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Artemis II crew take “spectacular” image of Earth

bbc.com

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Re: Artemis II crew take “spectacular” image of Earth

#211

Post by pdonis »

divbzero wrote: post #117
layer8 wrote: post #83

Earlier quoted context omitted.

Before Lightroom it might have looked closer to this: https://images-assets.nasa.gov/image/art002e000193/art002e00...

The photograph appears to show nightime on Earth with just a sliver of daytime. Beyond cities in Iberia and along the coast of Africa, most of what we can see would be reflected light from the Moon? We are just past full moon on April 1.

> Beyond cities in Iberia and along the coast of Africa, most of what we can see would be reflected light from the Moon?

Yes, exactly.

Re: Artemis II crew take “spectacular” image of Earth

#212

Post by pdonis »

hparadiz wrote: post #125
divbzero wrote: post #117

Earlier quoted context omitted.

The photograph appears to show nightime on Earth with just a sliver of daytime. Beyond cities in Iberia and along the coast of Africa, most of what we can see would be reflected light from the Moon? We are just past full moon on April 1.

1/4 exposure time so 250 ms of light. the light is coming from all the light sources in the universe, plus the moon, plus the sun's rays refracting through the atmosphere which happens even at night. The natural blue light is coming from the oxygen in the atmosphere but it's so overwhelming in that spot that it turns the light pure white. The red/orangish is coming from particulates and the green/red from aurora. My…

> the light is coming from all the light sources in the universe, plus the moon

And all the others are negligible by many orders of magnitude compared to the moon. So it's really just the moon as far as this photo is concerned (except for the small sliver that's still illuminated by sunlight, including refracted sunlight).

Re: Artemis II crew take “spectacular” image of Earth

#213

Post by pdonis »

whycombinetor wrote: post #171

"It is the first time since 1972 that humans have travelled outside of the Earth's orbit." But they're not tho (Earth's gravitational dominance extends 4x the distance to the moon)

> It is the first time since 1972 that humans have travelled outside of the Earth's orbit.

They mean outside of low Earth orbit (which basically means further away than the ISS). The phrasing is not ideal.

> Earth's gravitational dominance extends 4x the distance to the moon

"Earth's gravitational dominance" is not a single thing; it depends on what kind of "dominance" you're talking about.

For example, even though the Moon is usually described as being in orbit about the Earth, its orbit is always concave towards the Sun. In other words, its net gravitational acceleration is always towards the Sun--even when the Earth is on the other side of it from the Sun. So by this criterion it's not in orbit about the Earth, it's in orbit about the Sun, doing a complicated do-si-do with the Earth, also in orbit about the Sun.

I'm not sure what definition of "dominance" you're using that extends the Earth's "dominance" to 4 times the distance of the Moon.

Re: Artemis II crew take “spectacular” image of Earth

#214

Post by getnormality »

CommenterPerson wrote: post #208

Why didn't NASA or the news agencies rotate the image so North is up? and slightly to the right. That would make Africa instantly recognizable as that's how maps are imprinted in our brains. There is no "up" in space, so that wouldn't be editing the image I feel. The camera just happened to be oriented "upside down".

I was thinking the same thing, but then I decided to embrace the frustration of the image. It's reminding us that the pictures we have in our heads are kind of fragile. They don't prepare us for a live encounter with Earth from some random angle in space.

Re: Artemis II crew take “spectacular” image of Earth

#215

Post by evolve2k »

Comparing the final two images of taken of earth in 1972 and 2026 respectively; does the 2026 (left) image look murkier and less crisp to anyone else?

Surely our camera gear is exponentially better now? Is the reason for the new image being ‘murkier’ due to light, pollution or something else?

Re: Artemis II crew take “spectacular” image of Earth

#216

Post by mccraveiro »

evolve2k wrote: post #215

Comparing the final two images of taken of earth in 1972 and 2026 respectively; does the 2026 (left) image look murkier and less crisp to anyone else? Surely our camera gear is exponentially better now? Is the reason for the new image being ‘murkier’ due to light, pollution or something else?

1972 -> taken during daytime 2026 -> taken during nightime

Re: Artemis II crew take “spectacular” image of Earth

#217

Post by gus_massa »

narmiouh wrote: post #145
porphyra wrote: post #120

Earlier quoted context omitted.

I'd have probably shot it wide open at f/2.8 rather than cranking the ISO up to 51200. Incredibly impressed at the steady hands for a sharp image at 1/4 s shutter speed though! Maybe they just let the camera float in space with the mirror up, triggering it remotely.

I would imagine since they are not circling the earth, that there will be pull of gravity and the camera would start to move relative to the spacecraft. But may not fast enough for a short exposure

Once you are out of the atmosphere and turn off your thrusters, you are on "fee fall" and the gravity on the camera, you and the spaceship produce the same acceleration and they cancel and it looks exactly like "zero gravity". It doesn't matter if you are in orbit around the Earth, going to the Moon.

Re: Artemis II crew take “spectacular” image of Earth

#218

Post by BHSPitMonkey »

sgt wrote: post #59
damnitbuilds wrote: post #3

Anyone find the full res version of this ? Nasa images page is useless. Government work.

I don't understand why media, such as BBC, keep uploading heavily compressed versions of photos that could be beautiful. The original has grain, sure but that's not a problem. The BBC version is horrific. Are they trying to save on bandwidth in 2026?

It's highly reasonable for them to limit image size/quality to whatever looks fine to 98% of their readers. They store and serve an absolute ton of ever-changing content to browsers/apps; The very small (and likely revenue-negative) contingent of highly motivated people can find the originals if the images are especially noteworthy like these.

Re: Artemis II crew take “spectacular” image of Earth

#219

Post by boca_honey »

1zael wrote: post #202

How are people still flat-earthers after stuff like this

This photo could be easily faked. I don't believe the Earth is flat, but I also don't think everybody on the planet should be 100% on one side of a discussion. Even if flat-earthers are kinda dumb, I think it's worse to force everyone into intellectual submission just because you're "right".
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