Artemis 2 launch - humans return to the Moon after 54 years

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  • #31
Ken Fabian said:
You sure the sun is behind the Earth in this pic?
Yes.

Ken Fabian said:
Remarkable colour photography of night-side
That's because that version of the photo was put through an enhancement algorithm to brighten the night side. Here's what it looked like before that was done:

https://www.nasa.gov/image-detail/amf-art002e000193/

Ken Fabian said:
More usually we would be seeing city lights.
You can see them in the image I linked to above.
 
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  • #32
@PeterDonis - Colour me surprised; I was thinking it might be a composite image - the thin crescent and some glow further out indicating light from behind. I didn't realise night time pictures could be enhanced like that.
 
  • #33
Ken Fabian said:
I didn't realise night time pictures could be enhanced like that.
I suspect the enhancement algorithm made use of outside knowledge about what Earth looks like from space--for example, what clouds look like, what Africa looks like, etc--to help in making the enhanced image look realistic, even if not all of that information was in the original image.
 
  • #34
PeterDonis said:
I suspect the enhancement algorithm made use of outside knowledge about what Earth looks like from space--for example, what clouds look like, what Africa looks like, etc--to help in making the enhanced image look realistic, even if not all of that information was in the original image.
Plenty of grist for the conspiracy mill!
 
  • #35
Have humans ever landed on the Moon?
 
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  • #36
So... like a composite image but not?
 
  • #37
Ken Fabian said:
So... like a composite image but not?
It's a spectacular image, but it's essentially fake. It's not what the crew saw. This raises the question of what is allowable as enhancement or alteration before you have to declare something as "synthetic".
 
  • #38
jurica_c said:
Have humans ever landed on the Moon?
Well I met Buzz Aldrin a few times when I worked at NASA Ames. He definitely appeared human. Not as sure about Neil Armstrong <joke>. He might be super-human.
 
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  • #39
PeroK said:
It's a spectacular image, but it's essentially fake. It's not what the crew saw. This raises the question of what is allowable as enhancement or alteration before you have to declare something as "synthetic".
The human eye adapts well to darkness, although it doesn't see colour well at low light intensity. The earth was lit by full moonlight. If I just save the darker image and "auto-adjust" colour I get quite a similar result, although the available copy of the darker image is lower resolution, so I don't get all the detail.
 
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  • #40
PeroK said:
It's a spectacular image, but it's essentially fake. It's not what the crew saw. This raises the question of what is allowable as enhancement or alteration before you have to declare something as "synthetic".
Nah, if that were true it would mean basically all astrophotos are "fake". They are brightened to the limit of available data. They might have 65,000 levels of brightness (16bit) and only use the bottom few hundred for most. Plus the dynamic range is huge. Solar eclipse photos might be half a dozen different exposures in a composite.

Though if you were led to believe "this is what they saw" that would be misleading.
 
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  • #41
PeroK said:
Plenty of grist for the conspiracy mill!
jurica_c said:
Have humans ever landed on the Moon?
Just a friendly reminder that PF is a science forum and conspiracy theory nonsense does not belong here. Enough said (hopefully).
 
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  • #42
The name Orion had me confused for a second until I looked it up. I was 97% sure we weren't talking about the old type of Orion but in these days it's hard to know anything for sure. Exciting. A lot of stuff is going on right now...

EDIT: Also, looking at the funding as according to Wiki, it doesn't even look that expensive. Relatively I better qualify it with. I'm guessing the dream is to bring boosting material into orbit cheaper.
 
  • #43
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  • #44
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  • #45
sbrothy said:
Heh, "lunacy". :woot:
I call it a Moondoggle.
 
  • #46
Greg Bernhardt said:
Still unclear to me. I get the moon base, but what specifically is this mission's goal? Simply a starting point to prove we can fly around it again?
Artemis I was an unmanned test flight to test various systems and regain experience. Artemis II is the first manned flight in 54 years. It tests the same systems, but now also crew/life support systems. The idea would be to test all the systems to root out any issues/problems and fix before committing to a lunar landing.

