Video from Artemis II flyby of the Moon will not initially look spectacular

"Don't expect hi-res video."

See full article...

 

[DCStone]

You can ignore the phase, you just need to reverse the polarity.

Isn't that just a 180° (pi radians) phase change, though?

 

[randomuser42]

My entire point was to quote myself from earlier "[h]owever, I am quite disappointed that NASA didn't put the emitter on the earth-facing side of the capsule during the approach."

Someone else mentioned this, but not in reply to you, that the optical comms aren't a part of Orion's baseline design so they're in the experimental module bay, which is on the side it happens to be on and that's that, as far as the design goes. That design probably predates the existence of o2o

 

[Anacher]

So I wanted to add some data to everyone's thoughts here for O2O. Which might help to answer some questions.

The O2O terminal is on the side of Orion, so it won't always have line of sight to the ground. There are 3 optical ground stations supporting O2O. One at White Sands, NM, second at OCTL in CA, and at ANU in Canberra, AUS. Any contact times are limited by visibility of those stations, orientation of Orion and weather at the stations. Basically any of the same limitations that a high gain RF system would have (except for the weather/clouds).

O2O is a supplemental communication link. So not expected to have it on at all times. Not nearly enough ground stations for full globe coverage.

Both the ground terminals and flight terminal have a region around the sun that they don't like to point in to, for different reasons (design determines how big these regions are, and what the impact is).

The sun is much more energetic than any of our comm systems, so if you get too close to the sun edge, your signal gets swamped out (RF has this same problem). But some designs won't let you get that close due to possible optical or thermal damage.

Given that Orion maneuvers all over the place I'm sure the flight terminal won't be impacted by getting sun too close to the receive aperture, but it wouldn't be able to get any comm signal in.

 

[gosub]

You can monitor NASA's deep space network here. It's always cool when they are talking w/ the Voyagers. Voyager 1 is approaching 1 light day distance away(!)
There's a great 60 Symbols youtube video on the challenges of deep space communications.
Also relaying from the surface via an orbiter is how much of the communications w/ Mars rovers works

Thank you for sharing! Love it!

 

[AliSard]

Integrity

No spacecraft has ever been named more ironically.

I know at least four people who would like a word.

 

[Derecho Imminent]

Isn't that just a 180° (pi radians) phase change, though?

Why on earth are you americans still using degrees!!!
/jk

 

[spaceminions]

This is the old latency vs bandwidth discussion - the speed at which a signal travels across space (whether through wires/fiber cables, or through space itself as radio or lasers) is distinct from bandwidth. So far as we know, the upper bound of latency is the inverse of the speed of light - that is the best you can do for latency is (C/distance), which will give you an answer in a unit of time (usually seconds, but you could use a derived unit like, milliseconds, microseconds, etc - in space, the units might be minutes, hours, or days, because the distances are so vast).

But bandwidth is how much data you can transmit PER second. With EMR (ElectroMagnetic Radiation), such as radio, infrared, visible light, ultraviolet, x-rays, etc, you get ever increasing bandwidth as you increase frequency bands.

This is just a function of frequencies, essentially.

For example, in the radio band between 100Mhz and 200Mhz, you have only 100Mhz of total available bandwidth - also, this band is already allocated for other uses, such as terrestrial FM Radio (going from roughly 88Mhz to 108Mhz, Amateur Radio, going from 144-148Mhz, and many other users who've been given slices).

But regulatory allocation aside, the main point remains.

Now consider that from 1Ghz to 2Ghz, again, allocations aside, you have a full Ghz of available bandwidth.

Now, infrared goes from 300Ghz all the way up to 400TerraHertz - that is a giant, giant bandwidth. I don't know if they are using all of that - I doubt it, I doubt they have anywhere near the amount of data needed to saturate such a link.

So the speed the IR waves travel through space is the same as radio, but the bandwidth is much larger.

