making each of them twice as big, so 2X and 2Y, launching them separately into LEO, assembling them together on orbit A(2X+2Y) and boosting them to Mars.

The reality is that you don't get to do the on orbit assembly for free. That comes at a cost. At the very least, you will need some sort of manuevering system to carry out the task of linking these two machines (the rover and the skycrane) and if you think that will be as easy and docking them together like a capsule to the ISS, think again.

Take this rover...


...assemble it to the skycrane...


... so that it ends up looking like this...


... then insert the whole thing into its backshell, like this...


... then bolt this heat shield in place.


You have to do all this in space, with no additional equipment or resources over and above what it would have taken to launch two original sized rovers separately and send them to Mars. If you cannot do that, then your claim "We have the equivalent of 2 perseverance missions" fails!

Now, here is the reality...

You might be able to pre-assemble items 1, 2 and 3 and launch them as one payload, but I seriously doubt it. I have watched the video and live feed of how this thing was assembled. The assembly team needs access to the top of the rover as well as both the top and the bottom of sky-crane.

However, you cannot pre-assemble items 4 and 5 and launch that as an assembly. The heat shield is mechanically attached to the back-shell but not to the rover or the sky-crane.

Now, this is not going to be able to be done by some kind of docking manuever. In order to make this work, you will need a team of perhaps four to six mission specialists. You will have to launch these guys into space to do the job, so that means a manned launch (more expense and more fuel), and then a re-entry and recovery when they are done. This assembly takes many hours of intricate, painstaking work. You might need to use the ISS as a base of operations, so that means getting into a 405 km orbit, thats higher than the one the Mars Missions do their usual TMI burn from (so more fuel expended to get your two payload launches and the assembly team to a higher orbit).

All this would just be a waste of time anyway... I have already shown that there is no way to land a 2000+ kg rover on the surface of Mars using the Skycrane/supersonic parachute EDL concept. The atmosphere is not thick enough or dense enough to allow any realistically sized parachute to arrest the entry vehicle's velocity sufficiently to land it - essentially, you will run out of room. It has already been said by the guy who actually conceived this method that these two rover missions are pushing the very edge of the capability of this landing concept. If they want to go larger, they will have to come up with something different in the same way that they came up with this method when they realised that the airbag/lithobraking EDL system had reached its mass limit.
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Old 10th March 2021, 05:32 AM   #211
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Originally Posted by smartcooky View Post
Really?
Yes.



Quote:
You missed this bit
Actually, I didn't.



Quote:
I guess you don't understand the rocket equation as well as you thought you did.
Not seeing where I've misunderstood the rocket equation so far. Are you actually suggesting that I think the rocket equation only applies to launches from the earth? Somehow once something's in orbit it no longer applies? You got that from my post?

This was the quote from your post that I said applied to launches from the earth:
Quote:
However, somewhere around 4⋅106 kg of fuel mass (for our selected parameter values) we discover that adding more fuel starts to decrease the payload that can be hoisted! What is happening here is that the cost of the additional fuel having to fight against gravity begins to win out against the benefit of having a high fuel to payload mass ratio.

This shows there is a theoretical upper limit to the payload that can be hoisted on Earth using the propellant technology we have available. It is not possible to simply keep increasing the payload and fuel masses in equal proportion in order to lift arbitrarily large loads, as would be suggested by using the Tsiolkovsky equation with no extra terms for gravity."


Quote:
You appear to be misunderstanding the issue.
Possibly, which is why I'm hoping you can clarify. But every time you try to clarify you start talking about different issues.

Quote:
Launching two payloads A(X+Y) and B(X+Y) to Mars appears superficially the same as taking one of the payloads - A - splitting it into X and Y and making each of them twice as big, so 2X and 2Y, launching them separately into LEO, assembling them together on orbit A(2X+2Y) and boosting them to Mars.
Yes, it is.