It's a similar process with nuclear reactors and plants in which testing (i.e., pre-startup testing, e.g., hydrostatic testing, control systems testing) is performed well before initial criticality. One performs 'cold' and 'hot' testing. After criticality is achieved, power ascension is performed in steps (with holds) to ensure the system behaves as expected (based on sophisticated simulations; power (flux) distribution mapping is performed; control systems are tested). It can takes days/weeks of testing before full power is achieved.

One can also consider testing of new aircraft or marine systems.

Searching Google with "shakedown cruise", Google AI returns:
A shakedown cruise is a final, intensive testing phase for a new or recently repaired ship, submarine, or spacecraft before it enters regular service. It serves as a stress test to evaluate systems, allow the crew to familiarize themselves with the vessel, and fix issues at minimal cost.

NBC News interview with the Artemis II crew
https://www.nbcnews.com/science/spa...interview-space-moon-far-side-nasa-rcna266564

Noticeable is the delay in the conversation between the crew and terrestrial interviewer.
 
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  • #47
Some more media:

FULL LAUNCH: Artemis II is first mission to the moon in 53 years (Fox 13 Seattle)
Video Info said:
NASA’s Artemis II mission lifted off at 6:35 p.m. EDT from Kennedy Space Center’s Launch Complex 39B, sending four astronauts aboard the Space Launch System rocket and Orion spacecraft on a journey around the Moon, officials said.


Artemis 2 crew goes live with Earth on their way to the Moon (VideoFromSpace)
Video Info said:
Artemis 2 commander Reid Wiseman, pilot Victor Glover and mission specialists Christina Koch and Jeremy Hansen talk to ABC and Fox news shortly after their Trans-Lunar Injection burn that set them on a course for the moon.
 
  • #48
PeterDonis said:
Similar to the goal of Apollo 8, as compared to Apollo 11.

(And to date myself, I watched Apollo 11 on TV as a preschooler--a small black and white TV. I still remember seeing how the astronauts hopped around on the Moon.)
ditto from Nairobi, Kenya!
 
  • #49
Wow, what a photo!

3088.webp

Quote: "Christina Koch peers out of one of the Orion spacecraft’s cabin windows at Earth, as the crew travels towards the moon. Photograph: AP"

Source: Artemis II astronauts expected to reach far side of moon on Monday
(The Guardian)
 
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  • #50
A bunch of nice photos here:

Nasa’s Orion spaceship four days into Artemis II mission: in pictures (The Guardian)
https://www.theguardian.com/artandd...rion-spaceship-artemis-ii-mission-in-pictures

Examples:

4000.webp

"The exterior of the spacecraft
Photograph: AP"


3088.webp

"Commander Reid Wiseman looks at the Earth from a window onboard.
Photograph: AP"


4800.webp

"A view of Earth taken by Wiseman from one of the spacecraft’s four windows, after completing the translunar injection burn
Photograph: AP"
 
  • #51
80,000 km to go. The closest approach is 23.5 hours away. Tomorrow's schedule is basically Moon observations the whole day. Besides using cameras, NASA also highlights the power of human eyes and their connected brains - finding things that look unusual, detecting differences in colors or patterns that might be less obvious from a picture, and so on. The crew will be in direct contact with scientists on Earth to decide what to focus on during observations.

Edit: Orion did a trajectory correction maneuver (the first one, the schedule had space for three but the first two were skipped). It now entered the Moon's sphere of influence, and the Moon already appears larger than Earth.
 
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  • #52
russ_watters said:
Nah, if that were true it would mean basically all astrophotos are "fake". They are brightened to the limit of available data. They might have 65,000 levels of brightness (16bit) and only use the bottom few hundred for most. Plus the dynamic range is huge. Solar eclipse photos might be half a dozen different exposures in a composite.

Though if you were led to believe "this is what they saw" that would be misleading.
I often wondered if there exists any vantage point where a Hubble image of a distant object for example, could be seen similarly by the human eye? For example this…
IMG_5417.webp
 
  • #53
bob012345 said:
I often wondered if there exists any vantage point where a Hubble image of a distant object for example, could be seen similarly by the human eye? For example this…View attachment 370730
That's getting a bit off topic, but from some quick Googling, that image is probably of the order of 5 light years high, and the version of the image you've chosen is about 620 pixels high. The angular resolution of the human eye is about 0.0003 radians, so if you for example wanted that to correspond to a pixel, you'd need to be ((5/620)/0.0003) light years away from it to get that view, which I make about 27 light years, from which it would subtend about 10 degrees. That might create a slightly different view because of being close enough for 3D detail to be modified a little. But as it's over 6500 light years away, it's not clear how you would get a human eye anywhere near it.