As I said, switching from the radio side to the optical side is a big deal; all of a sudden you can't use all that bandwidth in one transmitter. A radio or electrical transmitter can produce arbitrary frequency and phase within a generous minimum and maximum spec, even though practicalities limit this for anything that needs to go out an antenna properly. Practically, you should be able to do idk, 20GHz of bandwidth by using mmWave bands? And if you had enough signal strength and nice equipment, you might have 12 bits per symbol like wifi 7 does, so 2-300 gigabits per polarization, maybe dual polarization to double that like usual, and maybe in certain situations some spatial multiplexing - but probably not this one. But with lasers, regardless of the carrier frequency your modulator has to be able to keep up. Even if you have the best IQ modulator I believe you would get on the order of 100GHz symbol rate with 4 to 6 bits per symbol, maybe a bit more now. But that's per independent laser frequency; you can still have multiple lasers on different wavelengths at once. You just can't run a single laser at hundreds of terahertz of bandwidth, diving down to thermal and up to near infrared repeatedly. So, being so much higher is, "in a vacuum", not orders of magnitude better than mmwave per channel. Both are highly excessive for these video streams, and it's still all about actual practical concerns like signal strength for the small transmitter size. I do assume you can do dual-polarization just as well with lasers if not better, since the ionosphere probably won't rotate them as much, and I imagine you'd use opposite handed circular but I'm just guessing.

 

[TheSolutor]

We finally know what HDMI means.

Highly Debatable Moon Imaging

 

[DCStone]

Why on earth are you americans still using degrees!!!
/jk

Who are you calling an american? Do I have to send in the rabid beavers?!
/jk

 

[yakinabe]

I realize it's a non-critical system. But if it worked, people would really rather see high-definition video of the flyby than a slideshow. It's like the launch. ... NASA needs public support. Good livestream quality would have been a way to accomplish that. Is it mission critical? No - not if one narrowly defines the mission as being the objectives of the Artemis II launch. However, that sort of thing IS mission critical for NASA as a whole.

Are you watching the livestream? Do you think it's so bad as to cost NASA public support? Especially considering most people are watching it on smartphones and little YouTube browser windows on screen? We can also see that the astronauts are taking a lot of photos on their Nikon cameras which wouldn't have been livestreamed anyway.

 

[Wickwick]

Are you watching the livestream? Do you think it's so bad as to cost NASA public support? Especially considering most people are watching it on smartphones and little YouTube browser windows on screen? We can also see that the astronauts are taking a lot of photos on their Nikon cameras which wouldn't have been livestreamed anyway.

From the article:

“Don’t expect high-res video,” added Judd Frieling, Artemis II ascent flight director, “but you will have, as Kelsey mentioned, the SAW cameras through our nominal low-rate video.”

It's not bad enough it's low-resolution. It will also be low framerate. Yes, I think people will be disappointed by the craptastic quality of the video and it will cost them what would have otherwise been an opportunity for a PR win.

No, I don't think it will diminish support. But it misses a change to gain support. So in the end, yes, I truly think it's a big loss.

 

[Meee3]

Regarding the on-board cameras....
They have Nikon D5 and Z9 cameras (the latter added "at the last minute" with direction apparently from Isaacman). Does anyone know what lenses the crew are using with those cameras? The live feed is referencing "long" and "wide" but I'm curious of the specifics.

Edited to add: I'm referring to the moon observation cameras, rather than the GoPros on the solar arrays, and internal cabin cameras. I realize those are there and separate from the above noted cameras.

 

[plainsman32]

Maybe a constellation of Starlinks in lunar orbit with further deployed relays between earth and moon? Get to work SpaceX

 

[Snark218]

No, I don't think it will diminish support. But it misses a change to gain support. So in the end, yes, I truly think it's a big loss.

No. People who are already interested in Artemis and space exploration and support NASA and its mission will be disappointed. Precisely nobody who does not support NASA is going to go, "oh hey, this is certainly an enviable framerate and resolution, actually a moon mission is a fantastic idea and NASA should be better funded, how did I miss it before." They're not watching. By definition, they're not interested. If the good cameras captured anything that might be inspiring to schoolkids or especially beautiful, nobody was going to see that in the live stream anyway.

 

[NetMage]

Why does "made for Orion" necessarily mean "able to point near the Sun"?

Because the Artemis II flight path has been known for a very long time?

 

[JaneBird]

I'm just happy to be here. Going to take extra time to gaze at the moon tonight knowing I'm also looking towards four humans.

I might be worn out, burned out, and generally weary but I am doing my best to remind myself of the kinds of marvels people can accomplish through collaboration.