Quote:
The reality is that you don't get to do the on orbit assembly for free. That comes at a cost. At the very least, you will need some sort of manuevering system to carry out the task of linking these two machines (the rover and the skycrane) and if you think that will be as easy and docking them together like a capsule to the ISS, think again.
Sure, I can accept that there's a cost to the assembly stage, and this will eat away at the total payload you can get for the same fuel at earth's surface.

On the other hand, you completely ignored the fact that we only need one set of engines for the boost instead of two. Why are you convinced that these second order effects will be net negative instead of positive?

This also isn't the issue that you were talking about earlier.

Quote:
You have to do all this in space, with no additional equipment or resources over and above what it would have taken to launch two original sized rovers separately and send them to Mars. If you cannot do that, then your claim "We have the equivalent of 2 perseverance missions" fails!
This is ridiculous. We're talking about theprestige's idea of building the infrastructure for an orbital spaceyards. Of course there is a cost to doing that. But in this scenario that additional equipment and resources is already there. Is it worth the cost of building that for whatever benefit we get over the course of it's lifetime in missions assembled in orbit?

That's a different question. Maybe, maybe not.

Quote:
All this would just be a waste of time anyway... I have already shown that there is no way to land a 2000+ kg rover on the surface of Mars using the Skycrane/supersonic parachute EDL concept. The atmosphere is not thick enough or dense enough to allow any realistically sized parachute to arrest the entry vehicle's velocity sufficiently to land it - essentially, you will run out of room. It has already been said by the guy who actually conceived this method that these two rover missions are pushing the very edge of the capability of this landing concept. If they want to go larger, they will have to come up with something different in the same way that they came up with this method when they realised that the airbag/lithobraking EDL system had reached its mass limit.
It does seem reasonable to me that there are scaling issues with the parachute part of the system that could make it no longer viable with larger masses.
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Old 10th March 2021, 05:39 AM   #212
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Originally Posted by MRC_Hans View Post
Ehr, in orbit? Would be hard to find a cleaner room than that.

Hans
In the article I linked to above NASA has concluded it would be better to assemble complex equipment up in orbit, both cost wise and safety and risk. Sending everything up on one rocket means one explosion destroys everything, one rocket containing one component exploding is a set back and you can send a replacement.
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Old 11th March 2021, 12:12 PM   #213
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Originally Posted by Roboramma View Post
Not seeing where I've misunderstood the rocket equation so far. Are you actually suggesting that I think the rocket equation only applies to launches from the earth? Somehow once something's in orbit it no longer applies? You got that from my post?
Yes, and why wouldn't I?

"This is talking about launching payloads from the earth. I'm not exactly sure what constrains are leading to that inflection point, but we're talking about a completely different issue of payloads, after assembly in LEO"
Whether or not you actually believe this, or didn't mean to say this, those are your words - you are clearly inferring that launching from the earth and boosting/changing from one orbit to another are different in terms of the physics. They are not. In each case you have a mass in a gravity well and you are trying to move that mass - the rocket equation applies

Originally Posted by Roboramma View Post
Possibly, which is why I'm hoping you can clarify. But every time you try to clarify you start talking about different issues.
Not different issues, more issues with expanded clarifications that are directly related to the claim

You cannot just isolate one thing in a massive operation like landing a heavy payload on anther planet, say "yes that is possible" and conclude that everything is good to go for the whole mission. Everything is related and everything has an effect on the mission, right down to the last nut, bolt, screw and washser, even the thickness of the paint layers, even the temperture of the fuel.

Originally Posted by Roboramma View Post
Sure, I can accept that there's a cost to the assembly stage, and this will eat away at the total payload you can get for the same fuel at earth's surface.