From what I've read, the Artemis II crew are making a very wide orbit round the moon, with the closest point being about 4070 miles from the moon's surface, and the moon's diameter is about 2159 miles, so I make it that the angle similarly subtended by the moon is less than 25 degrees. That is, the radius of the moon is (2159/2) miles and distance from the centre of the moon is (4070+(2159/2)) miles, so the angle both ways from the centre line to the line of sight touching the surface is 2*arcsin((2159/2)/(4070+(2159/2)), which is just over 24 degrees, or slightly more than a hand span at arm's length.

Edit: CNN describes their view of the moon as about the size of a basketball at arm's length, which matches my calculation but may be easier to visualise.
 
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  • #54
For the original question:

The Short Answer: No, there is no natural vantage point where Hubble images would look like what the human eye sees directly.

Why Not?

1. Wavelength Mismatch: Human Vision: ~400-700nm (visible light), Hubble Primary: UV (115-300nm), Near-IR (800-2500nm)

Most iconic Hubble images capture data outside human visual range:

- Pillars of Creation: Sulphur/hydrogen alpha (red) + oxygen (blue)
- Cosmic Cliffs: Hydrogen alpha + sulfur
- Galaxies: Combined UV, visible, and infrared

2. Exposure Integration: Hubble: Integrates light over minutes to hours; Human Eye: Integrates over ~1/30th of a second

A human would never see the faint structures Hubble captures - they're simply too dim.

3. Dynamic Range Limitation: Hubble: Can capture 25+ magnitudes of brightness difference, Human Eye: Limited to ~6-8 magnitudes in a single view

The Real Insight.

The question reveals a deeper truth: Hubble images are translations, not representations.

They translate:

- Non-visible wavelengths → Visible colours we can understand
- Faint structures → Bright enough to see
- Multiple exposures → Single integrated view
- Scientific data → Aesthetically meaningful images

This is data visualisation, not "what it would look like."
 
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  • #55
PeroK said:
It's a spectacular image, but it's essentially fake. It's not what the crew saw. This raises the question of what is allowable as enhancement or alteration before you have to declare something as "synthetic".
That encompasses the entirety of astronomy imagery. :smile:

In fact, it opens a whole can of worms as to what is "real", since virtually nothing outside our thin atmosphere is something the human eye evolved to see. Pretty much all space images (including all pics of the Moon, the Sun the pandets and nebulae) are dependent on arbitrary pre- and post-imaging settings and processing.
 
  • #56
TheOrionNebula said:
This is data visualisation, not "what it would look like."
Thanks - I knew that the colours were completely artificial and Hubble photos include wavelengths outside the visible spectrum but I had assumed that some similar shape would be visible. (One can for example see the Andromeda galaxy unaided on a dark clear night, which is a lot further away). I thought that although images were very faint, most of that would simply be due to distance, so in the "pillars of creation" case it might be possible to see at least the outline of something similar from only a few light years away. But I don't have the numbers to check that, and I have no problem with assuming you're right about the orders of magnitude.
 
  • #57
The area brightness of an object does not depend on distance. It doesn't depend on the magnification either.
The Pillars of Creation are too dim for the naked eye - at every distance, and even if you look through a telescope. The popular image is heavily edited, too. Here is an original image (one of many) and a visualization of the cleaning and merging process.

The lunar observation day has begun. Live coverage
15,000 km away from the Moon, it'll get larger quickly now. The closest approach is 4 hours away. The crew now holds the records for the largest distance from Earth, breaking the record set by Apollo 13.

Alive people who have been to the Moon, with those who walked on the surface as subset:
1775504433810.webp


The four people who walked on the Moon and are still alive are 90, 90, 93 and 96 now.
 
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