 

[azazel1024]

I would add that O2O is an experimental system. It isn't part of the baseline Orion spacecraft and thus the only spot for it is in the modular experimental bay which is space reserved for mission specific payloads.

In the future it would probably good to have two such optical transceivers and a 3+ sat constellation around the moon and another 3+ sat constellation around the Earth. A comprehensive optical to optical communication network. If you put relays at the EML as well then you could always route around the location of the sun relative to the spacecraft and Earth.

However like all engineering it is crawl-walk-run. The crawl level worked largely as expected and provided tangible benefits. There should be future budgets to expand that concept into a more comprehensive system. Lunar ground assets are unlikely to carry optical comm gear but if they can relay data to a sat overhead using a high throughput radio link and the sat then send it to the optical network they don't need one.

A lot of this. From what I pulled up, the Earth side is...well Earth side. If it was in orbit, the day vs night would be much less of an issue. You'd likely only be blinded if you were within a couple of degrees of the sun then.

But a lunar relay makes the most sense. Even if the actual relay from the Moon to the Earth and back is laser based. Pointing an optical telescope and tracking is going to be a LOT more complicated on things in motion, especially rapid motion. So, you'd really only want something like that on a fixed ground station or something moving in a relatively predictable manner. A landing spaceship or ground rover would probably make terrible platforms for that. But if you've got a lunar relay constellation, I'd assume you could easily get away with an AESA radio array, or three for very high speed coms. Heck, if the constellation was relatively low, you could probably get away with an isotropic antenna if using a fair amount of bandwidth and a reasonably powerful radio (I don't mean kw of radio power, I mean tens of watts).

 

[NetMage]

Does anyone know what lenses the crew are using with those cameras?

I see the D5 has the 14-24 and 80-400 but don’t see anything about the Z9.

 

[JohnDeL]

No. People who are already interested in Artemis and space exploration and support NASA and its mission will be disappointed. Precisely nobody who does not support NASA is going to go, "oh hey, this is certainly an enviable framerate and resolution, actually a moon mission is a fantastic idea and NASA should be better funded, how did I miss it before." They're not watching. By definition, they're not interested. If the good cameras captured anything that might be inspiring to schoolkids or especially beautiful, nobody was going to see that in the live stream anyway.

I'm not so sure about that. Do you remember the bump NASA got from the Earthrise photo? Admittedly, it was short-lived, but it did make NASA more popular for a few months.

 

[Autapomorphy]

They have Nikon D5 and Z9 cameras.

That's an interesting choice. The D5 is a sports and wildlife camera, with a design focused on high performance autofocus for tracking fast moving subjects and high burst rates. This is important if you're photographing, say, birds of prey and trying to capture the moment where a raptor grabs a songbird.

None of that is necessary for photographing the moon which isn't darting around unpredictably. Were I asked to select a Nikon DSLR, I'd go with the D850 as Nikon's premier portrait/landscape DSLR.

 

[Wickwick]

A lot of this. From what I pulled up, the Earth side is...well Earth side. If it was in orbit, the day vs night would be much less of an issue. You'd likely only be blinded if you were within a couple of degrees of the sun then.

But a lunar relay makes the most sense. Even if the actual relay from the Moon to the Earth and back is laser based. Pointing an optical telescope and tracking is going to be a LOT more complicated on things in motion, especially rapid motion. So, you'd really only want something like that on a fixed ground station or something moving in a relatively predictable manner. A landing spaceship or ground rover would probably make terrible platforms for that. But if you've got a lunar relay constellation, I'd assume you could easily get away with an AESA radio array, or three for very high speed coms. Heck, if the constellation was relatively low, you could probably get away with an isotropic antenna if using a fair amount of bandwidth and a reasonably powerful radio (I don't mean kw of radio power, I mean tens of watts).

There are multiple EML points though. L1 is earth-side, but 2 is on the far side and 4 and 5 are well in-front/behind the moon. From anywhere in lunar orbit, you should be able to see at least 2 of the four locations so you're guaranteed to have one that's inline with the sun. However, I think 4 satellites at different phases of NRHO might also satisfy that requirement and be closer than at least L4 and L5.