On the other hand, you completely ignored the fact that we only need one set of engines for the boost instead of two. Why are you convinced that these second order effects will be net negative instead of positive?
You are trying to accelerate at least twice the mass (probably more), so your one engine will have to be much bigger and/or you will need to burn more fuel. The gains of only having your one engine instead of two is cancelled out by the fact that it will be bigger (and will weigh more) and/or you will need to have more fuel (which will also weigh more). There are no free lunches in space technology - every gramme of payload comes at a cost, whether it is being launched from the earth's surface, or boosted from LEO to a transfer orbit.

Originally Posted by Roboramma View Post
This is ridiculous. We're talking about theprestige's idea of building the infrastructure for an orbital spaceyards. Of course there is a cost to doing that. But in this scenario that additional equipment and resources is already there. Is it worth the cost of building that for whatever benefit we get over the course of it's lifetime in missions assembled in orbit?
I was responding to this as well..

Originally Posted by Myriad View Post
Imagine if you will two skycranes of roughly the present design, flying independently but in tight synchrony, sharing the load of a single payload. If you could keep their operations synchronized it would work. That would be difficult, though, and in any case it would be really awkward to try to get them into that configuration after the earlier atmospheric entry phases. So instead, bolt them together side by side (or rather, make one larger skycrane of those dimensions).
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Old 11th March 2021, 03:31 PM   #214
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If anybody wants to learn more about the helicopter that will be deployed as part of this mission, there is a lecture on youtube happening in about 4 hours (1900 PDT, 2200 EST, 0300 UTC);

https://www.jpl.nasa.gov/jpl-and-the...pters-in-space
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Old 11th March 2021, 05:12 PM   #215
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Cool! Veritasium also did an overview before it was launched.
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Old 18th April 2021, 08:42 PM   #216
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Found this livestream on Youtube, which is supposed to cover Ingenuity's first flight live (well, of course it can't be live as in we see it in real time. It'll be at least 15 minutes later, the time it will take a signal to reach Earth from Mars).

Right now though, they are showing historical NASA videos. I'm not sure exactly when the actual broadcast will begin.

https://www.youtube.com/watch?v=0wzFSrM_JQA
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Old 18th April 2021, 08:43 PM   #217
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Cautiously optimistic.
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Old 18th April 2021, 08:44 PM   #218
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Here's the official NASA feed, btw. It says that it's live in 6 hours, which means that I'll get to watch it.

https://www.youtube.com/watch?v=p1KolyCqICI
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Old 18th April 2021, 10:10 PM   #219
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This is amazing. My grandfather was a teenager before the first powered flight. Now we are going to do it...on Mars. Something he probably could not even have imagined when he was my age.
These are the days of miracle and wonder
This is the long-distance call
The way the camera follows us in slo-mo
The way we look to us all
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Old 18th April 2021, 10:24 PM   #220
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Originally Posted by arthwollipot View Post
Here's the official NASA feed, btw. It says that it's live in 6 hours, which means that I'll get to watch it.

https://www.youtube.com/watch?v=p1KolyCqICI
Thanks.
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Old 18th April 2021, 11:02 PM   #221
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Originally Posted by DevilsAdvocate View Post
This is amazing. My grandfather was a teenager before the first powered flight. Now we are going to do it...on Mars. Something he probably could not even have imagined when he was my age.
It still amazes me that the lives of Orville Wright and Neil Armstrong overlapped.
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Old 19th April 2021, 01:45 AM   #222
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Originally Posted by Puppycow View Post
Thanks.
Oh, look, they turned the comments off. Losers!
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Old 19th April 2021, 03:11 AM   #223
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Should be starting presently (about 3 more minutes)
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Old 19th April 2021, 03:18 AM   #224
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Originally Posted by Elagabalus View Post
Oh, look, they turned the comments off. Losers!
There is a chat though
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Old 19th April 2021, 03:53 AM   #225
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IT FLEW!!!

And photographed its own shadow

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Old 19th April 2021, 03:58 AM   #226
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I saw a video on the livefeed. It only went up and back down again, but it flew.
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Old 19th April 2021, 04:15 AM   #227
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Today I watched history being made from 289 mio km away..