 

[schnackenpfefferhausen]

Such a potato quality video the moon literally looks like a (off-colour) potato

 

[azazel1024]

This is the old latency vs bandwidth discussion - the speed at which a signal travels across space (whether through wires/fiber cables, or through space itself as radio or lasers) is distinct from bandwidth. So far as we know, the upper bound of latency is the inverse of the speed of light - that is the best you can do for latency is (distance/C) (EDIT: I accidentally had the numerator and denominator flipped; was re-reading and spotted my mistake), which will give you an answer in a unit of time (usually seconds, but you could use a derived unit like, milliseconds, microseconds, etc - in space, the units might be minutes, hours, or days, because the distances are so vast).

But bandwidth is how much data you can transmit PER second. With EMR (ElectroMagnetic Radiation), such as radio, infrared, visible light, ultraviolet, x-rays, etc, you get ever increasing bandwidth as you increase frequency bands.

This is just a function of frequencies, essentially.

For example, in the radio band between 100Mhz and 200Mhz, you have only 100Mhz of total available bandwidth - also, this band is already allocated for other uses, such as terrestrial FM Radio (going from roughly 88Mhz to 108Mhz, Amateur Radio, going from 144-148Mhz, and many other users who've been given slices).

But regulatory allocation aside, the main point remains.

Now consider that from 1Ghz to 2Ghz, again, allocations aside, you have a full Ghz of available bandwidth.

Now, infrared goes from 300Ghz all the way up to 400TerraHertz - that is a giant, giant bandwidth. I don't know if they are using all of that - I doubt it, I doubt they have anywhere near the amount of data needed to saturate such a link.

So the speed the IR waves travel through space is the same as radio, but the bandwidth is much larger.

Excellent explanation. I will be that guy though for a second and say, it does depend on the communications protocol for latency vs bandwidth. Not that probably any reasonable protocol is going to significantly increase latency unless you are talking extremely bandwidth constrained communications methods/frequencies versus less so.

ELF radio latency for TCP/IP is going to increase the latency significantly versus microwave as an example, just because the symbol rate over ELF is so much incredibly slower that just receiving and transmitting an ACK packet is going to take so long versus microwave. If your communications protocol was one binary bit, then functionally there would be no real difference in latency between ELF or microwave.

If you needed to send an entire message and then receive a reply (even with no processing time between when the message is finally received and transmitting a reply) then ELF would pose a massive latency penalty over microwave. Microwave would likely pose a massive latency penalty over IR laser to, unless the message/data was very short.

But this would only apply to something like terrestrial distances where a 100baud rate for ELF is going to add a massive transmission time penalties to determine total latency. At something like Viking probe distances, well if you need to transmit 100kb of data, even a 100 baud rate isn't that much of a latency penalty versus 1gbaud when it takes 1 day for the signal to arrive to start with. You'd be adding a tiny fraction of a percent in lag.

 

[azazel1024]

There are multiple EML points though. L1 is earth-side, but 2 is on the far side and 4 and 5 are well in-front/behind the moon. From anywhere in lunar orbit, you should be able to see at least 2 of the four locations so you're guaranteed to have one that's inline with the sun. However, I think 4 satellites at different phases of NRHO might also satisfy that requirement and be closer than at least L4 and L5.

Sure, but having relay satellites in Earth's orbit, should also generally take care of that blinding. It isn't that hard to shield an optical receiver/telescope from a bright light source a few degrees off axis. It would let you operate the lunar relay satellites in much lower lunar orbit to make radio reception easier/higher bandwidth for anything transmitting from the moon to the relay satellite. More satellites than operating relay satellites at Lagrange points, but also those relay satellites would be significantly closer to end users on the moon or in lunar orbit.

 

[EllPeaTea]

Because the Artemis II flight path has been known for a very long time?

But it hasn’t. The flight path in relation to the Earth and the moon has been known, but not in relation to the sun, which is the actual problem here.

Unlike Apollo, which targeted specific phases of the moon, Artemis II is limited by having the moon in the southern sky, and also the reduced rentry corridor length.

 

[DCStone]

That's an interesting choice. The D5 is a sports and wildlife camera, with a design focused on high performance autofocus for tracking fast moving subjects and high burst rates. This is important if you're photographing, say, birds of prey and trying to capture the moment where a raptor grabs a songbird.