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Old 19th April 2021, 04:16 AM   #228
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I watched it live too. A perfect first flight.
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Old 19th April 2021, 05:52 AM   #229
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Here's the Live feed.

YouTube Video This video is not hosted by the ISF. The ISF can not be held responsible for the suitability or legality of this material. By clicking the link below you agree to view content from an external website.
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Old 19th April 2021, 07:00 AM   #230
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My wife's great-grand father lived near Kittyhawk. She remembers him saying when she was a child he thought at that time man would never fly.

You all know this is just cgi.

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Old 19th April 2021, 04:01 PM   #231
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Originally Posted by Puppycow View Post
I saw a video on the livefeed. It only went up and back down again, but it flew.
100% success according to the mission parameters.
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Old 19th April 2021, 04:32 PM   #232
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I get chill bumps every time someone mentions that a piece of the original Wright Flyer is attached to Ingenuity. That is just too cool.
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Old 20th April 2021, 12:02 AM   #233
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Originally Posted by Puppycow View Post
I saw a video on the livefeed. It only went up and back down again, but it flew.
That’s pretty much the definition of a flight!
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Old 20th April 2021, 02:00 AM   #234
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Originally Posted by Steve001 View Post
My wife's great-grand father lived near Kittyhawk. She remembers him saying when she was a child he thought at that time man would never fly.

You all know this is just cgi.
It does bother me a bit that often when I'm seeing clips like this I can't tell if it's a CGI simulation or the real thing.
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Old 20th April 2021, 07:52 PM   #235
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Originally Posted by alfaniner View Post
It does bother me a bit that often when I'm seeing clips like this I can't tell if it's a CGI simulation or the real thing.
You can tell from the pixels and the shadows are wrong.
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Old 21st April 2021, 10:35 PM   #236
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Old 21st April 2021, 11:39 PM   #237
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Quote:
MOXIE (Mars Oxygen In-situ Resource Utilization Experiment), a small, gold box-shaped instrument on the rover, successfully demonstrated a solid oxide electrolysis technology for converting the Martian atmosphere to oxygen. The atmosphere on Mars is about 95% carbon dioxide.
Good gravy! That's some moxie! We are doing things on Mars that I can't even imaging doing on Earth. Or in my bedroom. Although, one night, in college, just as an experiment, with this sorority girl, I think I did use solid oxide electrolysis technology. I might wrong.
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Old 22nd April 2021, 01:51 AM   #238
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Originally Posted by arthwollipot View Post
Using electrolysis of CO2 even.
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Old 25th April 2021, 02:17 AM   #239
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I thought this video about the MOXIE experiment to make O2 from CO2 was pretty interesting:

YouTube Video This video is not hosted by the ISF. The ISF can not be held responsible for the suitability or legality of this material. By clicking the link below you agree to view content from an external website.
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Also, the helicopter made a second flight and a third one is planned for Sunday (today). It might be Monday depending on where you live though.
Quote:
During the second flight, on April 22, Ingenuity autonomously climbed to 5 meters (16 feet) in height, traveled 2 meters (7 feet) to the east and back, and remained airborne 51.9 seconds. It also made three turns, totaling about 276 degrees.
https://twitter.com/NASAPersevere/st...98304688758785

(Full color photo taken from the helicopter during the second flight.)

https://twitter.com/NASAPersevere

Here's what should happen on the third flight:
Originally Posted by JPL
Faster, farther, bolder. #MarsHelicopter is set for flight No. 3 on April 25. http://go.nasa.gov/3gArAmw

Flight plan:
Speed: ~4.5mph
Range: 330ft (100m) roundtrip
Altitude: 16ft (5m)

Data expected later Sunday. Til then, peep this shot of rover tracks from the 2nd flight.
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Old 25th April 2021, 02:19 AM   #240
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Obvious fake - look at all those tyre tracks!!
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