None of that is necessary for photographing the moon which isn't darting around unpredictably. Were I asked to select a Nikon DSLR, I'd go with the D850 as Nikon's premier portrait/landscape DSLR.

What about low-light performance? While not as much of an issue for the direct sun side, the other side is not going to be anywhere near as bright. Might they want the high burst so the individual images can be stacked together for better image quality?

Also, does anyone know how the relative velocity during closest approach might affect which camera settings to use? It's a lot easier figuring that out for my ancient Nikon D50 on a tripod shooting from earth, but the moon isn't moving much relative to the camera during the exposure time.

 

[Fred Duck]

That's an interesting choice. The D5 is a sports and wildlife camera, with a design focused on high performance autofocus for tracking fast moving subjects and high burst rates. This is important if you're photographing, say, birds of prey and trying to capture the moment where a raptor grabs a songbird.

None of that is necessary for photographing the moon which isn't darting around unpredictably. Were I asked to select a Nikon DSLR, I'd go with the D850 as Nikon's premier portrait/landscape DSLR.

I would've thought since it's meant for high-speed, then it would focus especially quickly and so shutter lag would be a non-issue.

An exaggerated, pixelated version of a photo of the moon taken by an Artemis II crew member at the fourth day of the mission.

Pro tip: If you have a Samsung smartphone to hand...

 

[GenericAnimeBoy]

It's like the launch. There was apparently awesome high-def footage looking down the launch tower that was released only after the mission was progressing. Why on earth wouldn't NASA have prioritized that? NASA needs public support. Good livestream quality would have been a way to accomplish that.

NASA is understandably hesitant about releasing live video streams from crewed missions during energetic phases of flight, especially where doing so might attract greater-than-usual public attention. True, releasing the footage later is less impactful than it would be live, but consider how that dramatic camera angle would look if it were running over and over on the evening news after an incident. Even if the launch escape system worked perfectly and the crew survived, that's a PR guy's nightmare. Best to keep the official launch coverage clinical and release the flashy stuff afterwards.

 

[SomewhereAroundBarstow]

OMG. I've been watching the stream and realized the conspiracy theorists are right. This is obviously faked and you can tell because there's no shark visible at all.

 

[yakinabe]

That's an interesting choice. The D5 is a sports and wildlife camera, with a design focused on high performance autofocus for tracking fast moving subjects and high burst rates. This is important if you're photographing, say, birds of prey and trying to capture the moment where a raptor grabs a songbird.

The D5 has been in use on ISS since 2017, presumably because it's a flagship model - i.e the most ruggedized and durable model. So that's the proven, reliable option. They chose the Z9 for Aretemis moon landing missions, and been testing modified versions under vacuum. Z9 seems uniquely suitable since it doesn't have a mechanical shutter.

 

[Wickwick]

NASA is understandably hesitant about releasing live video streams from crewed missions during energetic phases of flight, especially where doing so might attract greater-than-usual public attention. True, releasing the footage later is less impactful than it would be live, but consider how that dramatic camera angle would look if it were running over and over on the evening news after an incident. Even if the launch escape system worked perfectly and the crew survived, that's a PR guy's nightmare. Best to keep the official launch coverage clinical and release the flashy stuff afterwards.

If the rocket blows up, there's going to be bad PR regardless. There will be plenty of NASA-provided and third-party footage regardless. The footage will come out through FOIA requests if nothing else. Eschewing good PR because of the possibility of bad PR is the epitome of running scared. I'm not saying it's not the reason. But if it is the reason that footage wasn't shown, it's symptomatic of all the worst shortcomings of NASA.

 

[yakinabe]

I'm not so sure about that. Do you remember the bump NASA got from the Earthrise photo? Admittedly, it was short-lived, but it did make NASA more popular for a few months.

And that was an image taken with a film camera, and released after they landed.

 

[TheSolutor]

This is just a function of frequencies, essentially.

This is confusing, albeit not wrong.

Bandwidth depends on how much wide a channel is. say 8MHz for a TV channel

And in 8 MHz you can transmit the same amount of data no matter if your channel goes from 200 to 208 MHz or from 900 to 908MHz, or from 3.000 to 3.008 GHz

Then for historical reasons the higher in frequency you go, the the easier is to have room for a wider channel, which make the (wrong) assumption that bandwidth is function of the frequency "practically" correct,

 

[henryhbk]

Exactly the end goal would be for individual elements using the shortest link possible. Surface elements talking to overheads sats means the sat is a few hundred km away not 250,000 km away.

A step beyond that is NASA is planning cellular towers on the surface of the moon. So now your surface elements (astronaut on EVA, rover, or remote experiment site) can communication at hundred Mbps or more using <1W of power. Cellular isn't hyperbole or simplification for the masses. NASA intended to use off the shelf 3GPP (i.e. LTE) radios. Why reinvent the wheel. If LTE allows high speed robust communication at a range of up to 10 km on Earth why not use it on the moon.

View attachment 132357


Now the cellular towers will then need to relay it to overhead sats but they are larger and have larger power budget. The overheads sats will need to relay it to Earth but they combined have constant line of sight, can use optical, and also have higher power budgets. In the diagram gateway was the relay but with the likely death of gateway presumably NASA future lunar constellation would be the relay instead.

Are they going to use off the shelf cellular service billing? Oh I am sorry Mrs. Astronaut your plan doesn't have unlimited other-crater data, only unlimited texts. You can pay the additional $100/day to support data in other craters, or there will be overage charges...

 

[alisonken1]

The live feed keeps going bluescreen. I blame Outlook.

I blame Microsoft. outlook is just an app - but it takes an O/S to go blue!

 

[henryhbk]

Could earth put a moon synchronous orbit satellite to be a relay (either to ground or via starlink like Starship does) and sort of bypass the need for surface receivers, get for places like mars etc that doesn't work but the moon is easy to match since it basically matches with us. I assume you could do the reverse around the moon and have an earth synch satellite that links with the one orbiting earth then between those you can hammer at high speed then your folks on the moon only need to talk to that local satellite which is way lower power?

 

[henryhbk]

The optical comm community isn't huge, and has a lot of overlap. And many of the missions work together and build off previous work.

O2O is a terminal that had a nearly identical partner on the ISS. That was ILLUMA-T. ILLUMA-T communicated with LCRD.

OCTL (https://tmf.jpl.nasa.gov/about/octl.php) at JPL is an optical ground station that has supported LLCD, LCRD, TBIRD, DSOC and now O2O.

And these are lasers in the sky, so obviously cat videos are the way to go.

Big Photon is always trying to keep the little guys down...

 

[spaceminions]

That's an interesting choice. The D5 is a sports and wildlife camera, with a design focused on high performance autofocus for tracking fast moving subjects and high burst rates. This is important if you're photographing, say, birds of prey and trying to capture the moment where a raptor grabs a songbird.

None of that is necessary for photographing the moon which isn't darting around unpredictably. Were I asked to select a Nikon DSLR, I'd go with the D850 as Nikon's premier portrait/landscape DSLR.

I mean, maybe they want to reduce the chance the astronauts use the camera suboptimally and miss a shot that would have still been good enough for social media if only they hadn't missed focus or if only they had used more iso. To me, stabilization seems like it would have been worthwhile and neither one has it, and the iso of the d850 seems like it should already be excessive, but idk. Maybe they also wanted a bigger battery or something? maybe the d5 was on an easier to reach shelf? lol

 

[TheSolutor]

I mean, maybe they want to reduce the chance the astronauts use the camera suboptimally and miss a shot that would have still been good enough for social media if only they hadn't missed focus or if only they had used more iso. To me, stabilization seems like it would have been worthwhile and neither one has it, and the iso of the d850 seems like it should already be excessive, but idk. Maybe they also wanted a bigger battery or something? maybe the d5 was on an easier to reach shelf? lol

You're thinking to IBIS (in body image stabilization), which is stabilization done at the sensor level, but there is also the image stabilization done at the lens level, which is more common and (obviously) dependent on the lens you're actually using.

Some camera + lenses combinations have only the former, some only the latter, some have both of them, some have no stabilization at all.

In short, before concluding they have no stabilization you need to know what kind of lenses they're using.

 

[Hispalensis]

Such a potato quality video the moon literally looks like a (off-colour) potato

As the article points out, the laser system has some glaring limitations (I'll see myself out).